check_motion (Manual Mode)

This section explains how to use check_motion during Manual (Teach) operations. Although defined in 3.1 Common, it is especially useful when monitoring whether a robot motion command is currently active, being planned, or completed during manual or step-based movement.

Typical usage

• Confirm that the robot has completed a move command before issuing the next.

• Use in polling loops or step-wise teaching sequences to synchronize motions.

• Verify the robot is idle before applying safety actions (e.g., servo_off).

Note

• The function is non-blocking and can be safely used in tight polling loops.

• Recommended to combine with mwait() or get_robot_state() for robust synchronization.

Example: Wait until motion is complete before next move

// Preconditions:
// - Connection established (open_connection)
// - Manual (Teach) mode active
// - Servo power ON

// 1) Execute first joint motion
float q0[6]  = {0, 0, 90, 0, 90, 0};
float q99[6] = {0, 0, 0, 0, 0, 0};
drfl.movej(q0, 60, 30);

// 2) Wait until the previous motion completes
while (true) {
    int state = drfl.check_motion();
    if (state == 0) { // motion completed
        printf("[check_motion] Motion finished. Proceeding...\n");
        break;
    } else if (state == 1) {
        printf("[check_motion] Motion being calculated...\n");
    } else if (state == 2) {
        printf("[check_motion] Motion in progress...\n");
    }
    std::this_thread::sleep_for(std::chrono::milliseconds(200));
}

// 3) Start next motion after confirming completion
drfl.movej(q99, 60, 30);

Tips

• check_motion() is ideal for synchronization in step-by-step motion tests.

• Always ensure the function returns 0 (idle) before sending new move commands.

• Useful before safety procedures like servo_off or release_protective_stop.

• When building teaching GUIs, use it to display motion state indicators (Idle / Calculating / Moving) in real time.