Tuning your Robot
Pathfinder itself is simply a library for manipulating input and output information to get the robot to perform a specified goal. Such, Pathfinder doesn’t care about what units are what units or which direction the robot needs to move to do whatever. As a result of this abstraction, it’s often neccesary to tune your robot.
TABLE OF CONTENTS
Drivetrain Tuning
Tuning the drivetrain is a must. Here’s some guidelines on how you can tune your drivetrain’s configuration like the professional you are.
Tuning a Meccanum or Tank Drive
Meccanum and tank drives are both very easy to tune. The core concept here that you need to recognize is that tuning is designed to make sure that each motor spins in the correction direction when given a certain power value. The kinematics provided in Pathfinder doesn’t account for the possibility that a motor might be inverted. If you tell a robot to move forwards using Pathfinder, Pathfinder will say that every drive wheel should get 1.0 power - max speed forwards, that is. However, if your robot hasn’t been tuned whatsoever, your robot won’t turn forwards - rather, it’ll do donuts until you turn it off. This is because (on most robots, at least) the left (or right, it depends) half of your drivetrain spins in the opposite direction as the other side. Thankfully, there’s a pretty easy fix to this problem.
- Flip the robot on its side (or upside-down, just be careful not to break it!)
- Create a basic program that sets the power of each motor to 0.3.
- Every motor should be spinning forwards now. If they’re not, you need to invert it.
- Write down each motor and the direction it was spinning.
- In your code, make sure that the motors that should be inverted have the power values they recieve multiplied by negative 1 before setting power to the motor.
- Run the four-wheel-forwards test again. Each wheel should spin in the same direction now.