The present invention relates to a method and a device for determining the size and position of a parking space in relation to the position of a vehicle while the vehicle is driving past the parking space, the parking space extending longitudinally to the traffic lane and transversely to the traffic lane. An anchor insertion instrument is used to insert the anchor into the femur bore hole, the instrument having a pair of spaced apart pins to hold the bone anchor. Next, friction stir welding is performed to the protrusions 12, 22 and the filling material 30 using a rotary tool 80. First and second initiators are coupled to the switch.