I place back the battery holder and lay i-SOBOT on it to access the controller cover. It is fixed with 4 screws as shown below:
Nothing special to remove them and access to the controller. Here is a list of parts I have identified:
The tilt sensor is a simple switch made of a mercury drop that connects two electrodes (on the top side) when it is not vertical. It is a very simple sensor that can tell roughly the controller when i-sobot chest is horizontal or vertical.
Once the power, speaker (SPK1) and microphone connectors are unplugged, it is possible to remove the board that is just plugged in the various servo connectors. On this picture, you can see that it is easy to send your own signals to the servos. The shoulder servos are hidden by the head servo:
Others details in next message.