CAV-ARC V1.1 AIWs Motion Actuation Subsystem

1       Functions	2       Reference Model	3       I/O Data
4       Functions of AI Modules	5       I/O Data of AI Modules	6      AIW, AIMs, and JSON
7       Reference Software	8       Conformance Testing	9     Performance Assessment

1        Functions of Motion Actuation Subsystem

The Motion Actuation Subsystem (MAS):

1. Transmits spatial and weather information gathered from its sensors and mechanical subsystems to the Environment Sensing Subsystem (ESS).
2. Receives AMS-MAS Messages from the Autonomous Motion Subsystem (AMS).
3. Translates AMS-MAS Message into specific Commands to its own Brake, Motor, and  Wheel mechanical subsystems.
4. Receives Responses from its Brake, Motor, and  Wheel mechanical subsystems.
5. Packages Responses into and sends AMS-MAS Messages to Autonomous Motion Subsystem.

2        Reference Architecture of Motion Actuation Subsystem

Figure 1 represents the Reference Model of the Motion Actuation Subsystem (CAV-MAS) V1.1.Figure 1 – Motion Actuation Subsystem Reference Model

The operation of the Motion Actuation Subsystem unfolds as follows:

1. AMS Command Interpretation
   1. Interprets the AMS-MAS Messages received from AMS and issues commands to the Brake, Motor, and  Wheel mechanical subsystems.
2. MAS Response Analysis
   1. Interprets the responses received from the Brake, Motor, and  Wheel mechanical subsystems and sends AMS-MAS Messages to to AMS.
3. MAS Spatial Attitude Generation
   1. Computes the initial Ego CAV’s Spatial Attitude Attitude using Spatial Data (Odometer, Speedometer, Accelerometer, and Inclinometer) Data
   2. Sends the initial  Spatial Attitude Attitude to the ESS.
4. Ice Condition Analysis
   1. Augments Weather Data analysing the responses of the Brake, Motor, and  Wheel mechanical subsystems.
   2. Sends augmented Weather Data to ESS.

3        I/O Data of Motion Actuation Subsystem

Table 1 gives the input/output data of Motion Actuation Subsystem.

Table 1 – I/O data of Motion Actuation Subsystem

Input	Comments
Spatial Data	Collection of distance, velocity,  acceleration, and inclination data.
Weather Data	Data such as humidity, pressure, temperat­ure.
AMS-MAS Message	Message including motion information.
Motor Response	Information on effects of applied motor force.
Wheel Response	Information on effects of applied Wheel rotation force.
Brake Response	Information on effects of applied brake force.
Output	Comments
Spatial Attitude	Position, Orientation and their velocity and acceleration vectors.
Weather Data	Data such as humidity, pressure, temperat­ure, ice condition.
Motor Command	Applied motor torque.
Wheel Command	Applied wheel torque.
Brake Command	Applied brake deceleration.
AMS-MAS Message	Message including results of MAS Response analysis.

4        Functions of Motion Actuation Subsystem’s AI Modules

Table 2 gives the AI Modules of Autonomous Motion Subsystem.

Table 2 – Functions of Motion Actuation Subsystem’s AI Modules

AIM	Function
MAS Spatial Attitude Generation	Computes Ego CAV’s Spatial Attitude using Spatial Data.
AMS Command Interpretation	Receives, analyses, and actuates AMS-MAS Message into specific commands to Brakes, Wheels, and Motors.
MAS Response Analysis	Receives and analyses responses from Brakes, Wheel, and Motors and sends the MAS-AMS Response to AMS.
Ice Condition Analysis	Adds ice condition information to input Weather Data.

5        I/O Data of Motion Actuation Subsystem’s AI Modules

Table 3 gives, for each AIM (1^st column), the input data (2^nd column) from which AIM (column) and the output data (3^rd column).

Table 3 – I/O Data of Motion Actuation Subsystem’s AI Modules

AIM	Input	Output
MAS Spatial Attitude Generation	– Spatial Data	– Spatial Attitude
AMS Command Interpretation	– AMS-MAS Message	– Brake Command – Motor Command – Wheel Command
MAS Response Analysis	– Brake Response – Motor Response – Wheel Response	– AMS-MAS Message
Ice Condition Analysis	– Brake Response – Motor Response – Wheel Response – Weather Data	– Weather Data

6     AIW, AIMs, and JSON

AIW	AIMs	AIM Names	JSON
CAV-MAS		Motion Actuation Subsystem	X
	CAV-MSG	MAS Spatial Attitude Generation	X
	CAV-AMI	AMS-MAS Message Interpretation	X
	CAV-MRA	MAS Response Analysis	X
	CAV-ICA	Ice Condition Analysis	X

7     Reference Software

 

8      Conformance Testing

 

9     Performance Assessment