Module: rwMotorVoltage

Executive Summary

This module computes the RW motor voltage from the command torque.

The module PDF Description. contains further information on this module’s function, how to run it, as well as testing.

Message Connection Descriptions

The following table lists all the module input and output messages. The module msg connection is set by the user from python. The msg type contains a link to the message structure definition, while the description provides information on what this message is used for.

Module I/O Messages
Msg Variable Name	Msg Type	Description
voltageOutMsg	ArrayMotorVoltageMsgPayload	RW motor voltage output message
torqueInMsg	ArrayMotorTorqueMsgPayload	commanded RW motor torque input message
rwParamsInMsg	RWArrayConfigMsgPayload	RW array configuration input message
rwAvailInMsg	RWAvailabilityMsgPayload	(optional) RW device availability message
rwSpeedInMsg	RWSpeedMsgPayload	(optional) RW device speed message

Functions

void SelfInit_rwMotorVoltage(rwMotorVoltageConfig *configData, int64_t moduleID)

This method initializes the configData for this module. It creates the output message.

Parameters:

configData – The configuration data associated with this module
moduleID – The ID associated with the configData

Returns:

void

void Update_rwMotorVoltage(rwMotorVoltageConfig *configData, uint64_t callTime, int64_t moduleID)

Update performs the torque to voltage conversion. If a wheel speed message was provided, it also does closed loop control of the voltage sent. It then writes the voltage message.

Parameters:

configData – The configuration data associated with the module
callTime – The clock time at which the function was called (nanoseconds)
moduleID – The ID associated with the configData

Returns:

void

void Reset_rwMotorVoltage(rwMotorVoltageConfig *configData, uint64_t callTime, int64_t moduleID)

This method performs a reset of the module as far as closed loop control is concerned. Local module variables that retain time varying states between function calls are reset to their default values.

Parameters:

configData – The configuration data associated with the module
callTime – Sim time in nanos
moduleID – The ID associated with the configData

Returns:

void

struct rwMotorVoltageConfig

#include <rwMotorVoltage.h>

module configuration message

Public Members

double VMin: [V] minimum voltage below which the torque is zero

double VMax: [V] maximum output voltage

double K: [V/Nm] torque tracking gain for closed loop control.

double rwSpeedOld[MAX_EFF_CNT]: [r/s] the RW spin rates from the prior control step

uint64_t priorTime: [ns] Last time the module control was called

int resetFlag: [] Flag indicating that a module reset occured

ArrayMotorVoltageMsg_C voltageOutMsg: voltage output message

ArrayMotorTorqueMsg_C torqueInMsg: Input torque message

RWArrayConfigMsg_C rwParamsInMsg: RW array input message

RWSpeedMsg_C rwSpeedInMsg: [] The name for the reaction wheel speeds message. Must be provided to enable speed tracking loop

RWAvailabilityMsg_C rwAvailInMsg: [-] The name of the RWs availability message

RWArrayConfigMsgPayload rwConfigParams: [-] struct to store message containing RW config parameters in body B frame

BSKLogger *bskLogger: BSK Logging.