Today I took AquaBitsTwo out for its second test in open water. These are the results, notes, and lessons I learned…
- Wind. I was unaffected by this during the first test and didn’t need to deal with it. Today there was some wind. Not very much, just a few miles per hour. But my motor mount and rudder acted like sails and the boat wanted to align with the wind. Boat bottom is flat. I guess that’s what fins and keels are for, eh? Couldn’t solve that problem on the water, but I did increase the propeller speed to mitigate it. In general, I might be driving the boat too slowly. Would probably be easier to do my initial tests and tuning at higher speeds to overcome things like wind or rudders not pushing the boat with enough force for a proper turn.
- Before I increased the propeller speed, the boat was sailing as if it were going to the wrong waypoint. Right now I can’t say if it was a problem of GPS code, or if it was simply trying and failing to overcome the wind. This would have been obvious with a terrestrial rover. Interesting problem.
- I spent a lot of time trimming and tuning.
- Realized I have no way of telling if the Arduino servo controls are correct, what if I had placed the servo horn on backwards? I will be adding a test sequence during startup, maybe turn right for a few seconds so I have positive confirmation it is correct.
- Something is triggering the boat to go in to automatic mode and run it’s “drive straight to get a heading” function. I’m pretty sure the transceiver’s trim button is doing this and possibly something else.
- I chose boats as a robotic platform because I didn’t think it would have as many obstacles as land based rovers do. But I’m seeing wind now as an obstacle. It’s just not as obvious visually as lampposts and mailboxes. Someday(hopefully), current will be an obstacle to overcome as well.
- My drone won’t fly if the battery is less than 15 degrees Celsius. I did not know that. No fun aerial photos. Next time I’ll leave it in the car until I am ready.
- Lots of boaters on the water at dawn on Saturdays. There were at least six nearby. Don’t they know it’s robot season?