Click here to go to the tracking map.
UPDATES:
1/5/2018: It's been a year since I've last given an update. My apologies!
SeaCharger spend about six months in the New Zealand Maritime Museum and then was shipped back to my home in Colorado, arriving last November. You can see some pictures of it on the Gallery page. I haven't fully dissected it, but so far I'm happy with how well everything held up. The electrical connectors seem to be in almost perfect shape, the structure is sound, and there are no signs of leaks. As mentioned before, the rudder is gone and the propeller blades were broken off. I haven't had a chance to power up the rudder servo or the motor to see if it they still work (can't access the electronics because I did a really good job of gluing their enclosure shut).
Repairing the boat and sailing it again would require a lot of time and expense. There are many parts of it that were permanently glued on (like the solar panels) or sealed shut (like the electronics enclosure), so replacing those components would be tricky. I think it's probably better to quit while we're ahead. For now, I plan to show the boat at schools or similar groups when the opportunity arises and hope that somebody finds it interesting or, better yet, inspirational.
1/18/2017: OK, here's the story of the rescue!
Since SeaCharger started drifting in November, both my mom and my friend Neil Hutchison in NZ had been attempting to find a boat nearby that might be able to pick it up, at first with no success. For my part, I was willing to let it drift, mainly because I thought the chances of finding someone to pick it up were so slim. But, as mothers do, my mom kept trying, making cold calls to shipping companies and navies asking for help.
She hit the jackpot when she was given the name of James Dawson at Sofrana Unilines in NZ. It turns out that James is about the nicest guy in the world. He told my mom that Sofrana had a ship on its way from the Solomon Islands to NZ and that he would pass along her request for help to the ship's captain. My mom emailed me with this promising news and I began a discussion with James about how this might work. I would tell SeaCharger to start sending position reports more and more frequently as the ship approached. James would relay these position reports to the ship. If the weather wasn't too bad and if it was daytime when the ship got to SeaCharger's position, the ship would attempt to snag SeaCharger, either with a rope or a net or possibly even by launching their rescue boat.
James compared this to finding a needle in a haystack. I actually had no doubt that they could find the boat, as long as it was daytime. After all, we've had boats rendezvous with SeaCharger before, when it was offshore of Hawaii. But I had no idea how they were going to maneuver a ship that big to get anywhere close to SeaCharger once they spotted it. This ship, the Sofrana Tourville, is 143 meters long! That's one and a half football fields, for you sports fans out there. And I'm sure it doesn't exactly stop on a dime. In my mind, I thought the only way they were going to get it was if they were able to launch their rescue boat.
So the time arrived when the Tourville started to approach SeaCharger. I had SeaCharger reporting its position every ten minutes. Fortunately, it was a couple of hours before dark in New Zealand, so there was enough light to make the rescue. I had no direct contact with the Tourville, but I got a message from the captain via James that the weather is a little rough. This worried me a little, but by this time I'd had enough interaction with James to know that the captain and crew would do everything they could to safely snag the boat.
I could tell roughly where the Tourville was by monitoring their position and heading on marrinetraffic.com (updated about every five minutes). I kept comparing their position to SeaCharger's position until, at one point, it appeared that they had actually passed by SeaCharger. "Darn it," I think, they must've either not found it or decided it was too dangerous to launch their rescue boat. Then, when the next position report for the Tourville came in, I noticed that not only had they stopped, but they'd actually turned around! I couldn't believe it. Not many minutes passed before I got a report from SeaCharger showing that it was moving quite a bit faster than before and that it was upside down. It must've been onboard the ship. Somehow they got it!
A few days later James spoke to the captain and got the details of how they picked up SeaCharger. Here's what he said:
"'Very carefully' is the answer to how they picked it up, I was speaking to the Captain about it – they were plotting its track based on the GPS coordinates that you started sending every 10mins, and trying to predict where it would be as it moved with the current as they got closer. They had guys on lookout with binoculars and sighted it when they got within about 2 cables distance (about 370 metres)."
"When they picked it up visually obviously they didn’t want to get too close to run it over so they predicted which way the current was taking it and basically turned the ship so that Seacharger was approaching the ship from the lee side (with the ship shielding SeaCharger from the wind) and basically just let her drift up alongside. The idea I had about them launching their rescue boat was discussed but rejected as they said it was too choppy to do that safely. So they lowered their pilot ladder (the rope ladder that harbour pilots use to board ships to pilot them into port) and lowered a guy down with a safety harness. I asked the Captain if they had to “volunteer” the youngest guy but he said no they were all queuing up to do it. They took it on as a real challenge of navigation and seamanship and problem-solving skills and really seemed to have enjoyed the whole process so it was a win-win for them and for you."
Amazing!
As expected, SeaCharger was covered with all sorts of nasty ocean-dwelling creatures. The crew was kind enough to clean all that off. In addition to the fouling, the boat had other problems: the rudder was gone and the propeller blades were both broken off. No wonder it wasn't making any progress! I was glad to hear that the motor was still spinning, though. In addition to the broken rudder and propeller, the hull had a couple of nasty gouges in it. I prefer to think that a Great White took a bite out of it, but it was probably just driftwood or something.
After stopping in Tauranga, NZ, the Tourville pulled into Auckland, incidentally right down the road from the NZ Maritime Museum, SeaCharger's soon-to-be home (at least for the next six months). James and his coworkers, as well as my friend Neil, graciously shepherded SeaCharger through the customs process so that it could be brought into the country (a task which was probably just as difficult as plucking it out of the water).
I cannot thank James Dawson, Captain Jorge A. Dato-On Jr and the crew of the Tourville enough. What an incredible feat and an amazingly generous group of people! Enjoy the pictures they took below.
1/5/2018: It's been a year since I've last given an update. My apologies!
SeaCharger spend about six months in the New Zealand Maritime Museum and then was shipped back to my home in Colorado, arriving last November. You can see some pictures of it on the Gallery page. I haven't fully dissected it, but so far I'm happy with how well everything held up. The electrical connectors seem to be in almost perfect shape, the structure is sound, and there are no signs of leaks. As mentioned before, the rudder is gone and the propeller blades were broken off. I haven't had a chance to power up the rudder servo or the motor to see if it they still work (can't access the electronics because I did a really good job of gluing their enclosure shut).
Repairing the boat and sailing it again would require a lot of time and expense. There are many parts of it that were permanently glued on (like the solar panels) or sealed shut (like the electronics enclosure), so replacing those components would be tricky. I think it's probably better to quit while we're ahead. For now, I plan to show the boat at schools or similar groups when the opportunity arises and hope that somebody finds it interesting or, better yet, inspirational.
1/18/2017: OK, here's the story of the rescue!
Since SeaCharger started drifting in November, both my mom and my friend Neil Hutchison in NZ had been attempting to find a boat nearby that might be able to pick it up, at first with no success. For my part, I was willing to let it drift, mainly because I thought the chances of finding someone to pick it up were so slim. But, as mothers do, my mom kept trying, making cold calls to shipping companies and navies asking for help.
She hit the jackpot when she was given the name of James Dawson at Sofrana Unilines in NZ. It turns out that James is about the nicest guy in the world. He told my mom that Sofrana had a ship on its way from the Solomon Islands to NZ and that he would pass along her request for help to the ship's captain. My mom emailed me with this promising news and I began a discussion with James about how this might work. I would tell SeaCharger to start sending position reports more and more frequently as the ship approached. James would relay these position reports to the ship. If the weather wasn't too bad and if it was daytime when the ship got to SeaCharger's position, the ship would attempt to snag SeaCharger, either with a rope or a net or possibly even by launching their rescue boat.
James compared this to finding a needle in a haystack. I actually had no doubt that they could find the boat, as long as it was daytime. After all, we've had boats rendezvous with SeaCharger before, when it was offshore of Hawaii. But I had no idea how they were going to maneuver a ship that big to get anywhere close to SeaCharger once they spotted it. This ship, the Sofrana Tourville, is 143 meters long! That's one and a half football fields, for you sports fans out there. And I'm sure it doesn't exactly stop on a dime. In my mind, I thought the only way they were going to get it was if they were able to launch their rescue boat.
