Day 20

Jim and I learned a lot from last night's mission even though it go stuck twice in the snow, stuck in stop mode, and lost all of its waypoints.  Yeah it sounds like a horrible run and it was in terms of not doing exactly what we thought but because of what we learned I would say it was one of our better ones.  Here is why:  When the CR got stuck I could first figure it out that it was stuck by looking at printouts the robot was giving me on the computer which I confirmed by seeing that the robot was not moving.  So setting the robot back to manual mode I first backed it up for about half a second and then ran it forward and turning for about 1 second before set it back to autonomous mode, which is all that it needed to be on its way again.  Jim also figured out that it was probably getting stuck because the robot was trying to make such a hard turn while going slow that the inside wheels would be probably stopped while the outside one where spinning, digging itself in.  Another thing discovered with the turns is if the robot decide to stop (the turn taking more power) that the robot could not restart itself because there was some kind of flag in the code that could not be reset for that condition therefore the robot would just sit.  The lost of the robot's waypoints we was a bit perplexing but we are guessing it was due to a lost of power to the rabbit board (the microcontroller) because the battery voltage dropped to low.  Not sure if that is what was as it is the first time we have seen it happen and hopefully it will happen again.

Today we brought the robot in for a few code changes: removed the possibility for the robot to get stuck in the program's dead spot, updated the panel voltage and current calibration curves (they where not much different) and increased the duty cycle for better power tracking of the solar panels due temperature changes.  Also we have noticed that panel 1 is hardly producing any power for some time now so we checked its boost converter and discovered that it took a hard hit at some point and melted.  Ben spent this evening finishing building up a replacement and installing it.  After which Jim and I ran a short test tonight to see how it worked and how the max power point tracking was working with the changed duty cycle.  Both looked great or better than they have looked in the past few days!  Tomorrow we will do a longer run with more sun.

Melted chip insert on the booster converter board.

Ben working the booster converter replacement.