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CINEMA Mechanical Subsystem PDR August 22, 2008 David Glaser/Paul Turin. MECHANICAL -- Overview. Mechanical Requirements Mechanical Subsystems Chassis Solar Array Communication Hardware Torque Coils Sun Sensor Magnetometer Boom STEIN Mass Budget. MECHANICAL – Requirements.
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CINEMA Mechanical Subsystem PDR August 22, 2008 David Glaser/Paul Turin CINEMA PDR- MEC
MECHANICAL -- Overview • Mechanical Requirements • Mechanical Subsystems • Chassis • Solar Array • Communication Hardware • Torque Coils • Sun Sensor • Magnetometer Boom • STEIN • Mass Budget CINEMA PDR- MEC
MECHANICAL – Requirements • Meet Cubesat Interface and Mass Specifications • Withstand Launch Environmental Loads • Keep Internal Magnetic Field to a Minimum • Design • Bus Chassis • House All Components in Bus • STEIN Instrument Attenuating Shutter • Magnetometer Boom Deployment Mechanism • Magnetometer Harness • Harnessing (TBD) CINEMA PDR- MEC
MECHANICAL – CubeSat Req. • CINEMA must fit inside a P-Pod (Poly-Picosatellite Orbit Deployer) and be deployed without jamming • No parts may separate from the satellite (no space debris created) • No pyrotechnics allowed • Maximum Mass: 3 kg (negotiable?) • Kill Switch, Deployment Switch, and Spring Plungers P-POD CAD Image http://cubesat.atl.calpoly.edu/pages/reference/pictures.php KC-135 P-POD Test Video http://cubesat.atl.calpoly.edu/pages/reference/videos.php CINEMA PDR- MEC
MECHANICAL -- Chassis Rails Hard Anodized 100 mm 340.5 mm 100 mm • 0.050 inch thick Aluminum Sheet Metal • Ends – ¼ inch Aluminum • Rail Dimensions to Cubesat Specifications CINEMA PDR- MEC
MECHANICAL -- Chassis Spring Plunger Deployment Switch Spring Plunger CINEMA PDR- MEC
MECHANICAL -- Overview Genesat Avionics Box Mag Boom Deployer STEIN Science Radio Transmitter Outboard Magnetometer Components will generally be fastened with a #4-40 flathead screw, countersunk into chassis. Inboard Magnetometer Sun Sensors CINEMA PDR- MEC
MECHANICAL – Solar Array • 10 Panels (3 on each long side 1 Panel on top, bottom, and short sides) • Each Panel 3 x 3.2 inches (7.6 x 8.1 cm) • Nominal Bus Voltage is 9.2 V • Therefore need 4x PV cells on each panel • Typical cells too large • TASC cells are small enough, but require assembly, and have no coverglass CINEMA PDR- MEC
MECHANICAL – Solar Array TASC PV Cells (Spectrolab) 1.55 cm (.61 inches) 3.18 cm (1.25 inches) • 20 Cells/Panel • 8 Panels • Cost of Cells: $500 • No Coverglass Included • Cost of Assembly ? CINEMA PDR- MEC
MECHANICAL - Communication • Science Data Transmitter • Telemetry Transceiver • 2 Science Data Patch Antennas • 2 Telemetry Patch Antennas Patch Antennas CINEMA PDR- MEC
MECHANICAL – Torque Coils Coils located on STEIN Side and Bottom Torque Coil Rail CINEMA PDR- MEC
MECHANICAL – Torque Coils • 28 AWG Magnet Wire (0.32 mm diam./ max current 1.4 A) • 62 Turns (50 m of wire) • Coil Length: 0.317 m Width: 0.086 m • Effective Coil Area: 0.0256 m2 • Electrical Resistance: 10.65Ω CINEMA PDR- MEC
MECHANICAL – Sun Sensors • Field of View Per Sensor: 5° Azimuth x 41° Elevation • 2 Sensors @ 45° to Vertical, 90° to Each Other • Sensor: Phototransistor (Motorola MRD300) • Prototype Tested • Load Resistor: 1 kΩ • Vcc = 5 V • Power: ~25 mW (Light); ~10µW (Dark) 2.3 cm 1.6 cm CINEMA PDR- MEC
MECHANICAL – Sun Sensors Prototype Scanned Across Sun @ 1 RPM Averaged Data Nominal 1.4° Width of Opening 4.6° > 1 Volt Simulation of Earthshine Rise Time ~120 ms CINEMA PDR- MEC
