#include <CANVenom.h>

Inheritance diagram for frc::CANVenom:

Public Types
enum	ControlMode { kDisabled = 0, kProportional = 1, kCurrentControl = 3, kSpeedControl = 4, kPositionControl = 5, kMotionProfile = 6, kFollowTheLeader = 7, kVoltageControl = 8 }

enum	BrakeCoastMode { kCoast = 0, kBrake = 1 }

enum	FaultFlag { kNone = 0, kNoHeartbeat = 1, kNoLeaderHeartbeat = 2, kBadLeaderID = 4, kHighTemperature = 8, kHighCurrent = 16, kBadMode = 32, kDuplicateID = 64, kForwardLimit = 128, kReverseLimit = 256, kReset = 512 }

enum	MotionProfileState { kInit = 0, kRunning = 1, kErrBufferCleared = 2, kErrBufferUnderflow = 3, kErrBufferInvalid = 4, kDone = 5 }

Public Member Functions
	CANVenom (uint8_t motorID)

virtual	~CANVenom ()

	CANVenom (const CANVenom &)=delete

CANVenom &	operator= (const CANVenom &)=delete

	CANVenom (CANVenom &&)=default

CANVenom &	operator= (CANVenom &&)=default

virtual void	StopMotor () override

virtual void	GetDescription (wpi::raw_ostream &desc) const override

virtual void	Set (double command) override

virtual double	Get () const override

virtual void	SetInverted (bool isInverted) override

virtual bool	GetInverted () const override

virtual void	Disable () override

void	Enable ()

virtual void	PIDWrite (double output) override

virtual void	InitSendable (SendableBuilder &builder)

void	SetCommand (ControlMode mode, double command)

void	SetCommand (ControlMode mode, double command, double kF, double b)

void	Follow (CANVenom &leadVenom)

bool	GetFwdLimitSwitchActive () const

bool	GetRevLimitSwitchActive () const

void	EnableLimitSwitches (bool fwdLimitSwitchEnabled, bool revLimitSwitchEnabled)

void	IdentifyMotor ()

void	ResetPosition ()

void	SetPosition (double newPosition)

uint16_t	GetNumAvaliableMotionProfilePoints () const

uint16_t	GetCurrentMotionProfilePoint () const

double	GetMotionProfilePositionTarget () const

double	GetMotionProfileSpeedTarget () const

bool	GetMotionProfileIsValid () const

MotionProfileState	GetMotionProfileState () const

void	ClearMotionProfilePoints ()

void	AddMotionProfilePoint (double time, double speed, double position)

void	CompleteMotionProfilePath (double time, double position)

void	ExecutePath ()

uint32_t	GetFirmwareVersion () const

uint32_t	GetSerialNumber () const

double	GetBusVoltage () const

double	GetOutputVoltage () const

double	GetDutyCycle () const

double	GetOutputCurrent () const

double	GetTemperature () const

double	GetAuxVoltage () const

double	GetSpeed () const

double	GetPosition () const

double	GetPIDTarget () const

double	GetKF () const

double	GetB () const

double	GetKP () const

double	GetKI () const

double	GetKD () const

double	GetMinPILimit () const

double	GetMaxPILimit () const

double	GetMaxSpeed () const

double	GetMaxAcceleration () const

double	GetMaxJerk () const

ControlMode	GetControlMode () const

ControlMode	GetActiveControlMode () const

BrakeCoastMode	GetBrakeCoastMode () const

FaultFlag	GetActiveFaults () const

FaultFlag	GetLatchedFaults () const

void	ClearLatchedFaults ()

void	SetPID (double kP, double kI, double kD, double kF, double b)

void	SetKF (double kF)

void	SetB (double b)

void	SetKP (double kP)

void	SetKI (double kI)

void	SetKD (double kD)

void	SetMinPILimit (double limit)

void	SetMaxPILimit (double limit)

void	SetMaxSpeed (double limit)

void	SetMaxAcceleration (double limit)

void	SetMaxJerk (double limit)

void	SetControlMode (ControlMode controlMode)

void	SetBrakeCoastMode (BrakeCoastMode brakeCoastMode)

Detailed Description

CAN based Venom motor controller instance

This class is used to control a single Venom motor connected to the roboRIO through the CAN bus. The motor supports many controls modes, including: Proportional Dutycycle, Voltage compensated proportional, closed-loop current, closed-loop speed with true s-curve trajector planning, closed-loop position control and motion profile execution

Member Enumeration Documentation

◆ BrakeCoastMode

enum frc::CANVenom::BrakeCoastMode

Enumerator
kCoast	The motor is open circuited when the porportional or volatage command is zero, causing the motor to coast or free-wheel
kBrake	The motor is shorted when the porportional or vlotage command is zero. This acts to brake/slow the motor to a stop.

