The JAUS Management service is a state-machine for managing component life-cycle to help individuals understand how a component will react to incoming commands and quires.
How Do you use it?
The first step in understanding the management service requires a knowledge of some vocabulary that may be mistaken or confused easily. Each of the following items represent different commands and the states that the service will enter following their execution.
This command instructs the component to release all resources and then begin to shut down properly.
This message is used to transition the service to a waiting state. This is not a ready state and the component may seem unresponsive if in the standby state.
This message is used to transition the component to the ready state. This command should be used before sending commands to the services derived from the management service.
*If the component is not in the ready state commands meant to set properties in services derived from the management service will not work. For-example : If you were to build the openjaus sdk and run the PdDemo and PdClient applications, after taking control of the server the client can not send the set wrench command. First the User must send a resume command to the PdDemo in order to move it to the ready state. When first booting a module and taking control the Resume control should be viewed as a Start command. Though you can still query the service when in standby you can never alter information until the service has entered the ready state.
This message triggers the component to reinitialize. This means returning the INIT State.
This message is used to alert the component to a safety critical situation. The component that sends the emergency command should also set the message priority to the safety critical priority range. This will move the component into the Emergency state.
This message notifies the receiving component that the current emergency condition is to be reset. This also indicates that the component that component is ready to transition back to the Ready or Standby states, provided all emergency conditions have been cleared.
This message is used by clients of this service to query the state of the service. (Init, Ready, Standby, Shutdown, Failure, Emergency)
This message is used to report the current status of the sender of the message. (Init, Ready, Standby, Shutdown, Failure, Emergency)