axis-motion-velocity-via-analoginput.cs

Note

See Motion: Point-to-Point 📜 for a detailed explanation of this sample code.

Warning

This is a sample program to assist in the integration of the RMP motion controller with your application. It may not contain all of the logic and safety features that your application requires. We recommend that you wire an external hardware emergency stop (e-stop) button for safety when using our code sample apps. Doing so will help ensure the safety of you and those around you and will prevent potential injury or damage.

The sample apps assume that the system (network, axes, I/O) are configured prior to running the code featured in the sample app. See the Configuration page for more information.

/*  This sample demonstrates how to control axis velocity dynamically using an analog input value.
    The analog input value (0 to 65536 for a 16-bit input) is mapped to a velocity range.
    This was created using the EL3002 Analog Input module but works with many other modules.
*/
 
using RSI.RapidCode; // RSI.RapidCode.dotNET;
using System.Threading;
 
Console.WriteLine("📜 Axis Motion: Velocity via Analog Input");
 
// set sample config params
const double ACCELERATION  = 100;
const double MAX_VEL       = 10;
const double MAX_ANALOG    = 65536;  // 16-bit analog input
const int RUN_TIME_SECONDS = 20;     // how long to run the velocity control loop
 
// get rmp objects
MotionController controller = MotionController.Get();
 
try
{
    Helpers.CheckErrors(controller);
 
    // check is network is started
    if (controller.NetworkStateGet() != RSINetworkState.RSINetworkStateOPERATIONAL)
    {
        Console.WriteLine("Network not started. Please start it before running this app.");
        return;
    }
 
    // get phantom axis
    Axis axis = controller.AxisGet(Constants.AXIS_1_INDEX);
    Helpers.CheckErrors(axis);
 
    // get node
    var node = controller.NetworkNodeGet(nodeNumber: 0);
    Helpers.CheckErrors(node);
 
    // configure axis
    Helpers.PhantomAxisReset(axis);
    axis.AmpEnableSet(true);
 
    // print sample info
    Console.WriteLine($"Max Speed = {MAX_VEL}");
    Console.WriteLine($"Running for {RUN_TIME_SECONDS} seconds...\n");
 
    // control velocity based on analog input
    var startTime = DateTime.Now;
 
    while ((DateTime.Now - startTime).TotalSeconds < RUN_TIME_SECONDS)
    {
        // get analog input value and normalize to 0.0 - 1.0
        double analogValue = node.AnalogInGet(analogChannel: 0);
        double normalizedValue = analogValue / MAX_ANALOG;
 
        /*
        ┌────────────────────────────────────────────────────┐
        │    Analog Input Value Maps Linearly to Velocity    │
        │                                                    │
        │  Analog:   0 ............................ 65,536   │
        │  Velocity: 0 ............................ MAX_VEL  │
        └────────────────────────────────────────────────────┘
        */
 
        // map analog input linearly to velocity (0 to MAX_VEL)
        double velocity = normalizedValue * MAX_VEL;
 
        axis.MoveVelocity(velocity, ACCELERATION);
 
        Thread.Sleep(1);  // prevent cpu spin
    }
 
    // cleanup
    Helpers.AbortMotionObject(axis);
}
// handle errors as needed
finally
{
    controller.Delete();  // dispose
}