◆ ControlMode

enum frc::CANVenom::ControlMode

Enumerator
kDisabled	Motor is disabled and coasting
kProportional	Proportional (duty-cycle) control
kCurrentControl	Closed-loop current (torque) control
kSpeedControl	Closed-loop speed control.
kPositionControl	Closed-loop position (servo) control.
kMotionProfile	Execute a motion control path. Motion profiles are generally loaded in Disabled mode. The transition to the MotionProfile state causes Venom to begin following the path.
kFollowTheLeader	Follow the duty cycle commanded to another Venom motor. Generally used when more that one Venom is geared together in a drivetrain application. In that case one Venom, the leader, executes a motion profile or is placed in another control mode. The other Venom(s) are placed in FolloewTheLeader and command the same duty cycle as the leader so that only the leader is used to calculate closed-loop commands. This avoid implementing PID controllers on multiple motors which may "fight".
kVoltageControl	Open-loop voltage control mode, also refered to voltage compensated proportional mode

◆ FaultFlag

enum frc::CANVenom::FaultFlag

Enumerator
kNone	No Active Faults
kNoHeartbeat	Missing heartbeat from the roboRIO. Ensure device ID matches device ID used by CANVenom class.
kNoLeaderHeartbeat	Lead motor heartbeat is missing while in FollowTheLeader mode.
kBadLeaderID	The lead motor ID is same as the motor ID. One Venom cannot follow itself. Ensure the leader and follower have different IDs
kHighTemperature	Motor temperature is too high
kHighCurrent	Average motor current is too high
kBadMode	An invalid control mode was specified by the roboRIO. This should not occur when using PlayingWithFusionDriver. Contact PWF Technical support.
kDuplicateID	Another Venom with the same device ID was detected on the CAN bus. All Venom device IDs must be unique
kForwardLimit	The forward limit switch is enabled and is active
kReverseLimit	The reverse limit switch is enabled and is active
kReset	The Venom motor reset, lost power, or browned out since the last time the ClearLatchedFaults function was called

◆ MotionProfileState

enum frc::CANVenom::MotionProfileState

Enumerator
kInit	Initial state after Venom powerup
kRunning	Motion profile is currently executing, but has not reached the final point yet. No errors are active
kErrBufferCleared	The motion profile buffer was cleared while the profile was being executed. The motor cannot continue and will coast until the motor is placed in another control mode (to reset the error condition)
kErrBufferUnderflow	The motor ran out of points while executing a motion profile. Either new points were not sent to the motor fast enough or the profile wasn't terminated using the CompleteMotionProfilePath function. The motor cannot continue and will coast until the motor is placed in another control mode (to reset the error condition)
kErrBufferInvalid	Attempted to begin executing a motion profile but there was no valid start point. This can happen if the ClearMotionProfilePoints function is not called before loading a motion profile, or if too many points are loaded and the motor cannot buffer the entire path. Venom can buffer about 300 points. The exact buffer length can be be determined by calling GetNumAvaliableMotionProfilePoints immediatly after power up. If the motion profile contains more points than can be stored in the buffer, the profile must be reloaded each time before begining to follow the profile. For large paths with many points, first load a subset of the points, begin executing the path, then continue to load new points as the motor executes the path. Call the GetNumAvaliableMotionProfilePoints function periodically to ensure the Venom buffer has sufficient space before loading additional points.
kDone	The motion profile was successfully executed. The motor will now hold the current position (at zero speed) until the motor is placed in another control mode.

Constructor & Destructor Documentation

◆ CANVenom()

CANVenom::CANVenom ( uint8_t motorID )

explicit

Create an instance of the CAN Venom Motor Controller driver.

This is designed to support the Playing With Fusion Venom motor controller

Parameters

motorId The 6-bit identifier used to select a particular motor on the CAN bus. This identifier may be set through the PWF Device configuration page on the roboRIO.

◆ ~CANVenom()

CANVenom::~CANVenom ( )

virtual

Destroy the CANVenom object and free any asscioated resources.