So the time arrived when the Tourville started to approach SeaCharger. I had SeaCharger reporting its position every ten minutes. Fortunately, it was a couple of hours before dark in New Zealand, so there was enough light to make the rescue. I had no direct contact with the Tourville, but I got a message from the captain via James that the weather is a little rough. This worried me a little, but by this time I'd had enough interaction with James to know that the captain and crew would do everything they could to safely snag the boat.
I could tell roughly where the Tourville was by monitoring their position and heading on marrinetraffic.com (updated about every five minutes). I kept comparing their position to SeaCharger's position until, at one point, it appeared that they had actually passed by SeaCharger. "Darn it," I think, they must've either not found it or decided it was too dangerous to launch their rescue boat. Then, when the next position report for the Tourville came in, I noticed that not only had they stopped, but they'd actually turned around! I couldn't believe it. Not many minutes passed before I got a report from SeaCharger showing that it was moving quite a bit faster than before and that it was upside down. It must've been onboard the ship. Somehow they got it!
A few days later James spoke to the captain and got the details of how they picked up SeaCharger. Here's what he said:
"'Very carefully' is the answer to how they picked it up, I was speaking to the Captain about it – they were plotting its track based on the GPS coordinates that you started sending every 10mins, and trying to predict where it would be as it moved with the current as they got closer. They had guys on lookout with binoculars and sighted it when they got within about 2 cables distance (about 370 metres)."
"When they picked it up visually obviously they didn’t want to get too close to run it over so they predicted which way the current was taking it and basically turned the ship so that Seacharger was approaching the ship from the lee side (with the ship shielding SeaCharger from the wind) and basically just let her drift up alongside. The idea I had about them launching their rescue boat was discussed but rejected as they said it was too choppy to do that safely. So they lowered their pilot ladder (the rope ladder that harbour pilots use to board ships to pilot them into port) and lowered a guy down with a safety harness. I asked the Captain if they had to “volunteer” the youngest guy but he said no they were all queuing up to do it. They took it on as a real challenge of navigation and seamanship and problem-solving skills and really seemed to have enjoyed the whole process so it was a win-win for them and for you."
Amazing!
As expected, SeaCharger was covered with all sorts of nasty ocean-dwelling creatures. The crew was kind enough to clean all that off. In addition to the fouling, the boat had other problems: the rudder was gone and the propeller blades were both broken off. No wonder it wasn't making any progress! I was glad to hear that the motor was still spinning, though. In addition to the broken rudder and propeller, the hull had a couple of nasty gouges in it. I prefer to think that a Great White took a bite out of it, but it was probably just driftwood or something.
After stopping in Tauranga, NZ, the Tourville pulled into Auckland, incidentally right down the road from the NZ Maritime Museum, SeaCharger's soon-to-be home (at least for the next six months). James and his coworkers, as well as my friend Neil, graciously shepherded SeaCharger through the customs process so that it could be brought into the country (a task which was probably just as difficult as plucking it out of the water).
I cannot thank James Dawson, Captain Jorge A. Dato-On Jr and the crew of the Tourville enough. What an incredible feat and an amazingly generous group of people! Enjoy the pictures they took below.
1/10/2017: Rescued! This evening the captain and crew of the Sofrana Tourville heroically rescued Seacharger and are bringing it to New Zealand! Thank you so much to Sofrana and to my mom for arranging the rescue! More details to follow in a week or two...
12/19/2016: Seacharger has been adrift for one month now. It spent some time going around in circles in an eddy but now seems to have gotten spit out of the eddy. It'll be super interesting to see where it ends up. If you want a general idea of what the currents are doing in that part of the ocean, go to https://earth.nullschool.net/ and click on Earth > Ocean > Currents. If you click on the map, it'll show you the latitude and longitude at that point. Today the boat is at -29.6,177.1. So if you find that point on the map, you'll find that the boat is in a current flowing towards the northwest. Maybe we'll get lucky and it'll loop around to the west and then south and get spit out towards the northern tip of New Zealand. You never know...
A lot of people have asked about chartering a boat to go pick up SeaCharger. It's just too far. Unless anybody out there wants to donate a couple tens of thousands of dollars??? I've also been asked if I can just turn on the thruster when the boat is pointing in the direction I want to go and turning it off when it's not. I have tried that a couple of times and haven't really had any success. In fact, the last time I tried it, it didn't make the slightest difference. So I'm willing the bet the thruster is dead too. Either way, it would take a huge amount of time and a hefty satellite bill to really make that work even if the thruster were still working. Let's just see where the currents take it...
11/19/2016: Well folks, SeaCharger is officially dead. At some point yesterday its rudder stopped working. I tried cycling power to the rudder and then I tried resetting the entire system (which I had never done before, but it actually worked, which was sort of nice to see), but all to no avail. The thruster still appears to be working, so I'll just leave it on and see where the boat goes. It'll at least be fun to see where it ends up. I'm going to have it check in just once a day from now on. Anyway, I guess all good things must come to an end.
SeaCharger racked up over five months in the water and traveled roughly 6500 nautical miles. Not bad. Thank you so much to all of you who have contacted me and shown such interest! This has been an absolutely amazing experience for me!
11/13/2016: First of all, to all of our friends in New Zealand, we're so sorry to hear about the earthquakes! Stay safe. Regarding the boat, it was disappointing this past week that the wind and currents were not as favorable as I thought they were going to be. The boat made great speed, but it was towards Chile, not New Zealand. But now over the past 12 hours or so the boat has been heading southwest again instead of east, so that's good. The boat still navigates just fine in calm water, but when the winds pick up, it's sort of at their mercy.
11/6/2016: We FINALLY got some really good weather: either calm or blowing hard, but in the right direction. And the boat even seems to be in a southward-flowing current right now. I had a little scare today because the boat failed to check in four times in a row. And it was right at a time when it was in the middle of some really blustery weather. So I figured it was a goner, having been blown to bits or something like that. Well, it turned out that I just hadn't paid the satellite bill. So I paid it and now the boat is communicating again
11/1/2016: Nevermind that previous post. We'll try for New Zealand after all. The boat doesn't seem to be getting significantly slower lately and the winds have shifted so that they're not always from the south now. So what the heck, might as well try to make it.
10/24/2016: Well New Zealand, I'm sorry to have let you down, but the boat just isn't making any southward progress. The wind, waves, and currents are all conspiring to push the boat northward. I imagine that the boat is carrying a large load of barnacles by now which makes it impossible for it to make any headway into these conditions. So for the past two days the boat has been commanded to head straight west to see if it can make it to Norfolk Island or even New Caledonia. So far the weather has continued to push it north (even though the nose is trying to point west), making the actual course towards the northwest. I'm going to just see what happens over the next few days, whether it keeps going towards the north or not, and then decide later whether to head for New Caledonia or Norfolk Island. I guess New Zealand is still a possibility if at some point conditions become favorable for it to turn south. But either way, heading west gives the boat some options. And the boat is going noticeably faster when heading west (roughly .7 m/s average compared to about -0.3 m/s when trying to go south).
On the bright side, the boat seems to be doing very well electrically. Yesterday its batteries got fully charged WITHOUT me having to turn off the motor, which hasn't happened since it's California to Hawaii voyage. It's nice to have longer days!
Oh by the way, if you've looked at the tracking map in the last day or two you'll have noticed that the boat's not reporting anymore. Actually it's just an issue with the tracking map. The boat is still there. I'm sure my buddy Ryan will get the tracking map up and running again soon.
10/20/2016: About 630 miles to New Zealand. Just plodding along. At this rate it's going to take another month to get there, which is fine by me. It's just a question of whether it gets even slower or decides to die. At least the days are getting longer!
10/15/2016: About 725 miles to New Zealand. Really poor progress lately. In fact, I think it actually went backwards today. I know the motor is still turning and the rudder is still working, and I know that it's in a strong current right now pushing it to the east. In it's younger days it probably would've handled these conditions okay, but it must be covered in barnacles and/or just weak in general. Let's hope for some really helpful weather...
