The team I coach recently started experiencing a problem I can’t explain and I would love feedback on how to guide the team.
For the autonomous skills, the team developed a program where the robot drives to the corner, waits for the team to launch the triballs via a launcher, and then navigates to cross the middle bar and push the triballs under the net. The problem the team encountered is if they run the program without launching any triballs, the robot follows the yellow path below. If the team launches triballs, the robot follows the orange path instead. Namely, it doesn’t drive as close to the center and the robot occasionally hits the corner of the blue goal and impacts the robot turning straight.
At first we thought the inertial sensor didn’t finish calibrating before the team started launching. The team put a wait at the start of the code, but that didn’t make a difference. Our other coach thought maybe it had something to do with the power draw of the launcher motor under load impacting the power available to drive and that was the reason the robot didn’t back up far enough. The documentation for the V5 motors suggests that shouldn’t be the case but I don’t know if others have experienced that.
I don’t remember the timing, but the team added an 8th motor to the robot to get additional autonomous win points during the 15-second autonomous. That motor isn’t used in the autonomous skills, but that is the only thing I remember the team changing recently.
Does anyone have any ideas why the robot follows different paths when launching versus not launching? In case it helps, all robot turns use the turn to heading command so any small movement of the robot while launching shouldn’t meaningfully impact the path the robot drives.
Here is the statement from the programmers on the team:
To launch triballs, our robot uses a gear ratio flywheel launcher. When running our autonomous code without firing triballs the code works perfectly. It sweeps the triballs away from the center so we can cross over the center bar and we can push the triballs into the goal. On the other hand, when we fire triballs, the robot doesn’t go the same distance and the turn to heading doesn’t seem to be accurate. We have tried changing the distance and waiting before firing but these didn’t work. We don’t have any idea what to try. Thank you for your time. Sincerely, the programming team.
Ok - here is where I am scratch my head - before you start spinning your fly wheel, you are against the field perimeter - why? Why not start from match load bar if your robot size permits it? Because it seems to me you are trying to set your robot to shoot in correct direction with a lot of movement.
I have not tried block coding, but do you validate what direction your robot is actually facing before making the turn. If you have omniwheels, you can expect some overturning - more so since you are dropping objects on the bot. A quick and dirty move is to sample your robot’s direction and see if it is actually pointing where you want, if not correct back with a slow turn back - like really slow 25% to check. You can send info to the V5 joystick controller to inform you which way your robot is facing after turn for quick debugging.
Wayback when our team did gyro turns at MS, that is the technique they employed for their autonomous in Turning Point …
But best advice keep paths simple, use debugging information so you can get feedback if your robot is doing what you really want it to.
also, based on the information provided, it is unclear if the path provide at beginning of this topic was best recollection or actual plot (video the run - place white tape pieces of your targets and see visually how far it is off - another debugging path debugging technique in 2019.
