APIs, concepts, guides, and more
Motion: Path

Learn how to work with Path motion in C#.

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.


In this page:


📜 Motion: Path

Learn how to set up and run Path Motion 📖 with a Robot object. Shows how to create kinematic models, program path movements using lines and arcs, and execute coordinated multi-axis motion.

/* This sample demonstrates how to set up and run path motion with a Robot object.
Shows how to create kinematic models, program path movements using lines and arcs,
and execute coordinated multi-axis motion.
*/
using RSI.RapidCode; // RSI.RapidCode.dotNET;
using System.Threading;
Console.WriteLine("📜 Motion: Path");
// get rmp objects
try
{
Helpers.CheckErrors(controller);
// set robot axis labels
const string xLabel = "X-Axis";
const string yLabel = "Y-Axis";
const string zLabel = "Z-Axis";
const string aLabel = "A-Axis";
const string bLabel = "B-Axis";
const string cLabel = "C-Axis";
// get the 6 axis needed for XYZABC robot
Axis xAxis = controller.AxisGet(Constants.AXIS_0_INDEX);
Axis yAxis = controller.AxisGet(Constants.AXIS_1_INDEX);
Axis zAxis = controller.AxisGet(Constants.AXIS_2_INDEX);
Axis aAxis = controller.AxisGet(Constants.AXIS_3_INDEX);
Axis bAxis = controller.AxisGet(Constants.AXIS_4_INDEX);
Axis cAxis = controller.AxisGet(Constants.AXIS_5_INDEX);
// configure phantom axes
// set axis labels
xAxis.UserLabelSet(xLabel);
yAxis.UserLabelSet(yLabel);
zAxis.UserLabelSet(zLabel);
aAxis.UserLabelSet(aLabel);
bAxis.UserLabelSet(bLabel);
cAxis.UserLabelSet(cLabel);
// create multi-axis object for joints
MultiAxis jointsMultiAxis = controller.MultiAxisGet(0);
Axis[] axes = [ xAxis, yAxis, zAxis, aAxis, bAxis, cAxis ];
jointsMultiAxis.AxesAdd(axes, axes.Length);
jointsMultiAxis.ClearFaults();
// create kinematic model with 6-axis configuration
const LinearUnits units = LinearUnits.Meters;
const string modelName = "RSI_XYZABC_Meters";
const double scaling = 1.0;
const double offset = 0.0;
LinearModelBuilder builder = new(modelName);
builder.UnitsSet(units);
builder.JointAdd(new LinearJointMapping(0, CartesianAxis.X) { ExpectedLabel = xLabel, Scaling = scaling, Offset = offset });
builder.JointAdd(new LinearJointMapping(1, CartesianAxis.Y) { ExpectedLabel = yLabel, Scaling = scaling, Offset = offset });
builder.JointAdd(new LinearJointMapping(2, CartesianAxis.Z) { ExpectedLabel = zLabel, Scaling = scaling, Offset = offset });
builder.JointAdd(new LinearJointMapping(3, CartesianAxis.Roll) { ExpectedLabel = aLabel, Scaling = scaling, Offset = offset });
builder.JointAdd(new LinearJointMapping(4, CartesianAxis.Pitch) { ExpectedLabel = bLabel, Scaling = scaling, Offset = offset });
builder.JointAdd(new LinearJointMapping(5, CartesianAxis.Yaw) { ExpectedLabel = cLabel, Scaling = scaling, Offset = offset });
// create Robot object with multi axis and kinematic model
Robot robot = Robot.RobotCreate(controller, jointsMultiAxis, builder, MotionController.AxisFrameBufferSizeDefault);
// print some robot info
Console.WriteLine($"Robot model: {robot.ModelGet().NameGet()}");
Console.WriteLine($"Robot units: {robot.ModelGet().UnitsGet()}");
// set path motion parameters
robot.PathAccelerationSet(1000); // user units per sec squared
robot.PathVelocitySet(50); // user units per sec
// program path motion
robot.PathProgrammingModeSet(PathMode.Absolute);
robot.PathLine(target: new Pose(1, 1, 1));
robot.PathArc(
target: new Pose(0, 2, 1),
center: new Vector3d(0, 1, 1),
// enable amplifiers
jointsMultiAxis.AmpEnableSet(true);
// start path motion (non-blocking)
robot.Run();
// monitor motion
while (robot.IsRunning())
{
Thread.Sleep(100);
Console.WriteLine("Path motion executing...");
}
// cleanup
Robot.RobotDelete(controller, robot);
}
// handle errors as needed
finally
{
controller.Delete(); // dispose
}
static void ConfigurePhantomAxis(Axis phantomAxis)
Configures a phantom axis on the controller.
Definition _helpers.cs:144
static void CheckErrors(RapidCodeObject rsiObject)
Checks for errors in the given RapidCodeObject and throws an exception if any non-warning errors are ...
Definition _helpers.cs:15
Helpers class provides static methods for common tasks in RMP applications.
Definition _helpers.cs:5
void UserLabelSet(const char *const userLabel)
Set the axis User defined Label.
Represents a single axis of motion control. This class provides an interface for commanding motion,...
Definition rsi.h:5870
Axis * AxisGet(int32_t axisNumber)
AxisGet returns a pointer to an Axis object and initializes its internals.
static constexpr int32_t AxisFrameBufferSizeDefault
The default value of the AxisFrameBufferSize, also the minimum allowable value.
Definition rsi.h:854
static MotionController * Get()
Get an already running RMP EtherCAT controller.
void Delete(void)
Delete the MotionController and all its objects.
MultiAxis * MultiAxisGet(int32_t motionSupervisorNumber)
MultiAxisGet returns a pointer to a MultiAxis object and initializes its internals.
Represents the RMP soft motion controller. This class provides an interface to general controller con...
Definition rsi.h:800
void AxesAdd(Axis **axes, int32_t axisCount)
Represents multiple axes of motion control, allows you to map two or more Axis objects together for e...
Definition rsi.h:10804
void ClearFaults()
Clear all faults for an Axis or MultiAxis.
int32_t AmpEnableSet(bool enable, int32_t ampActiveTimeoutMilliseconds=AmpEnableTimeoutMillisecondsDefault, bool overrideRestrictedState=false)
Enable all amplifiers.
PathMode
Motion types. For G-code use and Cartesian path motion.
CartesianAxis
This enum specifies which Cartesian axis a LinearJointMapping maps a robot joint to.
RotationDirection
Rotational directions about an axis.