10/10/2016: 3867 miles so far since Hawaii. About 860 miles to New Zealand. Sure could use a little more sun! The boat was stuck under thick clouds for the past day or two. Fortunately there's a strong, favorable current right now, so in spite of the motor being off for much of the time, the boat is still making good progress.
10/4/2016: 3594 miles so far since re-launching on July 27. 110 days total at sea. About 1100 miles to New Zealand. The boat has been really slow lately (averaging only 35 miles per day over the past few days). I've given up trying to figure out why. Currents? Waves? Barnacles? Who knows? It's still going, and that's all that matters.
9/23/2016: 3199 miles so far since re-launching on July 27. 58 days at sea since the re-launch, 99 days total. Maybe another four weeks until New Zealand. This boat has got to be tired by now, don't you think? Just got to hold on a little longer. Tonight it's going to transition from tracking a waypoint in the western hemisphere to tracking a waypoint in the eastern hemisphere. That's because New Zealand is just west of the antimeridian. I didn't make that word up; I found it on wikipedia. It's the opposite of the prime meridian, or in other words, it's the line of 180 degrees longitude. Anyway, let's hope the math works out right and the software doesn't hang up. It did fine going from the northern to southern hemispheres so I'm sure it'll be fine going from western to eastern.
Pretty soon I'm also going to have to adjust the boat's compass to account for the local magnetic declination. That's the the difference between true north and magnetic north. In Hawaii, the magnetic declination is something like 12 degrees. The area surrounding New Zealand is really messed-up magnetically because it's so close to the magnetic south pole. At Auckland (in northern New Zealand), the declination is about 19 degrees. Down at the south end, it's about 26 degrees. Not really a big deal for Seacharger. All it means is that it'll end up tracking a little to the left or right of its intended path if I don't make the adjustment. But it's nice to have it "right" anyway. Now if the boat ended up close to the magnetic south pole, then it'd be in trouble because it would have no way of knowing which way it's pointing. Currently, the magnetic south pole is in fact on water, not on land (just in case you were wondering how a boat could ever get there). Did you know that at some point in the future the earth's magnetic field will flip and north will become south? Crazy stuff.
9/14/2016: 2832 miles so far since re-launching on July 27. Today I had a bit of a scare when the boat failed to check in. It hadn't failed to check in for a long, long time, so naturally I got worried. Then I started to figure out how long it's been since it was relaunched from Hawaii and realized that it has been over 49 days. If any of you out there just exclaimed "Aha!" after reading that last sentence, congratulations, you're truly a geek. For the rest of you, 49 days is special because if you convert it to milliseconds, it's about 2^32. In an Arduino, the internal timer stores the time, in milliseconds, as a 32-bit number. So after 49 days, the Arduino's internal timer has to reset, which can have unintended consequences. Fortunately there are ways to handle this so that the code doesn't crash or hang up, but I've never had the chance to test this before. So I was quite relieved when Seacharger did in fact check in again, albeit two hours later than expected.
When Seacharger checked in again after the timer reset, I triumphantly told my wife that it had just passed a significant milestone. "Oh yeah, what milestone is that?" she asked. So I started to explain about 49 days and 32-bit numbers and such. Now she's a history major, so her interest in this stuff is only based on her love for me, not any passion for the material itself. So after reviewing binary numbers and what-not, with her alternately grinning and grimacing, and me finally concluding that the maximum value of a 32-bit number is 2^32 and that 2^32 milliseconds is about 49 days and that therefore the Arduino had to reset its internal timer today, she said to me, "Oh, so this is basically the Y2K of Seacharger?" Perfect. Couldn't have said it better myself.
9/10/2016: 2595 miles so far since re-launching on July 27. Still just chuggin' along. There's a giant band of clouds south of where the boat is right now. I sure hope they go away over the next couple of days. Overall, the New Zealand neighborhood has been very cloudy for as long as I've been paying attention. Is that a winter-time thing? Or is always dreary down there? I knew we should've done a sailboat instead.
9/5/2016: 2320 miles so far since re-launching on July 27. Pretty much halfway to New Zealand! Hard to believe it's still alive. Darn it, if I had sent it back to California, I'd almost have it back by now. Oh well. Still a good 2000 miles to go before New Zealand. Getting pretty close to Samoa, though. Any Samoans out there following this? In my last report I said I was going to command the boat to go on a straight line instead of just commanding a heading. Well, I did that for a half of a day, but the current was still strong enough that the boat ended up spending most of its energy just trying to fight the current. So I went back to commanding a heading. Right now the heading command is 160 (20 degrees to the east of south) but it's still moving a little westward. I'm going to let it keep getting pushed west, even though there are more islands over there. I'll just have to keep a close eye on it.
8/30/2016: 1930 miles so far since re-launching on July 27. Yesterday the boat crossed the equator! You may have noticed the tracking map looks different now. Now it has arrows showing the boat's heading (thank you Ryan VanSickle). So if you look at the last several days of data, you'll see that the boat has been pointed directly south, even though it's been moving southwest. That's a result of the very strong current in this area. In the interest of making as much progress as possible, it was better to allow the current to push the boat around and just keep the boat's nose pointed south instead of trying to stay on a straight line. However, it's beginning to get close to some islands to the west of it's current position, so this morning I commanded it back to a straight line. Hopefully it's past the worst of the currents and it'll be able to make good progress on the straight line. Electrically, the boat seems to be holding steady. It's still struggling to charge up all the way during the day so I still have it throttled down, but at least it's not getting worse.
8/25/2016: 1500 miles so far since re-launching on July 27. 52.5 miles per day average, compared to 57 miles per day average on the California-Hawaii trip. Almost every morning the boat runs out of juice. I still can't figure out if it's something wrong with the boat or just cloudy weather or a combination of both. I do know that, a few days ago, it had a good day where the battery got charged up fully during the day and the motor ran all the way through the night. But since then it hasn't able to charge the battery all the way during the day. Whatever; it's still running. In a few days it should be crossing the equator!
8/11/2016: 838 miles so far since re-launching on July 27. Everything's going smoothly so far!
8/5/2016: I've been taking a break from obsessing about SeaCharger, which means I've been taking a break from writing updates. But SeaCharger is still alive and well, making good time. After launch, it went offshore of Hawaii for a few days to do some performance testing in the rather choppy water offshore. Now it's headed towards New Zealand. I'm hoping it at least makes it another 1000 miles.
7/27/2016: After recovering the boat, it sat in our vacation rental in Hawaii for a few days while we continued to vacation. Then once I had a few spare hours, I scraped off the barnacles, touched up a few areas with the anti-biofouling paint, tried to fix a corroded solar panel wire, and reprogrammed it with a couple of software changes. Then this morning we took it to lovely Hapuna Beach and put it back in the water. It was nice to be able to launch it in warm water with only tiny waves and without the pressure of thinking that it has to perform. However far it goes now will just be a bonus!
7/22/2016: All done! Seacharger arrived at Mahukona Harbor this evening. There were a few hiccups with the boat not wanting to let me take over with the R/C transmitter and manually steer it in, so those of you watching the tracking map will have seen it going back and forth a bit. In the end, I just aimed it right into the harbor and my wife jumped in with flippers and a snorkel to save it from the rocks and steer it the last few yards to where my brother and I pulled it out of the water. The boat was very clean! Just a few little barnacles. I'll post some pictures and stats over the next couple of days.
7/21/2016: 67.7 miles today, 22 miles to go to next waypoint. Looking good! Just one more day! And not a moment too soon, as tropical storm Darby is going to hit Hawaii the day after tomorrow. It looks like the boat will either arrive at Mahukona Harbor at about 6pm local time tomorrow or Kawaihae at 10 pm local time. Sunset is around 7pm. So I think I'll shoot for Mahukona. We'll recover the boat and then enjoy the sunset.