Member Function Documentation

◆ AddMotionProfilePoint()

void CANVenom::AddMotionProfilePoint	(	double	time,
		double	speed,
		double	position
	)

Add single motion profile point.

Add a single point to the motion profile buffer. To load a motion profile, the application should call clearMotionProfilePoints(), then call addMotionProfilePoint() for each point. The application should then close the path using completeMotionProfilePath() Once a path is loaded, or partially loaded, the application may initiate the motion profile using executePath() or setCommand(ControlMode.MotionProfile, 0)

The motor will will lineraly interpolate commanded speed and position between motion profile points. Acceleration and Jerk limits are not used when executing a motion profile

Parameters

time	Time since the start of the profile in miliseconds
speed	Commanded speed in rotations per second
position	Commanded motor angle/position in revolutions

◆ ClearLatchedFaults()

void CANVenom::ClearLatchedFaults ( )

Clear all latched faults

◆ ClearMotionProfilePoints()

void CANVenom::ClearMotionProfilePoints ( )

Erase all motion profile points.

Clear all motion profile points from the motor controller buffer. This function should Be called first, each time a new motion profile path is loaded into the motor controller.

◆ CompleteMotionProfilePath()

void CANVenom::CompleteMotionProfilePath	(	double	time,
		double	position
	)

Add final point to motion profile.

Add the last point to a motion profile. The motor will attempt to hold the commanded poistion indefinitly once reaching the final point.

Parameters

time	Time since the start of the profile in milliseconds
position	Commanded motor angle/position in revolution

◆ Disable()

void CANVenom::Disable ( )

overridevirtual

Stop applying power to the motor immediately.

If Brake mode is active and the current control mode is Proportional or VoltageControl the motor will brake to a stop. Otherwise the motor will coast.

The enable() function must be called after a call to stopMotor() before motion may be commanded again.

◆ Enable()

void CANVenom::Enable ( )

Enable the motor again after a call to stopMotor() or disable().

◆ EnableLimitSwitches()

void CANVenom::EnableLimitSwitches	(	bool	fwdLimitSwitchEnabled,
		bool	revLimitSwitchEnabled
	)

Enable/disable the forward and reverse limit switches.

Parameters

fwdLimitSwitchEnabled	Prevent forward rotation if this argument is true and the forward limit switch is active
revLimitSwitchEnabled	Prevent reverse rotation if this argument is true and the forward limit switch is active

◆ ExecutePath()

void CANVenom::ExecutePath ( )

Execute stored motion profile.

Instruct the motor to begin following the sotred motion profile. This function is equivlelent to calling setCommand(ControlMode.MotionProfile, 0)

◆ Follow()

void CANVenom::Follow ( CANVenom & leadVenom )

Place the motor into FollowTheLeader mode and follow the specified motor

This method is equivelent to calling SetComand(FollowTheLeader, ID_of_lead_motor);

Parameters

leadVenom Reference to the CANVenom instance which reperesents the lead motor.

◆ Get()

double CANVenom::Get ( ) const

overridevirtual

Get the motor duty-cycle.

Returns: The motor duty cycle as a ratio between -1.0 and 1.0.

◆ GetActiveControlMode()

CANVenom::ControlMode CANVenom::GetActiveControlMode ( ) const

Get the active Venom control mode.

Returns: Get the active Venom control mode reported by the motor.

◆ GetActiveFaults()

CANVenom::FaultFlag CANVenom::GetActiveFaults ( ) const

Return set of active motor faults which curently limit or disable motor output. More than one Fault may be active at a time

Returns: Bitmask of active faults

◆ GetAuxVoltage()

double CANVenom::GetAuxVoltage ( ) const

Get the measured voltage at the auxilary analog input on the limit switch breakout board.

Returns: Auxilary analog input voltage in Volts.

◆ GetB()

double CANVenom::GetB ( ) const

Get the feed-forward command offset in SpeedControl, PositionControl, CurrentCurrent and MotionProfile control modes.

Returns: Feed-forward offset as duty-cycle between -2.0 and 2.0.

◆ GetBrakeCoastMode()

CANVenom::BrakeCoastMode CANVenom::GetBrakeCoastMode ( ) const

Get the brake/coast behavior when zero is commanded in Proportional and VoltageControl control modes.

Returns: The Brake or Coast behavion in Proportional and VoltageControl modes

◆ GetBusVoltage()

double CANVenom::GetBusVoltage ( ) const

Get the bus (battery) voltage supplying the Venmom motor.

