rateDamp#

Executive Summary#

This module implements a feedback control law to damp the angular rates of the spacecraft until they are brought to zero.

Message Connection Descriptions#

The following table lists all the module input and output messages. 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
navAttInMsg	NavAttMsgPayload	Input navigation message
cmdTorqueOutMsg	CmdTorqueBodyMsgPayload	Output C++-wrapped message containing the rate-damping torque in Body-frame coordinates
cmdTorqueOutMsgC	CmdTorqueBodyMsgPayload	Output C-wrapped message containing the rate-damping torque in Body-frame coordinates

Detailed Module Description#

The control law implemented is the following:

\[\boldsymbol{u} = - P \boldsymbol{\omega}_\mathcal{B/N}\]

where \(P\) is a positive, user-defined scalar quantity. The control law is globally asymptotically stabilizing.

User Guide#

The required module configuration is:

attControl = rateDamp.RateDamp()
attControl.setRateGain(P)
attControl.modelTag = "rateDamp"

Class RateDamp#

class RateDamp : public SysModel#

Rate damp class.

Public Functions

RateDamp() = default#: Constructor.

~RateDamp() = default#: Destructor.

void reset(uint64_t currentSimNanos) override#

Reset method.

Reset method for the BSK module adapter interface.

Parameters:: currentSimNanos – [ns] Time the method is called
Returns:: void

void updateState(uint64_t currentSimNanos) override#

Update method.

Update method for the BSK module adapter interface. This method also calls the algorithm update method.

Parameters:: currentSimNanos – [ns] Time the method is called
Returns:: void

void setRateGain(double p)#

Setter method for rate feedback gain.

Set the module rate feedback gain

Parameters:: double – P
Returns:: void

double getRateGain() const#

Getter method for rate feedback gain.

Get the module rate feedback gain

Parameters:: double – measurementNoiseScale
Returns:: void

Public Members

ReadFunctor<NavAttMsgPayload> attNavInMsg#: Navigation input message.

Message<CmdTorqueBodyMsgPayload> cmdTorqueOutMsg#: Command torque output message.