Our adventures in paradise today included walking to the bottom of Waipio Valley, which is quite the steep hike. A lot steeper and longer than we had anticipated. Oh, and it was hot and muggy and rainy. In the minds of some of our kids, hiking up and down a long, steep hill in these conditions is just about the greatest evil the world has to offer. Fortunately, at the bottom of the valley we met with the greatest good that the world has to offer (at least in the mind of our teenage girl): horses. Wild ones that come up to you and want to be petted. No, seriously. It was better than anything I could have made up. Disaster averted.
7/20/2016: 60.0 miles today, 89 miles to go. Good day today. Remember it's 89 miles to go to the next waypoint, but then another 60 or so till it actually reaches land. The battery got a full charge today for the first time in about 5 days due to the clouds being fairly minimal. I guess that also explains why two of my kids returned from snorkeling today with sunburnt backs. I'm sure they still think it was worth it. We saw a little shark (which only freaked out my oldest, the others were fine with it) and an amazing octopus that changed both color and texture instantaneously to match the coral it was sitting on. Having the technology to send a little boat across the ocean and communicate with it all along the way via satellite is definitely cool, but it sort of pales in comparison to watching an animal virtually disappear right before your eyes.
7/19/2016: 52.4 miles today, 149 miles to go. Today I flew to Hawaii to hopefully pick up the boat. Almost there! On the flight over, I could see why the battery hasn't been charging very well lately. Too many darn clouds. So it's still running at low throttle. I just hope that it doesn't get stuck in a strong current in the early morning hours when it's totally out of juice. Battery management is going to be important from here on.
7/18/2016: 49.6 miles today, 202 miles to go. A good enough day, but obviously the favorable current disappeared. Still seeing lots of clouds, so the battery still isn't fully charging, so it's been throttled down all day. I've really got to make sure that when it approaches Hawaii, it's got enough energy in the battery that it doesn't cut the motor off, as that could cause it to end up drifting onto the rocks.
7/17/2016: 81.8 miles today, 250 miles to go. Another great day, in spite of running out of juice in the early morning. Again, I'm going to blame it on clouds from Celia. We'll see if things improve tomorrow in terms of charging the battery. By the way, the number I'm giving for "miles to go" is actually not to the actual shore of Hawaii, but rather to the next waypoint, which is about 60 miles offshore. So the point is, you've gotta add 60 miles to that. So it's really 310 miles to go.
7/16/2016: 81.1 miles today, 326 miles to go. That's a whopping 3.4 miles per hour or 2.9 knots, folks! Only in the obscure, forgotten world of small unmanned solar-powered boats would that be considered fast, but whatever. I'll take what I can get. Actually, it would be going a little bit faster if I didn't have the motor throttled down a little. The battery hasn't been fully charged for a few days. I figure it's clouds from post-tropical storm Celia (I think that's the technical term for a hurricane in retirement). Maybe there's gunk on the solar panels. Who knows. Anyway, even with the motor throttled down a bit, we should have a good day tomorrow, too, if the current models are right.
7/15/2016: 71.6 miles today, 407 miles to go. Ahhh... MUCH better! Must be out of the bad current and into the good current. You know, I can't tell you how many times I've thought that the boat had some kind of terminal illness, whether it be the solar panels not charging the battery, the motor not running, the satellite modem not reporting, or the boat being snagged by some trash. But every time I think it's all over, the thing recovers and I realize I was just being paranoid.
I changed the report rate from once per two hours to once per hour, so if you look at the tracking map, that's why the upside-down teardrops are closer together. I figured it'll only cost another 40 bucks or so over the next week to get hourly updates, and I'd much rather know if something is wrong sooner. There's that paranoia again.
7/14/2016: 42.7 miles today, 479 miles to go. Too bad some of those 42.7 miles were actually in the wrong direction (motor stopped again). The boat's starting to make me nervous.
7/13/2016: 45.8 miles today, 517 miles to go. Well that was a pretty slow day. I'm going to blame it on currents again. That plus the fact that the motor shut off again for a few hours and I had to restart it. If the boat actually arrives in Hawaii I'm going to program it to restart the thruster automatically whenever it sees the speed drop below a certain amount. That would definitely help me sleep better. Literally.
7/12/2016: 60.6 miles today, 562 miles to go. Pretty decent day. THREE QUARTERS OF THE WAY THERE!!!
7/11/2016: 67.2 miles today, 622 miles to go. The battery saw its lowest voltage yet this morning, so low that it completely turned the motor off for an hour or so (intentionally, to save power). I'm assuming it's due to cloudiness yesterday not allowing the battery to fully charge. So if it's cloudy and the solar panels aren't producing much power, how can the boat still make such good time? It's because the power required to run the boat is proportional to the speed of the boat to the third power. So to go just 10% faster, you need 33% more power. Or to look at it in a more positive light, if you have only half the available power, the boat will still go 80% of full speed. So even though the solar panels may have been producing much less power than normal, it actually doesn't affect the boat speed that much. This same principle applies to cars, and it's a good reason not to speed on the highway: in addition to being dangerous, you have to burn a lot more gas to go just a little bit faster.
7/10/2016: 57.7 miles today, 690 miles to go. OK, much better today. The motor was a little weird this morning, not putting out much power. I think that once it throttles down, it sometimes has trouble throttling back up. Why did it throttle down in the first place? Well, if the battery voltage drops below a certain level, it'll throttle down to save power. For the past two weeks it's been able to make it through the night without the voltage dropping that low, but last night the battery voltage got lower than normal. Why? I think there might have been some cloudy weather yesterday causing it to not be able to recharge fully. And there might be some more cloudiness today. Anyway, I had to do another motor restart this morning and that seemed to get it going again.
Speaking of weather... there is one person who follows SeaCharger's progress even closer than I do, my mom, and she informed me today that there's a possible HURRICANE on its way to Hawaii!!! So that has me a little nervous. We'll have to monitor that. Not like there's much I can do to make the boat avoid the hurricane. I do pray a lot, though, and if the Lord has seen fit to bring the boat this far, then why not bring it through a hurricane?
7/9/2016: 46.8 miles today, 747 miles to go. Another slow day but the speed was picking up towards the end of the day, so I'm hoping for a better tomorrow.
7/8/2016: 49.5 miles today, 793 miles to go. Pretty dismal day. I think the boat's stuck in a current still. I tried some evasive maneuvers to try to get out of the current but probably should've just left it alone. You'll notice that even though it went 49.5 miles, it's only 43 miles closer than it was yesterday. That's because of all the zigging and zagging.
7/7/2016: 57.0 miles today, 836 miles to go. Right now it seems to be fighting a fairly strong current, so it's going pretty slow. Check out this website: https://earth.nullschool.net/ . It's about the coolest thing in the world. You can see winds, waves, currents, and other stuff, almost anywhere on earth.
7/6/2016: 56.7 miles today, 893 miles to go. The motor shut off again this morning, so we lost some ground there.
7/5/2016: 68.4 miles today, 949 miles to go.
7/4/2016: 68.6 miles today, 1018 miles to go. Average speed over the entire trip so far: 57 miles per day.
7/3/2016: 53.9 miles today, 1087 miles to go. A little slower today.
7/2/2016: 66.4 miles today, 1141 miles to go. HALFWAY THERE!
7/1/2016: 73.3 miles today, 1207 miles to go. Woo hoo! Must've caught a nice bit of current.
6/30/2016: 69.6 miles today, 1280 miles to go. Just keep swimming. Just keep swimming.
6/29/2016: 64.6 miles today, 1350 miles to go. 1,000 miles down!
6/28/2016: 66.1 miles today, 1414 miles to go. Just truckin' along.
6/27/2016: 58.7 miles today, 1481 miles to go. Another good day.
6/26/2016: 59.7 miles today, 1539 miles to go. A THIRD OF THE WAY THERE! The boat was really moving today, but unfortunately the motor shut off for a few hours until I was able to restart it again. It had done that once before. Don't know why, but as long as it does it infrequently, it's fine by me. Anyway, in spite of the motor shutting off, it still had a good day.
6/25/2016: 59.3 miles today, 1598 miles to go. Another good day.
