2 tracking wheel+ IMU(inertial) odometry

[sarah_97963A]

@tek

Does anyone have any insight on 2 tracking wheels + IMU for odometry?

I use that for my team’s robots. You only need two tracking wheels perpendicular to each other when you use imu for heading since the two parallel tracking wheels in the three tracking wheel setup are for heading calculations. See the post below:

@CarlosStewart

Basically, the algorithm doesn’t really need 3 tracking wheels, it needs 1 to measure forward/backward movement and 1 to measure left/right movement, and something to measure angle change. Because this algorithm was developed before the VEX Inertial Sensor came out, the Pilons opted to measure angle with two parallel wheels instead of the gyroscope. Now, however, the inertial sensor is a good replacement for the parallel wheels.

@tek

I noticed how they have 3 tracking wheels namely because of their strafing ability

The drive type does not matter, you can still use two tracking wheels + imu even if you have an x drive. I sometimes use three tracking wheels just so that I can average the readings from the two parallel tracking wheels and place the third one at the center of the robot.