Returns: The bus voltage in Volts

◆ GetControlMode()

CANVenom::ControlMode CANVenom::GetControlMode ( ) const

Get the commanded Venom control mode.

Returns: The commanded control mode

◆ GetCurrentMotionProfilePoint()

uint16_t CANVenom::GetCurrentMotionProfilePoint ( ) const

Get current motion profile point

Gets the active motion profile point while a motion profile is active. The first point sent to the controller acter a call to clearMotionProfilePoints() is point 0. The next point is 1, then 2, and so on.

Returns: The motion profile point which is currently targeted by the Venom controller

◆ GetDescription()

void CANVenom::GetDescription ( wpi::raw_ostream & desc ) const

overridevirtual

Return a description of this motor controller.

Returns: The Venom motor controller description

◆ GetDutyCycle()

double CANVenom::GetDutyCycle ( ) const

Get the motor h-bridge duty cycle.

Returns: The motor duty cycle as a ration between -1.0 and 1.0

◆ GetFirmwareVersion()

uint32_t CANVenom::GetFirmwareVersion ( ) const

Return the Venom motor firmware version of the motor asscioated with this instance of the CANVenom class.

Returns: The Venom motor firmware version (multiplied by 100)

◆ GetFwdLimitSwitchActive()

bool CANVenom::GetFwdLimitSwitchActive ( ) const

Determine the state of the forward motion limit switch.

An internal pull-up resistor activates the limit switch is nothing is connected. Connect the limit switch to GND to deactivate the limit.

Returns: true if the limit switch voltage is high (which would prevent forward rotation if the limit was enabled)

◆ GetInverted()

bool CANVenom::GetInverted ( ) const

overridevirtual

Return the motor direction inversion state.

Returns: True if the motor direction is inverted

◆ GetKD()

double CANVenom::GetKD ( ) const

Get the close-loop PID derative gain in SpeedControl, PositionControl, CurrentCurrent and MotionProfile control modes.

Returns: PID derivative gain as ratio between 0.0 and 4.0.

◆ GetKF()

double CANVenom::GetKF ( ) const

Get the feed-forward gain in SpeedControl, PositionControl, CurrentCurrent and MotionProfile control modes.

Returns: Feed-forward gain as ratio between -8.0 and 8.0.

◆ GetKI()

double CANVenom::GetKI ( ) const

Get the close-loop PID integral gain in SpeedControl, PositionControl, CurrentCurrent and MotionProfile control modes.

Returns: PID integral gain as ratio between 0.0 and 4.0.

◆ GetKP()

double CANVenom::GetKP ( ) const

Get the close-loop PID proportional gain in SpeedControl, PositionControl, CurrentCurrent and MotionProfile control modes.

Returns: PID proportional gain as ratio between 0.0 and 4.0.

◆ GetLatchedFaults()

CANVenom::FaultFlag CANVenom::GetLatchedFaults ( ) const

Return set of latched motor faults which are curently active or were previously active since the last time the ClearLatchedFaults function was called. This function can be helpful when diagnosing harness or brownout issues which cause Venom to reset. The Reset flag will be set each time venom starts up.

Returns: Bitmask of latched faults

◆ GetMaxAcceleration()

double CANVenom::GetMaxAcceleration ( ) const

Get the maximum acceleration in the SpeedControl and PositionControl control modes.

This number is used as part of the s-curve path planning in SpeedControl mode and the trapezoid planning in Position Control mode.

Trajectory planning is disabled if the maximum accelleration is zero.

Returns: Maximum acceleration RPM per second

◆ GetMaxJerk()

double CANVenom::GetMaxJerk ( ) const

Get the maximum jerk (second derivitive of speed) in the SpeedControl control mode.

This number is used as part of the s-curve path planning.

The jerk limit is disabled if the maximum jerk is 0..

Returns: Maximum jerk RPM per second squared

◆ GetMaxPILimit()

double CANVenom::GetMaxPILimit ( ) const

Get the maximum duty cycle that may be commanded by the PID in SpeedControl, PositionControl, CurrentCurrent and MotionProfile control modes.

Returns: Maximum PID output duty-cycle as a ratio between -1.0 and 1.0.

◆ GetMaxSpeed()

double CANVenom::GetMaxSpeed ( ) const

Get the maximum speed (absolute value of velocity) that may be commanded in the SpeedControl and PositionControl control modes.

Returns: Maximum speed command in RPM.