6/24/2016: 57.9 miles today, 1658 miles to go. Not bad mileage, especially considering that I left the throttle at 90% for most of the day. Normally I bring the throttle down to 90% at night and then raise it back up to 100% in the morning. This is because there isn't quite enough battery capacity to go all night at full throttle. Last night I brought the throttle down to 90% but then I went camping with my kids in a place without phone service, so I had no way to bring the throttle back to 100% this morning. But on the bright side, my small kids did a fantastic job on our 8-mile hike with no snacks and minimal water. And we counted 91 banana slugs on the hike!
6/23/2016: 54.1 miles today, 1716 miles to go. Certainly a little slower today, but still going strong.
6/22/2016: 67.6 miles today, 1770 miles to go. A QUARTER OF THE WAY THERE!!! And the most miles covered in a day so far! I also saw the highest reported speed so far (1.47 m/s, or 3.29 mph). What makes it go faster some days? I think it's mostly the wind. I noticed early in testing that a crosswind causes the boat to lean pretty hard to one side, which I assumed would slow it down (especially if it leans far enough for the side of the solar panel deck to get dragged through the water). But from what I've seen so far during its journey to Hawaii, it likes to have a crosswind. I believe the boat is actually sailing. Below is a graph of the boat's speed vs. the absolute value of its roll angle. Not totally conclusive, but there seems to be trend showing that speed increases as the roll angle (which is caused by a crosswind) increases.
Some of you have been asking for more telemetry. So the next picture shows the voltage and current history for the journey so far. The current shown is the current being produced by the solar panels. Some of that current goes to charging the battery, some of it goes to running the motor, and a little bit of it goes to running the electronics and the rudder servo. Unfortunately I don't have individual current sensors for those different loads. But you can sort of deduce what the current going into the motor by looking for times when the battery is fully charged (which is when you see the battery voltage above 20 volts). At these times, there's no current going into the battery, so the only things drawing current are the electronics, the rudder servo, and the motor. The motor probably accounts for 95% of that. So you can tell that the motor draws about 1 amp * 20 volts = 20 watts at full throttle. Actually, I don't really trust my current sensor, so I would put a healthy uncertainty on that number.
12/19/2016: Seacharger has been adrift for one month now. It spent some time going around in circles in an eddy but now seems to have gotten spit out of the eddy. It'll be super interesting to see where it ends up. If you want a general idea of what the currents are doing in that part of the ocean, go to https://earth.nullschool.net/ and click on Earth > Ocean > Currents. If you click on the map, it'll show you the latitude and longitude at that point. Today the boat is at -29.6,177.1. So if you find that point on the map, you'll find that the boat is in a current flowing towards the northwest. Maybe we'll get lucky and it'll loop around to the west and then south and get spit out towards the northern tip of New Zealand. You never know...
A lot of people have asked about chartering a boat to go pick up SeaCharger. It's just too far. Unless anybody out there wants to donate a couple tens of thousands of dollars??? I've also been asked if I can just turn on the thruster when the boat is pointing in the direction I want to go and turning it off when it's not. I have tried that a couple of times and haven't really had any success. In fact, the last time I tried it, it didn't make the slightest difference. So I'm willing the bet the thruster is dead too. Either way, it would take a huge amount of time and a hefty satellite bill to really make that work even if the thruster were still working. Let's just see where the currents take it...
11/19/2016: Well folks, SeaCharger is officially dead. At some point yesterday its rudder stopped working. I tried cycling power to the rudder and then I tried resetting the entire system (which I had never done before, but it actually worked, which was sort of nice to see), but all to no avail. The thruster still appears to be working, so I'll just leave it on and see where the boat goes. It'll at least be fun to see where it ends up. I'm going to have it check in just once a day from now on. Anyway, I guess all good things must come to an end.
SeaCharger racked up over five months in the water and traveled roughly 6500 nautical miles. Not bad. Thank you so much to all of you who have contacted me and shown such interest! This has been an absolutely amazing experience for me!
11/13/2016: First of all, to all of our friends in New Zealand, we're so sorry to hear about the earthquakes! Stay safe. Regarding the boat, it was disappointing this past week that the wind and currents were not as favorable as I thought they were going to be. The boat made great speed, but it was towards Chile, not New Zealand. But now over the past 12 hours or so the boat has been heading southwest again instead of east, so that's good. The boat still navigates just fine in calm water, but when the winds pick up, it's sort of at their mercy.
11/6/2016: We FINALLY got some really good weather: either calm or blowing hard, but in the right direction. And the boat even seems to be in a southward-flowing current right now. I had a little scare today because the boat failed to check in four times in a row. And it was right at a time when it was in the middle of some really blustery weather. So I figured it was a goner, having been blown to bits or something like that. Well, it turned out that I just hadn't paid the satellite bill. So I paid it and now the boat is communicating again
11/1/2016: Nevermind that previous post. We'll try for New Zealand after all. The boat doesn't seem to be getting significantly slower lately and the winds have shifted so that they're not always from the south now. So what the heck, might as well try to make it.
10/24/2016: Well New Zealand, I'm sorry to have let you down, but the boat just isn't making any southward progress. The wind, waves, and currents are all conspiring to push the boat northward. I imagine that the boat is carrying a large load of barnacles by now which makes it impossible for it to make any headway into these conditions. So for the past two days the boat has been commanded to head straight west to see if it can make it to Norfolk Island or even New Caledonia. So far the weather has continued to push it north (even though the nose is trying to point west), making the actual course towards the northwest. I'm going to just see what happens over the next few days, whether it keeps going towards the north or not, and then decide later whether to head for New Caledonia or Norfolk Island. I guess New Zealand is still a possibility if at some point conditions become favorable for it to turn south. But either way, heading west gives the boat some options. And the boat is going noticeably faster when heading west (roughly .7 m/s average compared to about -0.3 m/s when trying to go south).
On the bright side, the boat seems to be doing very well electrically. Yesterday its batteries got fully charged WITHOUT me having to turn off the motor, which hasn't happened since it's California to Hawaii voyage. It's nice to have longer days!
Oh by the way, if you've looked at the tracking map in the last day or two you'll have noticed that the boat's not reporting anymore. Actually it's just an issue with the tracking map. The boat is still there. I'm sure my buddy Ryan will get the tracking map up and running again soon.
10/20/2016: About 630 miles to New Zealand. Just plodding along. At this rate it's going to take another month to get there, which is fine by me. It's just a question of whether it gets even slower or decides to die. At least the days are getting longer!
10/15/2016: About 725 miles to New Zealand. Really poor progress lately. In fact, I think it actually went backwards today. I know the motor is still turning and the rudder is still working, and I know that it's in a strong current right now pushing it to the east. In it's younger days it probably would've handled these conditions okay, but it must be covered in barnacles and/or just weak in general. Let's hope for some really helpful weather...
10/10/2016: 3867 miles so far since Hawaii. About 860 miles to New Zealand. Sure could use a little more sun! The boat was stuck under thick clouds for the past day or two. Fortunately there's a strong, favorable current right now, so in spite of the motor being off for much of the time, the boat is still making good progress.
10/4/2016: 3594 miles so far since re-launching on July 27. 110 days total at sea. About 1100 miles to New Zealand. The boat has been really slow lately (averaging only 35 miles per day over the past few days). I've given up trying to figure out why. Currents? Waves? Barnacles? Who knows? It's still going, and that's all that matters.
9/23/2016: 3199 miles so far since re-launching on July 27. 58 days at sea since the re-launch, 99 days total. Maybe another four weeks until New Zealand. This boat has got to be tired by now, don't you think? Just got to hold on a little longer. Tonight it's going to transition from tracking a waypoint in the western hemisphere to tracking a waypoint in the eastern hemisphere. That's because New Zealand is just west of the antimeridian. I didn't make that word up; I found it on wikipedia. It's the opposite of the prime meridian, or in other words, it's the line of 180 degrees longitude. Anyway, let's hope the math works out right and the software doesn't hang up. It did fine going from the northern to southern hemispheres so I'm sure it'll be fine going from western to eastern.