MECHANICAL – Sun Sensors Raw Data Large Noise Peaks Probably Due to DC Motor Noise ~ -0.3 V Slope of Rise: ~ 35 V/sec Timing Error = 9 ms < 0.1° CINEMA PDR- MEC
MECHANICAL – Mag & Boom CINEMA PDR- MEC
MECHANICAL – Mag & Boom • 1 meter stacer boom • Held by TiNi P5 Pin Puller • Magnetometer in 2 x 2 x 2 cm compartment • Magnetometer Harness • 18 strands of 36 AWG magnet wire • Aracon braid for Harness Jacket • Non-Magnetic Braid on 6 cm closest to sensor • Fixed to Mag Mount and Base of Boom via Screw-Down Fixtures • 18-pin Connector at End CINEMA PDR- MEC
MECHANICAL – Mag & Boom Magnetometer Mount Magnetometer Chassis Mounts CINEMA PDR- MEC
MECHANICAL – Mag & Boom TiNi Pin Puller Stowed Stacer Boom Release Pin CINEMA PDR- MEC
MECHANICAL – Mag & Boom Harness Details Harness Constraining Fixtures String Cannister CINEMA PDR- MEC
MECHANICAL – Mag & Boom CINEMA PDR- MEC
MECHANICAL – Mag & Boom Harness Assembly CINEMA PDR- MEC
MECHANICAL – Mag & Boom Anti-vibration Clearance 0.02 inches (0.5 mm) CINEMA PDR- MEC
MECHANICAL – Mag & Boom Prototype Harness • 36 AWG Magnet Wire with Polythermalize Insulation • Examined for Wear Under Microscope • 18 Strands Wound with a winding machine, 1 turn/cm • Tension on cable not controlled • Inserted into Aracon Braid • Harness Deploy Tested on Mockup Boom CINEMA PDR- MEC
MECHANICAL – Mag & Boom Boom & Harness Mock Up – Stowed Configuration ID 2.54 cm Annulus 3.8 mm CINEMA PDR- MEC
MECHANICAL – Mag & Boom Boom & Harness Mock Up – Deployment Test Video (half speed) CINEMA PDR- MEC
MECHANICAL -- STEIN • Collimator: 40° x 60° FOV • High Voltage Plates: 4 mm separation, ~1 cm from detector • Attenuator: Swinging Shutter with BeCu Foil • Actuated by Two SMA “Nanomuscles” • Flight Heritage from THEMIS and other Missions • Low Electrical and Magnetic Noise • Microswitch Overcenter Mechanism CINEMA PDR- MEC
MECHANICAL -- STEIN Collimator Attenuator Detector and Electronics CINEMA PDR- MEC
MECHANICAL -- STEIN Collimator Electric Field Plates 60° CINEMA PDR- MEC
MECHANICAL -- STEIN Attenuator Shutter Shutter with BeCu Foil 4 Pixel Detector CINEMA PDR- MEC
MECHANICAL -- STEIN Actuators – Shutter Closed Nanomuscle Actuator Pivot Lever Countermass Capton Yoke Cam/Lever CINEMA PDR- MEC
MECHANICAL -- STEIN Actuators – Shutter Open CINEMA PDR- MEC
MECHANICAL -- STEIN Attenuator Overcenter Mechanism HM Microswitch Spring Plunger Cam Bearing CINEMA PDR- MEC
MECHANICAL -- STEIN Attenuator Mechanism Specifications CINEMA PDR- MEC
MECHANICAL -- STEIN Attenuator Mechanism Analysis Maximum Torque from Nanomuscle and Lever CINEMA PDR- MEC
MECHANICAL -- STEIN Attenuator Overcenter Mechanism – Cam Analysis CINEMA PDR- MEC
MECHANICAL -- STEIN Attenuator Overcenter Mechanism – Cam Analysis CINEMA PDR- MEC
MECHANICAL -- STEIN Attenuator Mounting – How to Locate These Components CINEMA PDR- MEC
MECHANICAL -- STEIN 1. Attenuator Mounting – Collimator Shell CINEMA PDR- MEC
MECHANICAL -- STEIN 2. Attenuator Mounting – Add Mount Plate CINEMA PDR- MEC
MECHANICAL -- STEIN 3. Attenuator Mounting – Add Shutter and Actuators CINEMA PDR- MEC
MECHANICAL -- STEIN 4. Attenuator Mounting – Add Switch Mounts CINEMA PDR- MEC
MECHANICAL -- STEIN 5. Attenuator Mounting – Add Switches #0-80 Set Screw for Switch Location Adjustment CINEMA PDR- MEC
MECHANICAL – Mass Budget Highlighted figures Have changed since the proposal. Most other figures are rough estimates. CINEMA PDR- MEC