 Draper combined ideas from his integrating gyroscopes, which were mounted in cans that floated in fluids that were held in place by jeweled bearings, with the recovered V2 accelerometer by floating the pendulum-gyroscope portion.The more generic name of PIGA was suggested by Dr Draper due to the addition of various refinements such as electromagnetic or optical sensing of pendulum position.Such accelerometers were used in the Titan II and Polaris Systems and Minuteman systems.