Robot arms can be used to pick things up and move them around. With different degrees of freedom the arms can grip, rotate and swivel to move similar to a hand, wrist, elbow and shoulder.
Pan & Tilt modules provide two degrees of freedom rotating about the horizontal and vertical axis. Sensors can be mounted on a pan & tilt bracket to allow a survey of the environment to be done. Bubble guns can be used to go on the offence.
The arms, grippers and pan & tilt modules can be easily controlled from a microcontroller using a servo library or from a computer using a servo controller over USB.