◆ GetMinPILimit()

double CANVenom::GetMinPILimit ( ) const

Get the minimum duty cycle that may be commanded by the PID in SpeedControl, PositionControl, CurrentCurrent and MotionProfile control modes.

Returns: Minimum PID output duty-cycle as a ratio between -1.0 and 1.0.

◆ GetMotionProfileIsValid()

bool CANVenom::GetMotionProfileIsValid ( ) const

Determine if the motor is prepared to execute a motion profile

Determins is a valit start point is present and that the motor is read to begin executing a motion profile.

Returns: True if the motion profile stored on the motor contains a valid start point

◆ GetMotionProfilePositionTarget()

double CANVenom::GetMotionProfilePositionTarget ( ) const

Get the instantaneous motion profile position commanded

Gets the motor position commanded by the current motion profile point while a motion profile is active

Returns: The commanded motor position in revolutions.

◆ GetMotionProfileSpeedTarget()

double CANVenom::GetMotionProfileSpeedTarget ( ) const

Get the instantaneous motion profile speed commanded

Gets the motor speed commanded by the current motion profile point while a motion profile is active

Returns: The commanded speed position in revolutions per second (not RPM).

◆ GetMotionProfileState()

CANVenom::MotionProfileState CANVenom::GetMotionProfileState ( ) const

Get the Motion Profile state.

Gets the state of the internal Venom Motion Profile state machine. This state can be used to determine if a motion profile is being executed, has completed sucessfully, or has stopped due to an error.

Returns: Venom Motion Profile state.

◆ GetNumAvaliableMotionProfilePoints()

uint16_t CANVenom::GetNumAvaliableMotionProfilePoints ( ) const

Get number of empty motion profile points avaliable.

Gets number of motion profile point buffer locations avaliable in motor controller. The motor will ignore additional calls to addMotionProfilePoint() once all buffer locations are full.

Returns: The number of remaining empty motion profile points which may be loaded into the Venom controller

◆ GetOutputCurrent()

double CANVenom::GetOutputCurrent ( ) const

Get the measured motor current consumption.

Current is measured between the Venom power leads (the battery) to the motor brushes. Current is positive regardles of motor direction. Only current from the battery to the motor is measured. Zero amps are returned if the motor is charging the battery.

Returns: The measured current Amps.

◆ GetOutputVoltage()

double CANVenom::GetOutputVoltage ( ) const

Get the calculated voltage across the motor burshes.

Returns: The calculated motor voltage in Volts.

◆ GetPIDTarget()

double CANVenom::GetPIDTarget ( ) const

Internal PID Target (position, speed, current).

The PID target is equal to the motor command specified by setCommand() in CurrentControl mode. In SpeedControl and PositionControl modes, the PID command is the output of the s-curve or trapezoidal slew rate limit calculation. In MotionProfile mode the PID command is equal to the current motion profile position command.

In all closed-loop modes, the PID target represents the motor speed/position/current that the Venom PID is activly trying to achieve

Returns: PID target in RPM, rotations, or Amps (based on current control mode)

◆ GetPosition()

double CANVenom::GetPosition ( ) const

Signed motor revolutions (position) since the last time it was cleared.

Returns: The signed motor position in revolutions.

◆ GetRevLimitSwitchActive()

bool CANVenom::GetRevLimitSwitchActive ( ) const

Determine the state of the reverse motion limit switch.

And internal pull-up resistor activates the limit switch is nothing is connected. Connect the limit switch to GND to deactivate the limit.

Returns: true if the limit switch voltage is high (which would prevent reverse rotation if the limit was enabled)

◆ GetSerialNumber()

uint32_t CANVenom::GetSerialNumber ( ) const

Return the serial number of the motor asscioated with this instance of the CANVenom class.

Returns: The Venom motor serial number

◆ GetSpeed()

double CANVenom::GetSpeed ( ) const

Measured signed motor velocity in RPM.

Returns: Motor velocity in RPM.

◆ GetTemperature()

double CANVenom::GetTemperature ( ) const

The measured Venom backplate temperature.

Returns: Measured backplate temperature in degrees C.

◆ IdentifyMotor()

void CANVenom::IdentifyMotor ( )

Flash LED to identify motor.

Identify the physical motor asscioated with this instance of the Venom driver by causing its LED to flash red and green for several seconds.

◆ InitSendable()

void CANVenom::InitSendable ( SendableBuilder & builder )

virtual

Initialize vaiiables and parameters to be passed into the smart dashboard.

