How to remove the forearm and put it back

This document lists the different steps to disassemble the iCub forearm V1, and how to remove it entirely and safely.

Tools required

1. Allen key ???mm.

2. Small/Medium Phillips screwdriver

3. Tweezers : This one is not mandatory but helps a lot to disconnect safely card plugs.

First step : remove the arm rigid cover

• Remove the skin screws from inside the biceps to the bottom screw through the top. It is convenient to leave the last screws, keeping the skin on the cover.

• Once the skin is removed, 3 screws come out under the arm. They maintain electronic cards inside the arm and have to be be removed.

• Remove the 4 screws that maintain the rigid cover. There are 2 small near the elbow (memento : the shortest one is from the inside of the arm). 2 others are bigger and located on the shoulder side.

  Now, the rigid cover can be carefully removed. To remove it totally, disconnect the N7 wire (skin sensors power supply), and the black wire connected to the filter (skin sensors data).

Second step : disconnect forearm wires

• Remove the white connector. It is the emergency stop circuit.

• Remove the N7 and 2N1 connectors.

• Disconnect the cards. There are 3 (1B2, 1B3 and 1B4), each one is connected with one 8-pins connectors, which carries power supply (in theory also interchangeables), the original links are

cable	board
L3	1B4
L4	1B2
L5	1B3

All forearm wires should now be totally free.

Third step : disassembling the forearm

Mechanically speaking, the forearm is only linked by 3 screws. They are located on the elbow, and you can remove them easily if you bend the arm.

Optional : How to remove the forearm rigid cover

• Remove the skin, leaving the last screws may be useful to hold the skin.

• Remove the 8 screws that maintain the rigid over. Some screws are tricky because they are a bit screwed in the plastic.

• Disconnect the N7 wire to remove totally the cover.