MAXSwerve Python Template originally from: https://github.com/edubu/MAXSwerve-Python-Template

The python implementation of REV Robotics MAXSwerve Modules as adapted from the REV Robotics CPP Template for use in an environment using RobotPy. Suitable for FIRST Robotics Teams that want to utilize swerve drive and are using Python for their robot code. As Python is now officially supported by FRC as of 2024, a python adaptation is necessary.

Requirements

Windows 7 (64-bit) or newer

Windows is only necessary for programming the CAN IDs using the REV Hardware Client

Installation & Setup

Install Python & RobotPy

Follow the FRC Installation Guide for step by step instructions to get the environment setup for python in FRC.

Clone this repository

The commands below will download this repository and install all of the necessary packages to your environment which will then be transferred over to the RoboRio

user@user:~$ git clone https://github.com/edubu/MAXSwerve-Python-Template.git
user@user~$ py -3 -m robotpy sync

Setup the SparkMax Controllers using CAN

The SparkMAX require the use of CAN to communicate with the encoders. If seeking guidance wiring with CAN, checkout this guide to help through the process.

After the wiring has been completed, you will need to connected to each SparkMax using the REV Hardware Client

Follow this guide to program the SparkMax controllers to their unique CAN IDs

Modify the SwerveDrive Parameters

The swerve drive parameters are located in constants.py and will be used to communicate with the SparkMax controllers and setup the kinematics of the chassis.

Change the CAN ID parameters

constants.py

# SPARK MAX CAN IDs
kFrontLeftDrivingCanId = 2
kRearLeftDrivingCanId = 8
kFrontRightDrivingCanId = 4
kRearRightDrivingCanId = 6

kFrontLeftTurningCanId = 3
kRearLeftTurningCanId = 1
kFrontRightTurningCanId = 5
kRearRightTurningCanId = 7

Set the dimensions of the chassis

constants.py

# Chassis configuration
kTrackWidth = 0.6953 # Distance between centers of right and left wheels on robot METERS
kWheelBase = 0.6953 # Distance between centers of front and back wheels on robot METERS

Set the pinion gear used in the MaxSwerve Module

constants.py

# The MaxSwerve module can be configured with one of the three pinion gears: 12T, 13T, or 14T.
# This changes the drive speed of the module ( a pinion gear with more teeth will result in a robot that drives faster)
kDrivingMotorPinionTeeth = 13

FAQs

Do I need to use the NavX Gyroscope?

No, the NavX gyroscope was simply used because we had it available. You can use any gyro by simply changing the following to connect to your available hardware

 # NavX Gyroscope
self.gyro = navx.AHRS(wpilib.SerialPort.Port.kUSB)

# Example Analog Gyroscope
self.gyro = wpilib.AnalogGyro(analogChannel)

What controllers are being used?

In this template, an XboxController class is utilized to control the robot. The axis are predefined to control it and utilize SlewRateLimiters as well as a Deadband to facilitate smooth driving.

Resources

REV Robotics MAXSwerve Module
REV Robotics MAXSwerve Docs
REV Robotics MAXSwerve CPP Template
RobotPy Docs