Differential Steering with a single dual axis Joystick in Arduino

Just a simple arduino library to use differential steering with two motors. The compute is fully based in the impulseAdventure code.

Install the library & Import

Download this repository as a .zip file and from the Arduino IDE go to Sketch -> Include library -> Add .ZIP Library.

You can import the library in your code using the Arduino IDE going to Sketch -> Include library -> DifferentialSteering or directly writing the include statement in your code:

#include "DifferentialSteering.h"

Features

The library works with [-127, 127] range, both the input and output methods, i. e., you will need to map your X,Y joystick values to [-127,127] prior the compute, and the result will also be in [-127, 127].

Joystick library

The example sketch uses the Joystick library I wrote to control with a single dual axis joystick.

Using the library

In examples/differentialSteringSingleJoystick.ino yo can see the library in action.

First, initialize a DifferentialSteering object with the proper pivot limit:

    int fPivYLimit = 32;
    DifferentialSteering DiffSteer;

    void setup () {
        DiffSteer.begin(fPivYLimit);

Then, compute differential steering with the joystick outputs. Keep in mind that the inputs of computeMotors method have to be mapped to [-127, 127]:

    int XValue = map(yourXRaw, yourLowRange, yourHighRange, -127, 127);
    int YValue = map(yourYRaw, yourLowRange, yourHighRange, -127, 127);
    DiffSteer.computeMotors(XValue, YValue);

Ultimatelty, do something with motor outputs, like mapping to your desire range (e.g. PWM value). The output range will be [-127, 127]:

    int leftMotor = DiffSteer.computedLeftMotor();
    int rightMotor = DiffSteer.computedRightMotor();