📜 Motion: Path Gantry

Learn how to set up a kinematic model with a gantry prime axis for Path Motion 📖 . Shows how to configure a 1:1 geared axis system where two physical axes work together.

/* This sample demonstrates how to set up a kinematic model with a gantry prime axis.
Shows how to configure a 1:1 geared axis system where two physical axes work together
to control the same cartesian coordinate.
*/
using RSI.RapidCode; // RSI.RapidCode.dotNET;
Console.WriteLine("📜 Motion: Path Gantry");
// get rmp objects
try
{
Helpers.CheckErrors(controller);
// set robot axis labels
const string xLabel = "X-Axis";
const string yLabel = "Y-Axis";
const string yPrimeLabel = "Y-Prime";
// get the 3 axis needed for XY_Yp robot
Axis xAxis = controller.AxisGet(Constants.AXIS_0_INDEX);
Axis yAxis = controller.AxisGet(Constants.AXIS_1_INDEX);
Axis primeAxis = controller.AxisGet(Constants.AXIS_2_INDEX);
Helpers.CheckErrors(primeAxis);
// configure phantom axes
// set the expected labels for each axis
xAxis.UserLabelSet(xLabel);
yAxis.UserLabelSet(yLabel);
primeAxis.UserLabelSet(yPrimeLabel);
// the joint index of each axis is the index within the MultiAxis object
// "X-Axis" has joint index 0
// "Y-Axis" has joint index 1
// "Y-Prime" has joint index 2
MultiAxis jointsMultiAxis = controller.MultiAxisGet(0);
Axis[] axes = [xAxis, yAxis, primeAxis];
jointsMultiAxis.AxesAdd(axes, axes.Length);
const LinearUnits units = LinearUnits.Millimeters;
const string modelName = "RSI_XY_Yp";
const double scaling = 1.0, offset = 0.0;
LinearModelBuilder builder = new(modelName);
builder.UnitsSet(units);
builder.JointAdd(new LinearJointMapping(0, CartesianAxis.X) { ExpectedLabel = xLabel, Scaling = scaling, Offset = offset });
builder.JointAdd(new LinearJointMapping(1, CartesianAxis.Y) { ExpectedLabel = yLabel, Scaling = scaling, Offset = offset });
builder.JointAdd(new LinearJointMapping(2, CartesianAxis.Y) { ExpectedLabel = yPrimeLabel, Scaling = scaling, Offset = offset });
// create Robot object where the y and y prime will be geared 1:1
const int motionFrameBufferSize = 50; // this is the minimum valid motion frame buffer size
Robot robot = Robot.RobotCreate(controller, jointsMultiAxis, builder, motionFrameBufferSize);
Console.WriteLine($"Model name: {robot.ModelGet().NameGet()}");
Console.WriteLine($"Model units: {robot.ModelGet().UnitsGet()}");
Console.WriteLine("Gantry configuration: Y-axis and Y-Prime axis are geared 1:1");
// cleanup
Robot.RobotDelete(controller, robot);
}
// handle errors as needed
finally
{
controller.Delete(); // dispose
}


