1. Lunar Penetrator 1 WIRING ARCHITECTURE Overview Presentation 2009-01-23Karim A. Barakat 1

2. Presentation Outline Derived Requirements Subsystem Components Power Telemetry collection & Command distribution Design Constraints & Solutions Future Work 2009-01-23 2 Karim A. Barakat

3. Derived Requirements Shall have low outgassing levels Shall operate and survive 15,000 g Shall operate and survive thermal shock Shall consume no more than 5% - 10% of dry mass 2009-01-23 3 Karim A. Barakat

4. Options Digital Data – Bus architecture (e.g. CAN bus, I²C bus) – Simple set of wires (e.g. RS 422) Analog Data – Dedicated wires Power – Power bus – Point to point 2009-01-23 4 Karim A. Barakat

5. Subsystem Components 2009-01-23 5 Karim A. Barakat Wiring HarnessConnectors Dielectric Insulating Material Tetrafluoroethylene or crossed-linked polyolefin Conductor Space grade options: Silver plated copper Power: e.g. AWG 22 or AWG 30 D connector Electrical: e.g. 9-pin electrical D-type

6. Power 2009-01-23 6 Karim A. Barakat Power Control Unit (Distribution & Control) +3.3 V+5 V-5 V+28 V Batteries CDH Payload’s Instruments Communications Propulsions Voltage Regulator

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9. Design constraints & Solutions Electromagnetic InterferenceSeparate Comms wires from rest Radiation exposureImplementation of rad resistant insulation Undesirable current fluctuation can occur Implement current limiters through input protection diodes Excess power can sometime dissipate back into the integrated circuit Use resistors to dissipate power Can’t use wet electrolytic capacitorsUse tantalum, glass or ceramic capacitors Can’t use variable resistanceDiodes act as voltage limiters 2009-01-23 9 Karim A. Barakat

10. Future Work 2009-01-23 10 Karim A. Barakat Gather necessary information from subsystems Work more on the power distribution layout Perform trade off studies on material selection Develop 2 or more different solutions Perform trade off study between proposed solutions Finalize and model wiring architecture

11. Lunar Penetrator 1 QUESTIONS? 2009-01-23Karim A. Barakat 11