Pretty soon I'm also going to have to adjust the boat's compass to account for the local magnetic declination. That's the the difference between true north and magnetic north. In Hawaii, the magnetic declination is something like 12 degrees. The area surrounding New Zealand is really messed-up magnetically because it's so close to the magnetic south pole. At Auckland (in northern New Zealand), the declination is about 19 degrees. Down at the south end, it's about 26 degrees. Not really a big deal for Seacharger. All it means is that it'll end up tracking a little to the left or right of its intended path if I don't make the adjustment. But it's nice to have it "right" anyway. Now if the boat ended up close to the magnetic south pole, then it'd be in trouble because it would have no way of knowing which way it's pointing. Currently, the magnetic south pole is in fact on water, not on land (just in case you were wondering how a boat could ever get there). Did you know that at some point in the future the earth's magnetic field will flip and north will become south? Crazy stuff.
9/14/2016: 2832 miles so far since re-launching on July 27. Today I had a bit of a scare when the boat failed to check in. It hadn't failed to check in for a long, long time, so naturally I got worried. Then I started to figure out how long it's been since it was relaunched from Hawaii and realized that it has been over 49 days. If any of you out there just exclaimed "Aha!" after reading that last sentence, congratulations, you're truly a geek. For the rest of you, 49 days is special because if you convert it to milliseconds, it's about 2^32. In an Arduino, the internal timer stores the time, in milliseconds, as a 32-bit number. So after 49 days, the Arduino's internal timer has to reset, which can have unintended consequences. Fortunately there are ways to handle this so that the code doesn't crash or hang up, but I've never had the chance to test this before. So I was quite relieved when Seacharger did in fact check in again, albeit two hours later than expected.
When Seacharger checked in again after the timer reset, I triumphantly told my wife that it had just passed a significant milestone. "Oh yeah, what milestone is that?" she asked. So I started to explain about 49 days and 32-bit numbers and such. Now she's a history major, so her interest in this stuff is only based on her love for me, not any passion for the material itself. So after reviewing binary numbers and what-not, with her alternately grinning and grimacing, and me finally concluding that the maximum value of a 32-bit number is 2^32 and that 2^32 milliseconds is about 49 days and that therefore the Arduino had to reset its internal timer today, she said to me, "Oh, so this is basically the Y2K of Seacharger?" Perfect. Couldn't have said it better myself.
9/10/2016: 2595 miles so far since re-launching on July 27. Still just chuggin' along. There's a giant band of clouds south of where the boat is right now. I sure hope they go away over the next couple of days. Overall, the New Zealand neighborhood has been very cloudy for as long as I've been paying attention. Is that a winter-time thing? Or is always dreary down there? I knew we should've done a sailboat instead.
9/5/2016: 2320 miles so far since re-launching on July 27. Pretty much halfway to New Zealand! Hard to believe it's still alive. Darn it, if I had sent it back to California, I'd almost have it back by now. Oh well. Still a good 2000 miles to go before New Zealand. Getting pretty close to Samoa, though. Any Samoans out there following this? In my last report I said I was going to command the boat to go on a straight line instead of just commanding a heading. Well, I did that for a half of a day, but the current was still strong enough that the boat ended up spending most of its energy just trying to fight the current. So I went back to commanding a heading. Right now the heading command is 160 (20 degrees to the east of south) but it's still moving a little westward. I'm going to let it keep getting pushed west, even though there are more islands over there. I'll just have to keep a close eye on it.
8/30/2016: 1930 miles so far since re-launching on July 27. Yesterday the boat crossed the equator! You may have noticed the tracking map looks different now. Now it has arrows showing the boat's heading (thank you Ryan VanSickle). So if you look at the last several days of data, you'll see that the boat has been pointed directly south, even though it's been moving southwest. That's a result of the very strong current in this area. In the interest of making as much progress as possible, it was better to allow the current to push the boat around and just keep the boat's nose pointed south instead of trying to stay on a straight line. However, it's beginning to get close to some islands to the west of it's current position, so this morning I commanded it back to a straight line. Hopefully it's past the worst of the currents and it'll be able to make good progress on the straight line. Electrically, the boat seems to be holding steady. It's still struggling to charge up all the way during the day so I still have it throttled down, but at least it's not getting worse.
8/25/2016: 1500 miles so far since re-launching on July 27. 52.5 miles per day average, compared to 57 miles per day average on the California-Hawaii trip. Almost every morning the boat runs out of juice. I still can't figure out if it's something wrong with the boat or just cloudy weather or a combination of both. I do know that, a few days ago, it had a good day where the battery got charged up fully during the day and the motor ran all the way through the night. But since then it hasn't able to charge the battery all the way during the day. Whatever; it's still running. In a few days it should be crossing the equator!
8/11/2016: 838 miles so far since re-launching on July 27. Everything's going smoothly so far!
8/5/2016: I've been taking a break from obsessing about SeaCharger, which means I've been taking a break from writing updates. But SeaCharger is still alive and well, making good time. After launch, it went offshore of Hawaii for a few days to do some performance testing in the rather choppy water offshore. Now it's headed towards New Zealand. I'm hoping it at least makes it another 1000 miles.
7/27/2016: After recovering the boat, it sat in our vacation rental in Hawaii for a few days while we continued to vacation. Then once I had a few spare hours, I scraped off the barnacles, touched up a few areas with the anti-biofouling paint, tried to fix a corroded solar panel wire, and reprogrammed it with a couple of software changes. Then this morning we took it to lovely Hapuna Beach and put it back in the water. It was nice to be able to launch it in warm water with only tiny waves and without the pressure of thinking that it has to perform. However far it goes now will just be a bonus!
7/22/2016: All done! Seacharger arrived at Mahukona Harbor this evening. There were a few hiccups with the boat not wanting to let me take over with the R/C transmitter and manually steer it in, so those of you watching the tracking map will have seen it going back and forth a bit. In the end, I just aimed it right into the harbor and my wife jumped in with flippers and a snorkel to save it from the rocks and steer it the last few yards to where my brother and I pulled it out of the water. The boat was very clean! Just a few little barnacles. I'll post some pictures and stats over the next couple of days.
7/21/2016: 67.7 miles today, 22 miles to go to next waypoint. Looking good! Just one more day! And not a moment too soon, as tropical storm Darby is going to hit Hawaii the day after tomorrow. It looks like the boat will either arrive at Mahukona Harbor at about 6pm local time tomorrow or Kawaihae at 10 pm local time. Sunset is around 7pm. So I think I'll shoot for Mahukona. We'll recover the boat and then enjoy the sunset.
Our adventures in paradise today included walking to the bottom of Waipio Valley, which is quite the steep hike. A lot steeper and longer than we had anticipated. Oh, and it was hot and muggy and rainy. In the minds of some of our kids, hiking up and down a long, steep hill in these conditions is just about the greatest evil the world has to offer. Fortunately, at the bottom of the valley we met with the greatest good that the world has to offer (at least in the mind of our teenage girl): horses. Wild ones that come up to you and want to be petted. No, seriously. It was better than anything I could have made up. Disaster averted.
7/20/2016: 60.0 miles today, 89 miles to go. Good day today. Remember it's 89 miles to go to the next waypoint, but then another 60 or so till it actually reaches land. The battery got a full charge today for the first time in about 5 days due to the clouds being fairly minimal. I guess that also explains why two of my kids returned from snorkeling today with sunburnt backs. I'm sure they still think it was worth it. We saw a little shark (which only freaked out my oldest, the others were fine with it) and an amazing octopus that changed both color and texture instantaneously to match the coral it was sitting on. Having the technology to send a little boat across the ocean and communicate with it all along the way via satellite is definitely cool, but it sort of pales in comparison to watching an animal virtually disappear right before your eyes.
7/19/2016: 52.4 miles today, 149 miles to go. Today I flew to Hawaii to hopefully pick up the boat. Almost there! On the flight over, I could see why the battery hasn't been charging very well lately. Too many darn clouds. So it's still running at low throttle. I just hope that it doesn't get stuck in a strong current in the early morning hours when it's totally out of juice. Battery management is going to be important from here on.
