Module: arrayMotorTorqueToSingleActuators

Executive Summary

The arrayMotorTorqueToSingleActuators module is an adapter that converts an array motor torque command message into a set of scalar actuator command messages. The module reads a single input message of type ArrayMotorTorqueMsgPayload, which contains a motor torque vector \(\boldsymbol{u}\). At each update, the module writes \(N\) output messages of type SingleActuatorMsgPayload such that

\[u_i^{(\text{out})} = u_i, \quad i = 0, 1, \ldots, N-1\]

where \(u_i^{(\text{out})}\) is the scalar command written to the \(i\)-th actuator output message. This supports connecting flight software modules that publish array-valued motor commands to simulation actuators that expect individual scalar actuator command messages.

Message Connection Description

The following table lists the module input and output messages.

Module I/O Messages

Msg Variable Name	Msg Type	Description
torqueInMsg	ArrayMotorTorqueMsgPayload	Input message containing the motor torque array
actuatorOutMsgs	SingleActuatorMsgPayload	Vector of output messages containing one scalar actuator command per actuator

Module Functions

Below is a list of functions that this simulation module performs

• Reads the incoming ArrayMotorTorqueMsg input

• Copies each array entry into the corresponding scalar SingleActuatorMsg output

• Writes all scalar actuator output messages each update cycle

Module Assumptions and Limitations

• The mapping is order-preserving: array index \(i\) maps to output actuator index \(i\)

• The module assumes \(N\) does not exceed the size of the input motor torque array provided by ArrayMotorTorqueMsgPayload

Test Description and Success Criteria

The unit test for this module is defined in test_arrayMotorTorqueToSingleActuators. The test initializes the module with a configurable number of actuators \(N\), publishes a known torque vector to the input message, and runs one simulation step. The test passes if each scalar output message matches the corresponding input array element to within numerical tolerance.

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class ArrayMotorTorqueToSingleActuators : public SysModel

#include <arrayMotorTorqueToSingleActuators.h>

Adapter module that converts an ArrayMotorTorqueMsg into one SingleActuatorMsg per actuator using direct index mapping.

Public Functions

ArrayMotorTorqueToSingleActuators()

Default constructor.

explicit ArrayMotorTorqueToSingleActuators(uint32_t numActuators)

Constructor specifying number of actuators.

Parameters:

numActuators – Number of output actuators.

~ArrayMotorTorqueToSingleActuators() override = default

Destructor.

void Reset(uint64_t CurrentSimNanos) override

Reset the module.

Parameters:

CurrentSimNanos – Current simulation time [ns].

void UpdateState(uint64_t CurrentSimNanos) override

Read array torque message and publish scalar actuator commands.

Parameters:

CurrentSimNanos – Current simulation time [ns].

void setNumActuators(uint32_t numActuators)

Set the number of actuators.

Parameters:

numActuators – Number of actuators.

Public Members

ReadFunctor<ArrayMotorTorqueMsgPayload> torqueInMsg

Input motor torque array.

std::vector<Message<SingleActuatorMsgPayload>> actuatorOutMsgs

Scalar actuator outputs.

BSKLogger bskLogger

BSK Logging.

Private Functions

void ensureSizes()

Ensure internal buffers are correctly sized.

Private Members

uint32_t numActuators

Number of actuators.