Top-Vu's approach is to integrate micro-inertial elements and electronics on a gallium arsenide (GaAs) substrate. Our strategy addresses the performance improvements by combining the material, device, circuit, and system technologies together. The objective of the Phase II project is to develop integrated GaAs based accelerometers with GaAs readout electronics for hypersonic vehicle guidance and navigation subsystems. The technical objectives are : a) Develop specification for the accelerometers, inertial measurement unit (IMU), and inertial navigation system (INS), b) Fabricate discrete accelerometers, c) Develop on-chip circuit and sensor integration (i.e., monolithic integration of micro-accelerometers with GaAs readout electronics), d) Develop GaAs readout electronics (i.e. analog integrated circuits: preamplifier, operational amplifier, analog switch, filter, sample/hold, analog to digital converter, and digital control circuits), and e) Develop a prototype system with sponsor specifications. Potential commercial applications abound in the medical, marine, transportation, military, and automotive industries. The applications for this sensor fall into four categories: control, instrumentation, stabilization, and navigation. Top-Vu will generate a GaAs cell library readily applicable to high performance sensors, micromachines, signal processors and data acquisition systems in the commercial industry. The GaAs cell library will be made available commercially through our services or agencies such as MOSIS/RMOSIS. Top-Vu's term interest is to merge these GaAs accelerometers with our other GaAs microchips to make powerful next generation microsystems.