◆ PIDWrite()

void CANVenom::PIDWrite ( double output )

overridevirtual

Used by an instance of PIDController to command the motor duty-cycle

Places the motor in Proportional control mode and sets the motor proportional command. If disable() or stopMotor() is called, enable() must be called before set() will command motion again.

Parameters

speed Proportional motor command from -1.0 to 1.0

◆ ResetPosition()

void CANVenom::ResetPosition ( )

Reset the motor revolution counter (position) to 0.

◆ Set()

void CANVenom::Set ( double command )

overridevirtual

Sets the motor duty-cycle command.

Places the motor in Proportional control mode and sets the motor proportional command. If disable() or stopMotor() is called, enable() must be called before set() will command motion again.

Parameters

speed Proportional motor duty-cycle command from -1.0 to 1.0

◆ SetB()

void CANVenom::SetB ( double b )

Set Feed-forward duty cycle offset in closed loop control modes.

Parameters

b	Feed-forward offset as duty-cycle between -2.0 and 2.0.

◆ SetBrakeCoastMode()

void CANVenom::SetBrakeCoastMode ( CANVenom::BrakeCoastMode brakeCoastMode )

Set the brake/coast behavior when zero is commanded in Proportional and VoltageControl control modes.

Parameters

brakeCoastMode The Brake or Coast behavior in Proportional and VoltageControl modes.

◆ SetCommand() [1/2]

void CANVenom::SetCommand	(	ControlMode	mode,
		double	command
	)

Set the motor command and control mode.

Where control mode is one of:

Proportional - command specifies the raw motor duty-cycle as a ratio between -1.0 and 1.0
CurrentControl - command specifies a target motor current in Amps between -40.0 and 40.0.
- Note that the commanded is signed to specify the motor direction, but the measured motor current provided by the getOutputCurrent() function is unsigned (the absolute value of current)
- In this mode a PID active controls the motor duty cycle to achieve the commanded current.
VoltageControl - command specified the voltage to be applied to the motor bushes as a value between 0.0 and 14.0 Volts.
- This mode is also refered to as voltage compensated proportional mode.
- Is is useful because the motor speed at a given voltage voltage will be constant if the battery voltage changes, as long as the voltage command is less than the battery voltage.
SpeedControl - command specifies the motor speed value between -6000.0 and 6000.0 RPM.
- In this mode a PID activle controls the motor duty cycle to achieve the commanded speed
PositionControl - command specifies the motor position as a value between -4096 and 4096 motor revolutions.
- This mode is sometime refered to as servo control because the motor attempts to hold a commanded position, just like a servo.
- In this mode a PID actively controls motor duty cycle to achieve the commanded position
MotionProfile - command is unused.
- The motor attempts to follow a previously entered motion profile.
- Once the last point in the motion profile is reached the motor will hold the last command position from the profile.
- See the addMotionProfilePoint() function for more details
FollowTheLeader - command specified the device ID of the Venom motor to follow.
- In this mode the Venom motor will command the same duty cycle as the lead motor.
- Generally used when more that one Venom is geared together in a drivetrain application. In that case one Venom, the leader, executes a motion profile or is placed in another control mode. The other Venom(s) are placed in FolloewTheLeader and command the same duty cycle as the leader so that only the leader is used to calculate closed-loop commands. This avoid implementing PID controllers on multiple motors which may "fight".

Parameters

mode	Motor control mode (Proportional, CurrentControl, SpeedControl, etc.)
command	Motor command (%, Amps, RPM, etc)

◆ SetCommand() [2/2]

void CANVenom::SetCommand	(	ControlMode	mode,
		double	command,
		double	kF,
		double	b
	)

Set the motor command and control mode.

Where control mode is one of:

