SingleJointedArmSim

class wpilib.simulation.SingleJointedArmSim(*args, **kwargs)

Bases: LinearSystemSim_2_1_1

Represents a simulated arm mechanism.

Overloaded function.

  1. __init__(self: wpilib.simulation._simulation.SingleJointedArmSim, system: wpimath._controls._controls.system.LinearSystem_2_1_1, gearbox: wpimath._controls._controls.plant.DCMotor, gearing: float, armLength: wpimath.units.meters, minAngle: wpimath.units.radians, maxAngle: wpimath.units.radians, simulateGravity: bool, startingAngle: wpimath.units.radians, measurementStdDevs: Annotated[list[float], FixedSize(1)] = [0.0]) -> None

Creates a simulated arm mechanism.

Parameters:

  • system – The system representing this arm. This system can be created with LinearSystemId::SingleJointedArmSystem().

  • gearbox – The type and number of motors on the arm gearbox.

  • gearing – The gear ratio of the arm (numbers greater than 1 represent reductions).

  • armLength – The length of the arm.

  • minAngle – The minimum angle that the arm is capable of.

  • maxAngle – The maximum angle that the arm is capable of.

  • simulateGravity – Whether gravity should be simulated or not.

  • startingAngle – The initial position of the arm.

  • measurementStdDevs – The standard deviations of the measurements.

  1. __init__(self: wpilib.simulation._simulation.SingleJointedArmSim, gearbox: wpimath._controls._controls.plant.DCMotor, gearing: float, moi: wpimath.units.kilogram_square_meters, armLength: wpimath.units.meters, minAngle: wpimath.units.radians, maxAngle: wpimath.units.radians, simulateGravity: bool, startingAngle: wpimath.units.radians, measurementStdDevs: Annotated[list[float], FixedSize(1)] = [0.0]) -> None

Creates a simulated arm mechanism.

Parameters:

  • gearbox – The type and number of motors on the arm gearbox.

  • gearing – The gear ratio of the arm (numbers greater than 1 represent reductions).

  • moi – The moment of inertia of the arm. This can be calculated from CAD software.

  • armLength – The length of the arm.

  • minAngle – The minimum angle that the arm is capable of.

  • maxAngle – The maximum angle that the arm is capable of.

  • simulateGravity – Whether gravity should be simulated or not.

  • startingAngle – The initial position of the arm.

  • measurementStdDevs – The standard deviation of the measurement noise.

static estimateMOI(length: wpimath.units.meters, mass: wpimath.units.kilograms) → wpimath.units.kilogram_square_meters

Calculates a rough estimate of the moment of inertia of an arm given its length and mass.

Parameters:

  • length – The length of the arm.

  • mass – The mass of the arm.

Returns:

The calculated moment of inertia.

getAngle() → wpimath.units.radians

Returns the current arm angle.

Returns:

The current arm angle.

getAngleDegrees() → wpimath.units.degrees
getCurrentDraw() → wpimath.units.amperes

Returns the arm current draw.

Returns:

The arm current draw.

getVelocity() → wpimath.units.radians_per_second

Returns the current arm velocity.

Returns:

The current arm velocity.

getVelocityDps() → wpimath.units.degrees_per_second
hasHitLowerLimit() → bool

Returns whether the arm has hit the lower limit.

Returns:

Whether the arm has hit the lower limit.

hasHitUpperLimit() → bool

Returns whether the arm has hit the upper limit.

Returns:

Whether the arm has hit the upper limit.

setInputVoltage(voltage: wpimath.units.volts) → None

Sets the input voltage for the arm.

Parameters:

voltage – The input voltage.

setState(angle: wpimath.units.radians, velocity: wpimath.units.radians_per_second) → None

Sets the arm’s state. The new angle will be limited between the minimum and maximum allowed limits.

Parameters:

  • angle – The new angle.

  • velocity – The new angular velocity.

wouldHitLowerLimit(armAngle: wpimath.units.radians) → bool

Returns whether the arm would hit the lower limit.

Parameters:

armAngle – The arm height.

Returns:

Whether the arm would hit the lower limit.

wouldHitUpperLimit(armAngle: wpimath.units.radians) → bool

Returns whether the arm would hit the upper limit.

Parameters:

armAngle – The arm height.

Returns:

Whether the arm would hit the upper limit.