📜 Motion: Path 3D Rendering

Learn how to get 3D path points for rendering visualization from Path Motion 📖 . Shows how to retrieve planned positions for use with 3D graphics libraries.

/* This sample demonstrates how to get 3D path points for rendering visualization.
Shows how to retrieve planned positions from a Robot path for use with 3D graphics libraries
or visualization tools.
*/
using RSI.RapidCode; // RSI.RapidCode.dotNET;
Console.WriteLine("📜 Motion: Path 3D Rendering");
// get rmp objects
try
{
Helpers.CheckErrors(controller);
// set robot axis labels
const string xLabel = "X-Axis";
const string yLabel = "Y-Axis";
const string zLabel = "Z-Axis";
// get the 3 axis needed for XYZ robot
Axis xAxis = controller.AxisGet(Constants.AXIS_0_INDEX);
Axis yAxis = controller.AxisGet(Constants.AXIS_1_INDEX);
Axis zAxis = controller.AxisGet(Constants.AXIS_2_INDEX);
// configure phantom axes
// set axis labels
xAxis.UserLabelSet(xLabel);
yAxis.UserLabelSet(yLabel);
zAxis.UserLabelSet(zLabel);
// create multi-axis object for joints
MultiAxis jointsMultiAxis = controller.MultiAxisGet(0);
Axis[] axes = [xAxis, yAxis, zAxis];
jointsMultiAxis.AxesAdd(axes, axes.Length);
// create simple 3-axis kinematic model
const string modelName = "RSI_XYZ";
const double scaling = 1.0;
const double offset = 0.0;
LinearModelBuilder builder = new(modelName);
builder.UnitsSet(LinearUnits.Millimeters);
builder.JointAdd(new LinearJointMapping(0, CartesianAxis.X) { ExpectedLabel = xLabel, Scaling = scaling, Offset = offset });
builder.JointAdd(new LinearJointMapping(1, CartesianAxis.Y) { ExpectedLabel = yLabel, Scaling = scaling, Offset = offset });
builder.JointAdd(new LinearJointMapping(2, CartesianAxis.Z) { ExpectedLabel = zLabel, Scaling = scaling, Offset = offset });
// create Robot object
Robot robot = Robot.RobotCreate(controller, jointsMultiAxis, builder, MotionController.AxisFrameBufferSizeDefault);
// set path motion parameters
robot.PathAccelerationSet(100);
robot.PathVelocitySet(50);
// program path motion
robot.PathProgrammingModeSet(PathMode.Absolute);
robot.PathLine(target: new Pose(1, 1, 1));
robot.PathArc(
target: new Pose(0, 2, 1),
center: new Vector3d(0, 1, 1),
// process the path to build trajectory
robot.PathProcessLoadedMoves();
// get path points for 3D rendering
Console.WriteLine("Retrieving 3D path points for rendering:");
const ulong frameCount = 500;
ulong startFrame = 0;
int totalPointCount = 0;
ulong retrievedFrames;
do
{
RapidVectorRobotPosition positions = robot.PathPlannedPositionsGet(startFrame, frameCount);
retrievedFrames = positions.Size();
foreach (RobotPosition position in positions.ToArray())
{
Vector3d spatial = position.Pose.Position;
// print first 4 points as example
if (totalPointCount < 4)
{
Console.WriteLine($"Point {totalPointCount}: X={spatial.X:F2}, Y={spatial.Y:F2}, Z={spatial.Z:F2}");
}
totalPointCount++;
// add code here to create rendering with your preferred 3D library
// examples:
// vector3 = new Vector3D(spatial.X, spatial.Y, spatial.Z);
// linePositions.Add(vector3);
// scene.AddPoint(spatial.X, spatial.Y, spatial.Z);
}
startFrame += retrievedFrames;
}
while (retrievedFrames == frameCount);
// print total points retrieved
Console.WriteLine($"Total 3D points retrieved: {totalPointCount}");
// cleanup
Robot.RobotDelete(controller, robot);
}
// handle errors as needed
finally
{
controller.Delete(); // dispose
}