Proportional - command specifies the raw motor duty-cycle as a ratio between -1.0 and 1.0
CurrentControl - command specifies a target motor current in Amps between -40.0 and 40.0.
- Note that the commanded is signed to specify the motor direction, but the measured motor current provided by the getOutputCurrent() function is unsigned (the absolute value of current)
- In this mode a PID active controls the motor duty cycle to achieve the commanded current.
VoltageControl - command specified the voltage to be applied to the motor bushes as a value between 0.0 and 14.0 Volts.
- This mode is also refered to as voltage compensated proportional mode.
- Is is useful because the motor speed at a given voltage voltage will be constant if the battery voltage changes, as long as the voltage command is less than the battery voltage.
SpeedControl - command specifies the motor speed value between -6000.0 and 6000.0 RPM.
- In this mode a PID activle controls the motor duty cycle to achieve the commanded speed
PositionControl - command specifies the motor position as a value between -4096 and 4096 motor revolutions.
- This mode is sometime refered to as servo control because the motor attempts to hold a commanded position, just like a servo.
- In this mode a PID actively controls motor duty cycle to achieve the commanded position
MotionProfile - command is unused.
- The motor attempts to follow a previously entered motion profile.
- Once the last point in the motion profile is reached the motor will hold the last command position from the profile.
- See the AddMotionProfilePoint function for more details
FollowTheLeader - command specified the device ID of the Venom motor to follow.
- In this mode the Venom motor will command the same duty cycle as the lead motor.
- Generally used when more that one Venom is geared together in a drivetrain application. In that case one Venom, the leader, executes a motion profile or is placed in another control mode. The other Venom(s) are placed in FolloewTheLeader and command the same duty cycle as the leader so that only the leader is used to calculate closed-loop commands. This avoid implementing PID controllers on multiple motors which may "fight".

When the kF and b terms are included in this function, they are guarenteed to be sent to the motor in the same CAN frame as the control mode and command. This is useful when an open-loop correction or feed-forward term is calculated by the roboRIO.

Parameters

mode	Motor control mode (Proportional, CurrentControl, SpeedControl, etc.)
command	Motor command (%, Amps, RPM, etc)
kF	Feed-forward gain as ratio between -8.0 and 8.0
b	Feed-forward offset as duty-cycle between -2.0 and 2.0

◆ SetControlMode()

void CANVenom::SetControlMode ( CANVenom::ControlMode controlMode )

Set the Venom motor control mode.

Set the control mode without modifying the motor command.

The prefered method to change the motor control mode is the setCommand function. Using setCommand() guarentees the control mode and the motor command will be received by the Venom controller at the same time.

Parameters

controlMode The commanded control mode.

◆ SetInverted()

void CANVenom::SetInverted ( bool isInverted )

overridevirtual

Specify which direction the motor rotates in response to a posive motor command.

When inverted the motor will spin the opposite direction it rotates when isInverted is false. The motor will always report a positive speed when commanded in the 'forward' direction.

This function is commonly used for drivetrain applications so that the and right motors both drive the frobot forward when given a forward command, even though one side is spinnig clockwise and the other is spinning counter clockwise.

Parameters

isInverted True if the motor direction should be reversed

◆ SetKD()

void CANVenom::SetKD ( double kD )

Set PID Derivative gain.

Parameters

kD	Derivative gain as a ratio between 0.0 and 4.0.

◆ SetKF()

void CANVenom::SetKF ( double kF )

Set Feed-forward gain in closed loop control modes.

Parameters

kF	Feed-forward gain as a ratio between -2.0 and 2.0

◆ SetKI()

void CANVenom::SetKI ( double kI )

Set PID Integral gain.

Parameters

kI	Integral gain as a ratio between 0.0 and 4.0.

◆ SetKP()

void CANVenom::SetKP ( double kP )

Set PID Proportional gain.

Parameters

kP	Proportional gain as a ratio between 0.0 and 4.0.

◆ SetMaxAcceleration()

void CANVenom::SetMaxAcceleration ( double limit )

Set the maximum acceleration in the SpeedControl and PositionControl control modes.

This number is used as part of the s-curve path planning in SpeedControl mode and the trapezoid planning in Position Control mode.

Trajectory planning is disabled if the maximum acceleration is zero

Parameters

limit Maximum acceleration between 0 and 25,500 RPM per second

◆ SetMaxJerk()

void CANVenom::SetMaxJerk ( double limit )

Set the maximum jerk (second derivitive of speed) in the SpeedControl control mode.

This number is used as part of the s-curve path planning.

The jerk limit is disabled if the maximum jerk is 0

Parameters

limit Maximum jerk between 0 and 159,375 RPM per second squared.

◆ SetMaxPILimit()

void CANVenom::SetMaxPILimit ( double limit )

Set the maximum duty cycle that may be commanded by the PID in SpeedControl, PositionControl, CurrentCurrent and MotionProfile control modes.

Parameters

limit Maximum PID output duty-cycle as a ratio between -1.0 and 1.0.

◆ SetMaxSpeed()

void CANVenom::SetMaxSpeed ( double limit )

Set the maximum speed (absolute value of velocity) that may be commanded in the SpeedControl and PositionControl control modes.

