Servo Gripper - HELP :)

Mariana_Sousa · September 23, 2019, 8:22pm

Hi, good afternoon.

I own a pixhawk 2.4.8, tried several firmwares (1.9, 3.6.10, 3.5.3) and could not find the servo gripper function.
I’m trying to do a mission where the drone take off, go to the destination, land, open the servo system and take off plus RTH, but I can not make this happen. The closest we got was the drone taking off doing the mission, land, but couldn’t release the package.

The servo work with manual control on the radio, works on the MP as a camera trigger or as normal servo.

Can anyone help me or give me a light please.

Tks.

peterbarker · September 24, 2019, 3:32am

This autotest is doing what you’re trying to do:

github.com

ardupilot/ardupilot/blob/master/Tools/autotest/arducopter.py#L2510




    tstart = self.get_sim_time()
    while self.get_sim_time_cached() - tstart < 10:
        m_pos = self.mav.recv_match(type='LOCAL_POSITION_NED',
                                    blocking=True)
        pos = rotmat.Vector3(m_pos.x, m_pos.y, m_pos.z)
        delta_ef = pos - dest
        dist = math.sqrt(delta_ef.x * delta_ef.x + delta_ef.y * delta_ef.y)
        self.progress("dist=%f" % (dist,))


def fly_payload_place_mission(self):
    """Test payload placing in auto."""
    self.context_push()


    ex = None
    try:
        self.set_analog_rangefinder_parameters()
        self.set_parameter("GRIP_ENABLE", 1)
        self.set_parameter("GRIP_TYPE", 1)
        self.set_parameter("SIM_GRPS_ENABLE", 1)
        self.set_parameter("SIM_GRPS_PIN", 8)

The critical bit you’re missing is

self.set_parameter(“SERVO8_FUNCTION”, 28)

The text for that is “EPM” - which could be rather clearer (or, you know,
actually correct).

Peter