Quote:
Originally Posted by AdamHeard
This is actually pretty false. The code for a "unicorn drive" (darn JVN for coming up with such a silly name) is actually substantially shorter than most other crab codes. The initial derivation is hard, but once it's done the code is very short, and one function works for ALL cases of input (there is no translation mode, steering mode, etc... Just one mode). The error calculation for going over zero is only trivially harder than normal error calculation, and many teams decide to never reverse module drive direction for mechanical reasons so that function is a nonissue.
Also, you could just take the lazy way and copy the functions Ether posted.
We converted our 2008 crab prototype to an independent drive and steer crab, it runs, and the code is short. Most other statements in this thread are pure speculation.
|
The initial derivation does indeed give you one equation, but that one equation has a lot of variables. The number of variables is so large it would be difficult to manipulate them all for the entirety of the match without really good (expensive) joysticks, and even then, it is sometimes just easier to have constants that can be used in place of certain variables. this also has the potential advantage of making the robot respond faster for two reasons. By pre-calculating certain parts of the equation, the code can execute faster, and, since certain values plugged in for some variables can result in the angle output for some modules return the same value despite the other inputs changing, by adding modes to set the values so that this is the case, mechanical reaction time improves at the cost of reduced maneuverability.
I hope that makes sense, If unicorn drive were Moby Dick, I fear I would have to be Captain Ahab, I hope I haven't reached the rambling stage yet.