7.2 Access Control Loss

A. Error Case

Commands sent without control authority are not executed. The controller reports a warning alarm through TOnLogAlarmCB for every fourth such command.

This indicates that your client program cannot obtain robot control authority from the controller.

B. Root Cause Analysis

The Doosan Robot system allows only one active client to have control authority at a time. If another process — such as DART Studio, another API client, or an RT monitoring tool — is currently connected, additional clients will be denied access until the holder answers a request with MANAGE_ACCESS_CONTROL_RESPONSE_YES. A client that sends MANAGE_ACCESS_CONTROL_FORCE_REQUEST takes control without an answer.

This issue often occurs when:

  • DART Studio is left connected in Monitor or Control Mode.

  • A previous API session did not close properly (e.g., abnormal termination).

  • Multiple applications are trying to control the same robot simultaneously.

C. Solution

  1. Open DART Studio and check whether another connection is active.

    • Navigate to Settings → API Control Authority.

    • Click Release Control if another client holds it.

  2. If using multiple devices, ensure only one program connects to the same robot IP.

  3. Restart the controller service to clear stale sessions (if necessary):

    sudo systemctl restart dsr-control

  4. In your client code, always close the connection after use:

    Drfl.close_connection();

Note

The controller ignores every request from a client without control authority, except get_system_version, get_safety_configuration and setup_monitoring_version. A client without control authority still receives monitoring data, state and alarm callbacks; use the monitoring getters (get_current_posj, get_robot_state, …) for position and state information.