7/18/2016: 49.6 miles today, 202 miles to go. A good enough day, but obviously the favorable current disappeared. Still seeing lots of clouds, so the battery still isn't fully charging, so it's been throttled down all day. I've really got to make sure that when it approaches Hawaii, it's got enough energy in the battery that it doesn't cut the motor off, as that could cause it to end up drifting onto the rocks.
7/17/2016: 81.8 miles today, 250 miles to go. Another great day, in spite of running out of juice in the early morning. Again, I'm going to blame it on clouds from Celia. We'll see if things improve tomorrow in terms of charging the battery. By the way, the number I'm giving for "miles to go" is actually not to the actual shore of Hawaii, but rather to the next waypoint, which is about 60 miles offshore. So the point is, you've gotta add 60 miles to that. So it's really 310 miles to go.
7/16/2016: 81.1 miles today, 326 miles to go. That's a whopping 3.4 miles per hour or 2.9 knots, folks! Only in the obscure, forgotten world of small unmanned solar-powered boats would that be considered fast, but whatever. I'll take what I can get. Actually, it would be going a little bit faster if I didn't have the motor throttled down a little. The battery hasn't been fully charged for a few days. I figure it's clouds from post-tropical storm Celia (I think that's the technical term for a hurricane in retirement). Maybe there's gunk on the solar panels. Who knows. Anyway, even with the motor throttled down a bit, we should have a good day tomorrow, too, if the current models are right.
7/15/2016: 71.6 miles today, 407 miles to go. Ahhh... MUCH better! Must be out of the bad current and into the good current. You know, I can't tell you how many times I've thought that the boat had some kind of terminal illness, whether it be the solar panels not charging the battery, the motor not running, the satellite modem not reporting, or the boat being snagged by some trash. But every time I think it's all over, the thing recovers and I realize I was just being paranoid.
I changed the report rate from once per two hours to once per hour, so if you look at the tracking map, that's why the upside-down teardrops are closer together. I figured it'll only cost another 40 bucks or so over the next week to get hourly updates, and I'd much rather know if something is wrong sooner. There's that paranoia again.
7/14/2016: 42.7 miles today, 479 miles to go. Too bad some of those 42.7 miles were actually in the wrong direction (motor stopped again). The boat's starting to make me nervous.
7/13/2016: 45.8 miles today, 517 miles to go. Well that was a pretty slow day. I'm going to blame it on currents again. That plus the fact that the motor shut off again for a few hours and I had to restart it. If the boat actually arrives in Hawaii I'm going to program it to restart the thruster automatically whenever it sees the speed drop below a certain amount. That would definitely help me sleep better. Literally.
7/12/2016: 60.6 miles today, 562 miles to go. Pretty decent day. THREE QUARTERS OF THE WAY THERE!!!
7/11/2016: 67.2 miles today, 622 miles to go. The battery saw its lowest voltage yet this morning, so low that it completely turned the motor off for an hour or so (intentionally, to save power). I'm assuming it's due to cloudiness yesterday not allowing the battery to fully charge. So if it's cloudy and the solar panels aren't producing much power, how can the boat still make such good time? It's because the power required to run the boat is proportional to the speed of the boat to the third power. So to go just 10% faster, you need 33% more power. Or to look at it in a more positive light, if you have only half the available power, the boat will still go 80% of full speed. So even though the solar panels may have been producing much less power than normal, it actually doesn't affect the boat speed that much. This same principle applies to cars, and it's a good reason not to speed on the highway: in addition to being dangerous, you have to burn a lot more gas to go just a little bit faster.
7/10/2016: 57.7 miles today, 690 miles to go. OK, much better today. The motor was a little weird this morning, not putting out much power. I think that once it throttles down, it sometimes has trouble throttling back up. Why did it throttle down in the first place? Well, if the battery voltage drops below a certain level, it'll throttle down to save power. For the past two weeks it's been able to make it through the night without the voltage dropping that low, but last night the battery voltage got lower than normal. Why? I think there might have been some cloudy weather yesterday causing it to not be able to recharge fully. And there might be some more cloudiness today. Anyway, I had to do another motor restart this morning and that seemed to get it going again.
Speaking of weather... there is one person who follows SeaCharger's progress even closer than I do, my mom, and she informed me today that there's a possible HURRICANE on its way to Hawaii!!! So that has me a little nervous. We'll have to monitor that. Not like there's much I can do to make the boat avoid the hurricane. I do pray a lot, though, and if the Lord has seen fit to bring the boat this far, then why not bring it through a hurricane?
7/9/2016: 46.8 miles today, 747 miles to go. Another slow day but the speed was picking up towards the end of the day, so I'm hoping for a better tomorrow.
7/8/2016: 49.5 miles today, 793 miles to go. Pretty dismal day. I think the boat's stuck in a current still. I tried some evasive maneuvers to try to get out of the current but probably should've just left it alone. You'll notice that even though it went 49.5 miles, it's only 43 miles closer than it was yesterday. That's because of all the zigging and zagging.
7/7/2016: 57.0 miles today, 836 miles to go. Right now it seems to be fighting a fairly strong current, so it's going pretty slow. Check out this website: https://earth.nullschool.net/ . It's about the coolest thing in the world. You can see winds, waves, currents, and other stuff, almost anywhere on earth.
7/6/2016: 56.7 miles today, 893 miles to go. The motor shut off again this morning, so we lost some ground there.
7/5/2016: 68.4 miles today, 949 miles to go.
7/4/2016: 68.6 miles today, 1018 miles to go. Average speed over the entire trip so far: 57 miles per day.
7/3/2016: 53.9 miles today, 1087 miles to go. A little slower today.
7/2/2016: 66.4 miles today, 1141 miles to go. HALFWAY THERE!
7/1/2016: 73.3 miles today, 1207 miles to go. Woo hoo! Must've caught a nice bit of current.
6/30/2016: 69.6 miles today, 1280 miles to go. Just keep swimming. Just keep swimming.
6/29/2016: 64.6 miles today, 1350 miles to go. 1,000 miles down!
6/28/2016: 66.1 miles today, 1414 miles to go. Just truckin' along.
6/27/2016: 58.7 miles today, 1481 miles to go. Another good day.
6/26/2016: 59.7 miles today, 1539 miles to go. A THIRD OF THE WAY THERE! The boat was really moving today, but unfortunately the motor shut off for a few hours until I was able to restart it again. It had done that once before. Don't know why, but as long as it does it infrequently, it's fine by me. Anyway, in spite of the motor shutting off, it still had a good day.
6/25/2016: 59.3 miles today, 1598 miles to go. Another good day.
6/24/2016: 57.9 miles today, 1658 miles to go. Not bad mileage, especially considering that I left the throttle at 90% for most of the day. Normally I bring the throttle down to 90% at night and then raise it back up to 100% in the morning. This is because there isn't quite enough battery capacity to go all night at full throttle. Last night I brought the throttle down to 90% but then I went camping with my kids in a place without phone service, so I had no way to bring the throttle back to 100% this morning. But on the bright side, my small kids did a fantastic job on our 8-mile hike with no snacks and minimal water. And we counted 91 banana slugs on the hike!
6/23/2016: 54.1 miles today, 1716 miles to go. Certainly a little slower today, but still going strong.
6/22/2016: 67.6 miles today, 1770 miles to go. A QUARTER OF THE WAY THERE!!! And the most miles covered in a day so far! I also saw the highest reported speed so far (1.47 m/s, or 3.29 mph). What makes it go faster some days? I think it's mostly the wind. I noticed early in testing that a crosswind causes the boat to lean pretty hard to one side, which I assumed would slow it down (especially if it leans far enough for the side of the solar panel deck to get dragged through the water). But from what I've seen so far during its journey to Hawaii, it likes to have a crosswind. I believe the boat is actually sailing. Below is a graph of the boat's speed vs. the absolute value of its roll angle. Not totally conclusive, but there seems to be trend showing that speed increases as the roll angle (which is caused by a crosswind) increases.
