Meadow.Foundation.Motors.Stepper.GpioStepper

Meadow.Foundation.Motors.Stepper.GpioStepper

Digital input stepper motor controller

The GpioStepper library is included in the Meadow.Foundation.Motors.Stepper.GpioStepper nuget package and is designed for the Wilderness Labs Meadow .NET IoT platform.

This driver is part of the Meadow.Foundation peripherals library, an open-source repository of drivers and libraries that streamline and simplify adding hardware to your C# .NET Meadow IoT applications.

For more information on developing for Meadow, visit developer.wildernesslabs.co.

To view all Wilderness Labs open-source projects, including samples, visit github.com/wildernesslabs.

Installation

You can install the library from within Visual studio using the the NuGet Package Manager or from the command line using the .NET CLI:

dotnet add package Meadow.Foundation.Motors.Stepper.GpioStepper

Usage

private IStepperMotor stepper;

private bool UseStepDirConfiguration { get; set; } = true;

public override Task Initialize()
{
    if (UseStepDirConfiguration)
    {
        // use a drive configured for STEP/DIR GPIOs
        stepper = new StepDirStepper(
            Device.Pins.D15.CreateDigitalOutputPort(),
            Device.Pins.D14.CreateDigitalOutputPort(),
            stepsPerRevolution: 200);
    }
    else
    {
        // use a drive configured for CW/CCW GPIOs
        stepper = new CwCcwStepper(
            Device.Pins.D15.CreateDigitalOutputPort(),
            Device.Pins.D14.CreateDigitalOutputPort(),
            stepsPerRevolution: 200);
    }

    return base.Initialize();
}

public override Task Run()
{
    // return RunUntilCancelled();
    // return RunForSpecifiedTime();
    // return RunToSpecificPositions();
    return RotateSpecifiedAmount();
}

private async Task RunUntilCancelled()
{
    var direction = RotationDirection.Clockwise;
    var rate = new AngularVelocity(1, AngularVelocity.UnitType.RevolutionsPerSecond);

    while (true)
    {
        var tokenSource = new CancellationTokenSource();

        Resolver.Log.Info($"Start running...");
        var task = stepper.Run(direction, rate, tokenSource.Token);

        Resolver.Log.Info($"wait for 3 seconds...");
        await Task.Delay(3000);

        Resolver.Log.Info($"cancelling motion...");
        tokenSource.Cancel();

        Resolver.Log.Info($"wait for motion to stop");
        task.Wait();

        Resolver.Log.Info($"motion stopped");

        direction = direction switch
        {
            RotationDirection.CounterClockwise => RotationDirection.Clockwise,
            _ => RotationDirection.CounterClockwise
        };

        await Task.Delay(500);
    }
}

private async Task RunForSpecifiedTime()
{
    while (true)
    {
        var direction = RotationDirection.Clockwise;
        var rate = new AngularVelocity(1, AngularVelocity.UnitType.RevolutionsPerSecond);

        Resolver.Log.Info($"Run for 2 seconds...");
        await stepper.RunFor(TimeSpan.FromSeconds(2), direction, rate);

        direction = RotationDirection.CounterClockwise;
        rate = new AngularVelocity(2, AngularVelocity.UnitType.RevolutionsPerSecond);

        await stepper.RunFor(TimeSpan.FromSeconds(2), direction, rate);
    }
}

private async Task RotateSpecifiedAmount()
{
    while (true)
    {
        for (var turns = 0.5d; turns <= 5; turns += 0.5)
        {
            Resolver.Log.Info($"Moving {turns:0.0} revolutions");

            var direction = RotationDirection.Clockwise;
            var rate = new AngularVelocity(4, AngularVelocity.UnitType.RevolutionsPerSecond);

            await stepper.Rotate(new Angle(turns, Angle.UnitType.Revolutions), direction, rate);

            await Task.Delay(1000);
        }
    }
}

private async Task RunToSpecificPositions()
{
    RotationDirection direction;

    var rate = new AngularVelocity(2, AngularVelocity.UnitType.RevolutionsPerSecond);

    // turn in smaller and smaller degree increments
    var increments = new double[] { 180, 90, 60, 45, 30 };

    while (true)
    {
        direction = RotationDirection.Clockwise;

        Resolver.Log.Info($"{direction}");

        foreach (var increment in increments)
        {
            Resolver.Log.Info($"Moving in increments of {increment} degrees");

            await stepper.GoTo(new Angle(0), direction, rate);
            await Task.Delay(1000);

            var nextPosition = 0d;

            while (nextPosition < 360)
            {
                Resolver.Log.Info($"Moving to {nextPosition} degrees");

                nextPosition += increment;

                await stepper.GoTo(new Angle(nextPosition, Meadow.Units.Angle.UnitType.Degrees), direction, rate);
                await Task.Delay(1000);
            }
        }

        await Task.Delay(3000);

        direction = RotationDirection.CounterClockwise;

        Resolver.Log.Info($"{direction}");

        foreach (var increment in increments)
        {
            Resolver.Log.Info($"Moving in increments of {increment} degrees");

            var nextPosition = 360d;

            await stepper.GoTo(new Angle(0), direction, rate);
            await Task.Delay(1000);

            while (nextPosition > 0)
            {
                Resolver.Log.Info($"Moving to {nextPosition} degrees");

                nextPosition -= increment;

                await stepper.GoTo(new Angle(nextPosition, Meadow.Units.Angle.UnitType.Degrees), direction, rate);
                await Task.Delay(1000);
            }
        }

        await Task.Delay(3000);

        Resolver.Log.Info($"--- Cycle complete ---");
    }
}

How to Contribute

• Found a bug? Report an issue
• Have a feature idea or driver request? Open a new feature request
• Want to contribute code? Fork the Meadow.Foundation repository and submit a pull request against the develop branch

Need Help?

If you have questions or need assistance, please join the Wilderness Labs community on Slack.

About Meadow

Meadow is a complete, IoT platform with defense-grade security that runs full .NET applications on embeddable microcontrollers and Linux single-board computers including Raspberry Pi and NVIDIA Jetson.

Build

Use the full .NET platform and tooling such as Visual Studio and plug-and-play hardware drivers to painlessly build IoT solutions.

Connect

Utilize native support for WiFi, Ethernet, and Cellular connectivity to send sensor data to the Cloud and remotely control your peripherals.

Deploy

Instantly deploy and manage your fleet in the cloud for OtA, health-monitoring, logs, command + control, and enterprise backend integrations.