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Learn about the system requirements for the LAMP instrument, including its components, development history, specifications, and constraints on the Lunar Reconnaissance Orbiter (LRO).
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System Requirements Review (SRR) August 16-17, 2005 LAMP Instrument Requirements Ron Black rkblack@swri.edu (210) 522-3562 Alan Stern astern@swri.edu (303) 546-0262
LAMP Instrument OverviewTheory of Operation LAMP is an integrated UV spectrograph composed of the following major elements: • A 42 x 65 mm off-axis paraboloidal primary telescope mirror. • A 51 x 51 mm toroidal holographic diffraction grating. • A 2-D imaging photon-counting microchannel plate (MCP) detector assembly with a once-openable vacuum cover/window assembly. • One entrance aperture • Lunar Terminator Sensor (LTS) to detect terminator crossings • Electronics that include: • Micro controller and C&DH electronics • Double Delay line detector electronics • Driver circuitry for actuators / heaters / switches, etc. • Redundant high voltage power supplies • Redundant low voltage power converters These elements are all packaged in a highly-baffled aluminum housing.
LAMP Instrument Overview LAMP (with LTS): 5.3 kg, 4.6 W 0.2º×6.0º slit 520-1800 Å passband 20 Åpoint source spectralresolution
LAMP Instrument Overview Development Epoch PFF UVSC Breadboard Built, vacuum tested 1993-1995 Rosetta Alice In flight for 14 months, operating nominally 1996-2001 New Horizons Alice Delivered 01 Sep 2004 Now in S/C test 2001-2004 LRO LAMP PDR: September 2005 2005-2008
LAMP Instrument Overview New Horizons Pluto-Alice UVS
LAMP Heritage • LAMP is a high heritage rebuild of the New Horizons Pluto Alice UV Spectrograph • Lunar Terminator Sensor is a new addition to LAMP unique to LRO • No changes to following subsystem hardware: • Mechanical structure • C&DH hardware • Optics • HVPS • Detector/Detector Electronics • Subsystem modifications: • Thermal isolation – added radiator • LVPS – to meet LRO power specifications • Harness – to accommodate LTS • Flight Software – minor changes to housekeeping packet, accommodate LTS signal to perform terminator crossing control
Selected Instrument Subsystem Level Requirements Level 3: Requirements 11239-OAP-01; 11239-GRAT-01
Instrument Constraints on LROMechanical/Thermal • LAMP shall be mounted on a stable instrument bench with its main aperture boresighted in the nadir direction (+z) and the spatial dimension of the LAMP slit normal to the direction of motion in flight along the lunar surface. • LAMP shall have a 40º full angle nadir centered clear (i.e. no obstacles) field of regard with the angle apex specified in the LAMP MICD. • Instrument boresight shall be aligned to S/C reference to within ±0.1º (3 sigma) in all three axes (TBD). • Instrument shall have alignment knowledge to S/C reference to within ±0.02º (3 sigma) in each of the three axes in flight. • LAMP shall be thermally isolated from the spacecraft. • LAMP and the LTS operating temperature: -10° to +40° C. Survival temperature range: -20° to +40° C. • The spacecraft shall provide operational and survival heater switch service.
Instrument Constraints on LROElectrical • The spacecraft shall provide two each switch services to LAMP – one for LAMP power A and one for LAMP power B. • LAMP shall transmit a block of science data at a physical clock rate of 1 MHz ± 1%. LAMP shall transmit science data using LVDS compliant driver chips. • LAMP shall transmit science data at an average rate of one block (64 kbytes) every 26 seconds. • LAMP shall transmit housekeeping data over an asynchronous 38.4 kbaud low speed RS-422 data bus. • LAMP shall support a parallel redundant housekeeping data interface. • LAMP shall receive a time code message from the spacecraft • One time message shall be transmitted per second. • LAMP shall receive the 1 PPS signal from the spacecraft via RS-422 compatible receivers.
Instrument Constraints on LROIntegration and Test • The spacecraft shall provide a harness from the LAMP safe/arm connector to a location that is easily accessible during I&T and launch campaign activities. • Alignment checks shall be performed at post-instrument alignment activity, post spacecraft vibration, post thermal vacuum test and post spacecraft delivery to KSC. • End-to-end UV throughput tests shall be performed at pre-instrument delivery, post-instrument delivery, post instrument integration, post-environmental tests, and post-delivery to KSC. • The spacecraft shall provide attachment points for the LAMP MGSE vacuum manifold assembly for LAMP end-to-end tests. • The spacecraft shall provide attachment points for LAMP MGSE UV lamp/collimator assembly for end-to-end tests. • LAMP contamination control shall be per document 11239-CCP-01.
Grating Grating Bracket Attach Htrs, TCs Attach Grating OAP Mirror OAP Mounting Bracket Attach Htrs, TCs Attach OAP Mirror Development FlowOptics Integration & Alignment Stage I Integration Activities performed during ROSETTA & NH ALICE fab/test To Stage II Integration Attach Grating Assy/ ZO Target Housing Structure Attach Slit Assy Attach OAP Assy Align Grating Attach Cube Align OAP Slit Assy Alignment Cube GSE Zero Order (ZO) Target
Detector POT Detector Electronics Release for Verification Testing Detector Assy Detector Bench & TVAC Test From Stage I Integration Detector Focus/Grating Alignment Tests* Integrate C&DH, LVPS, HVPSs, LTS Perform Baseline Functional Test Housing Structure Mount Detector Attach POT Integrate Base Level S/W Build Functional Test/HVPS Calibration C&DH and LVPS Electronics HVPSs (2) * Tests performed in vacuum radiometric chamber with EGSE HVPS. Development FlowDetector/Electronics Integration Stage II Integration Activities performed during ROSETTA & NH ALICE fab/test LTS Assy
Instrument Current Status • Trades • Spacewire interface: closed - project decides to keep heritage interface • Lunar Terminator Sensor: closed - project directs LAMP to implement • On-going Trades • Thermal Isolation – radiator size? • Mounting location • Current Analyses • Thermal • Current Hardware Prototype Development • LTS Electronics
Summary • LAMP requirements are well defined and firm. Instrument constraints have been conveyed to spacecraft and are documented in the LRO MRD. • Instrument design is also well defined and mature. • Current Status • Procurement of engineering and flight parts underway • Fabrication/assembly of engineering C&DH and LVPS modules underway for GSFC to perform I/O testing in late fall. • LTS electronics prototype testing underway • Procurement of optics initiated • Procurement of detector electronics in progress.