Parameters

limit Maximum speed command between 0 and 6000 RPM.

◆ SetMinPILimit()

void CANVenom::SetMinPILimit ( double limit )

Set the minimum duty cycle that may be commanded by the PID in SpeedControl, PositionControl, CurrentCurrent and MotionProfile control modes.

Parameters

limit Minimum PID output duty-cycle as a ratio between -1.0 and 1.0.

◆ SetPID()

void CANVenom::SetPID	(	double	kP,
		double	kI,
		double	kD,
		double	kF,
		double	b
	)

Set the PID gains for closed-loop control modes.

Sets the proportional, integral, and derivative gains as well as the feed-forward gain and offset. In general, the motor duty-cycle is calculated using:

error = (commandedValue - measuredValue)

dutyCycle = (kP * error) + (kI * integral(error)) + (kD * derrivative(error)) + (kF * commandedValue) + b

Parameters

kP	Proportional gain as a ratio between 0.0 and 4.0
kI	Integral gain as a ratio between 0.0 and 4.0
kD	Derivative gain as a ratio between 0.0 and 4.0
kF	Feed-forward gain as a ratio between -2.0 and 2.0
b	Feed-forward offset as duty-cycle between -2.0 and 2.0

◆ SetPosition()

void CANVenom::SetPosition ( double newPosition )

Reset the motor revolution counter (position) to the specified position.

Parameters

newPosition Value to assign motor position in revolutions

◆ StopMotor()

void CANVenom::StopMotor ( )

overridevirtual

Stop applying power to the motor immediately.

If Brake mode is active and the current control mode is Proportional or VoltageControl the motor will brake to a stop. Otherwise the motor will coast.

The enable() function must be called after a call to stopMotor() before motion may be commanded again.

The documentation for this class was generated from the following files:

src/main/native/include/CANVenom.h
src/main/native/cpp/CANVenom.cpp

Public Types

Public Member Functions

Detailed Description

Member Enumeration Documentation

◆ BrakeCoastMode

◆ ControlMode

◆ FaultFlag

◆ MotionProfileState

Constructor & Destructor Documentation

◆ CANVenom()

◆ ~CANVenom()

Member Function Documentation

◆ AddMotionProfilePoint()

◆ ClearLatchedFaults()

◆ ClearMotionProfilePoints()

◆ CompleteMotionProfilePath()

◆ Disable()

◆ Enable()

◆ EnableLimitSwitches()

◆ ExecutePath()

◆ Follow()

◆ Get()

◆ GetActiveControlMode()

◆ GetActiveFaults()

◆ GetAuxVoltage()

◆ GetB()

◆ GetBrakeCoastMode()

◆ GetBusVoltage()

◆ GetControlMode()

◆ GetCurrentMotionProfilePoint()

◆ GetDescription()

◆ GetDutyCycle()

◆ GetFirmwareVersion()

◆ GetFwdLimitSwitchActive()

◆ GetInverted()

◆ GetKD()

◆ GetKF()

◆ GetKI()

◆ GetKP()

◆ GetLatchedFaults()

◆ GetMaxAcceleration()

◆ GetMaxJerk()

◆ GetMaxPILimit()

◆ GetMaxSpeed()

◆ GetMinPILimit()

◆ GetMotionProfileIsValid()

◆ GetMotionProfilePositionTarget()

◆ GetMotionProfileSpeedTarget()

◆ GetMotionProfileState()

◆ GetNumAvaliableMotionProfilePoints()

◆ GetOutputCurrent()

◆ GetOutputVoltage()

◆ GetPIDTarget()

◆ GetPosition()

◆ GetRevLimitSwitchActive()

◆ GetSerialNumber()

◆ GetSpeed()

◆ GetTemperature()

◆ IdentifyMotor()

◆ InitSendable()

◆ PIDWrite()

◆ ResetPosition()

◆ Set()

◆ SetB()

◆ SetBrakeCoastMode()

◆ SetCommand() [1/2]

◆ SetCommand() [2/2]

◆ SetControlMode()

◆ SetInverted()

◆ SetKD()

◆ SetKF()

◆ SetKI()

◆ SetKP()

◆ SetMaxAcceleration()

◆ SetMaxJerk()

◆ SetMaxPILimit()

◆ SetMaxSpeed()

◆ SetMinPILimit()

◆ SetPID()

◆ SetPosition()