Some of you have been asking for more telemetry. So the next picture shows the voltage and current history for the journey so far. The current shown is the current being produced by the solar panels. Some of that current goes to charging the battery, some of it goes to running the motor, and a little bit of it goes to running the electronics and the rudder servo. Unfortunately I don't have individual current sensors for those different loads. But you can sort of deduce what the current going into the motor by looking for times when the battery is fully charged (which is when you see the battery voltage above 20 volts). At these times, there's no current going into the battery, so the only things drawing current are the electronics, the rudder servo, and the motor. The motor probably accounts for 95% of that. So you can tell that the motor draws about 1 amp * 20 volts = 20 watts at full throttle. Actually, I don't really trust my current sensor, so I would put a healthy uncertainty on that number.
6/21/2016: 60.7 miles today, 1837 miles to go. The boat's really moving these past couple days!
6/20/2016: 62.6 miles today, 1898 miles to go. Another good day. It must be really wavy or else the waves are coming from a weird direction because the boat's rudder is really active trying to keep the boat on a straight track. But the speed is good.
6/19/2016: 50.3 miles today, 1960 miles to go. The boat moved along at a pretty good clip today. I think the weather is finally cooperating and I finally know how to manage the throttle. I put it back on a slightly more southerly heading to take advantage of wind coming from the north.
6/18/2016: 47.3 miles today, 2009 miles to go. The thruster is not being very predictable. It seems like I have to restart it every now and then to get it to give full power. So the boat speed isn't what it should be, but oh well. It's still moving. One week completed!
6/17/2016: 43.4 miles today, 2057 miles to go. The winds out there should be from a more favorable direction now, so this morning the boat started tracking straight to its next waypoint offshore of Hawaii. Previously it was heading more southerly to avoid wind. With it tracking a straight line to the next waypoint, there shouldn't be anymore crookedness in its path.
6/16/2016:37.3 miles today, 2098 miles to go. Rather slow progress due to a headwind. That is forecasted to switch to a tailwind tomorrow, so hopefully we'll go faster then.
6/15/2016: 50.4 miles today, 2128 miles to go. Another rather uneventful day. My friend Ryan VanSickle put together a much better map for tracking this thing (see the link above). Thank you Ryan! If you hover over each point on the map, it'll tell you what time the boat was there, in Zulu time. If you're in the Pacific time zone, subtract seven hours from Zulu time to get your local time. I think he's updating the map a couple of times per day.
6/14/2016: 52.1 miles today, 2165 miles to go. Nothing exciting to report, which is fine by me. It's just chugging along. If you're wondering why it's not going in a straight line, it's because it's currently in "heading" mode, where it just attempts to keep the nose pointed at a certain heading (currently 230 degrees). But even if the nose is pointed at a perfectly constant heading, the wind and currents will still push it around, hence the unsteady track.
It also has a waypoint-tracking mode, where it would try to go straight to the next waypoint. The next waypoint is off the coast of Hawaii, and the heading to get to that waypoint would be something like 250 degrees. But I'm trying to get to more favorable weather towards the south, which is why I'm having it head slightly more towards the south. Once it gets down south a little more, I'll put it back in waypoint mode. There's also a wind-following mode, where it tries to keep the wind at its tail. How does it know where the wind is coming from? Glad you asked. Because of that awful giant solar panel deck on the top of the boat, it tends to roll left when the wind is blowing from the right and right when the wind is blowing from the left. So the wind-following mode just moves the rudder in proportion to how much the boat is rolled over, which tends to align the boat with the wind and level the boat. It can automatically go either upwind or downwind, depending on how I adjust a certain parameter. I've never actually tested this wind-following stuff, so it may not actually work, but it sounds cool at least. I'll probably try it out once the wind starts blowing in a direction I want to go.
6/13/2016: 39.4 miles today, 2201 miles to go. Seacharger is back in the water! After a very short first attempt on May 30th, we fixed some software problems and launched the boat again on June 11th from Half Moon Bay, CA. The water off the coast of California is pretty rough right now, but for the most part the boat is doing well. Today (June 13) I had some major scares, first with the boat failing to report twice in a row, and then finding that the motor had turned off for some reason. This is all extremely nerve-wracking. But after the boat miraculously coming back online and resetting the motor, all seems to be going well. About 100 miles down, 2200 to go! What, me worry?
In coming days we'll probably have a better tracking map. But for now this is all we've got.
Fun Fact: Did you know that there's not one but TWO solar-powered unmanned boats crossing oceans at this very moment? Check this out: www.solar-voyager.com/
6/20/2016: 62.6 miles today, 1898 miles to go. Another good day. It must be really wavy or else the waves are coming from a weird direction because the boat's rudder is really active trying to keep the boat on a straight track. But the speed is good.
6/19/2016: 50.3 miles today, 1960 miles to go. The boat moved along at a pretty good clip today. I think the weather is finally cooperating and I finally know how to manage the throttle. I put it back on a slightly more southerly heading to take advantage of wind coming from the north.
6/18/2016: 47.3 miles today, 2009 miles to go. The thruster is not being very predictable. It seems like I have to restart it every now and then to get it to give full power. So the boat speed isn't what it should be, but oh well. It's still moving. One week completed!
6/17/2016: 43.4 miles today, 2057 miles to go. The winds out there should be from a more favorable direction now, so this morning the boat started tracking straight to its next waypoint offshore of Hawaii. Previously it was heading more southerly to avoid wind. With it tracking a straight line to the next waypoint, there shouldn't be anymore crookedness in its path.
6/16/2016:37.3 miles today, 2098 miles to go. Rather slow progress due to a headwind. That is forecasted to switch to a tailwind tomorrow, so hopefully we'll go faster then.
6/15/2016: 50.4 miles today, 2128 miles to go. Another rather uneventful day. My friend Ryan VanSickle put together a much better map for tracking this thing (see the link above). Thank you Ryan! If you hover over each point on the map, it'll tell you what time the boat was there, in Zulu time. If you're in the Pacific time zone, subtract seven hours from Zulu time to get your local time. I think he's updating the map a couple of times per day.
6/14/2016: 52.1 miles today, 2165 miles to go. Nothing exciting to report, which is fine by me. It's just chugging along. If you're wondering why it's not going in a straight line, it's because it's currently in "heading" mode, where it just attempts to keep the nose pointed at a certain heading (currently 230 degrees). But even if the nose is pointed at a perfectly constant heading, the wind and currents will still push it around, hence the unsteady track.
It also has a waypoint-tracking mode, where it would try to go straight to the next waypoint. The next waypoint is off the coast of Hawaii, and the heading to get to that waypoint would be something like 250 degrees. But I'm trying to get to more favorable weather towards the south, which is why I'm having it head slightly more towards the south. Once it gets down south a little more, I'll put it back in waypoint mode. There's also a wind-following mode, where it tries to keep the wind at its tail. How does it know where the wind is coming from? Glad you asked. Because of that awful giant solar panel deck on the top of the boat, it tends to roll left when the wind is blowing from the right and right when the wind is blowing from the left. So the wind-following mode just moves the rudder in proportion to how much the boat is rolled over, which tends to align the boat with the wind and level the boat. It can automatically go either upwind or downwind, depending on how I adjust a certain parameter. I've never actually tested this wind-following stuff, so it may not actually work, but it sounds cool at least. I'll probably try it out once the wind starts blowing in a direction I want to go.
6/13/2016: 39.4 miles today, 2201 miles to go. Seacharger is back in the water! After a very short first attempt on May 30th, we fixed some software problems and launched the boat again on June 11th from Half Moon Bay, CA. The water off the coast of California is pretty rough right now, but for the most part the boat is doing well. Today (June 13) I had some major scares, first with the boat failing to report twice in a row, and then finding that the motor had turned off for some reason. This is all extremely nerve-wracking. But after the boat miraculously coming back online and resetting the motor, all seems to be going well. About 100 miles down, 2200 to go! What, me worry?
In coming days we'll probably have a better tracking map. But for now this is all we've got.
Fun Fact: Did you know that there's not one but TWO solar-powered unmanned boats crossing oceans at this very moment? Check this out: www.solar-voyager.com/