PSAS Autonomous Recovery System project The PSAS Autonomous Recovery System project borrows heavily from knowledge gleaned from the development of the Spacewedge autonomous vehicle, which was developed as part of the NASA Spacecraft Autoland Project (1991-1996). Engineering Task List for ARS1 Development System : ARS1 will consist of a working device which prototypes the electronic and controller functions, but is not optimized for size, weight, shape, load, etc. It will serve as a fully flyable system (which can be dropped from an airplane, but not deployed from a rocket) which will be used to develop the electronic and mechanical systems, as well as algorithms for control and filtering of sensor data. Phase 1 - Deliver a flyable system that can be controlled in open loop mode, and visually steered via the GCC remote controller. Design, build, test: CANbus implementation with three PIC16F84 modules (PSU Capstone project) CANbus CC modules (PIC17C756 dev boards, LINX modems) (PSU Capstone project) CANbus MC module w/mechanical crawler Redesign motor controller if necessary. Determine the steady state relationship between crawler position and spin rate. Do this by dropping the ARS from a suitable height and making visual observations. Repeat after adjusting crawler position. Determine if controller has adequate gain to implement a step function input whose response contains enough information to determine a transfer function for yaw position vs. crawler position. If answer to above is no, then redesign MC to increase gain, while still maintaining open loop stability. Phase 2 - Design and build the heading tracker Build a suitable steady state compass: Design and build the CANbus MGN module, utilizing a Honeywell HMC2003 3-axis magnetometer. If required for adequate steady state response. Design and build the CANbus INC module, utilizing an Advanced Orientation systems DX-045D-045 dual axis inclination sensor. Design and build the CANbus FC module, which will implement a compass algorithm which provides adequate steady state response. Characterize the steady state response of the compass. Do this by strapping a standard hiker's compass to the ARS support tube and comparing outputs for a full 360 deg. If necessary, improve dynamic response capability of electronic compass. Characterize the dynamic response. Add a temporary yaw position indicator (laser pen light) and suspend the ARS in a room with a grid on the wall. As the ARS is rotated, use a video camera to simultaneously film the laser spot on the grid, and a laptop display of the compass reading from the FC module. If dynamic response is inadequate, design and build the CANbus GYR module with at least a yaw rate sensor. Update CANbus FC module to improve dynamic response by implementing a complementary filter to blend the outputs from the steady state compass and the yaw rate sensor. Characterize steady state and dynamic response as was done for the steady state compass. Derive a transfer function for the electronic compass. Design and implement the heading tracker algorithm in CANbus FC module. Phase 3 - Implement Autonomous Flight Control Design and build the CANbus GPS module. Test for ability to acquire and maintain satellite fixes in the presence of high power transmission from the Remote CC module. Develop autonomous control algorithms in the CANbus FC module. Design and build CANbus PYR module and mechanical flare device. Test and rework. Design and build CANbus SNR module and add flare control to autonomous algorithms in CANbus FC module.