Galileo Systems Interim Report Low Cost High Altitude Sensor Platform January 12, 2004 K. Mark Caviezel, Engineer, PI Dr. Gary E. Snyder, President (720)333-2248 Richard Powers, Engineer Wil McCarthy, Engineer 1
Progress Conceptual study of station keeping HAA platform conducted, near term feasibility appears good evolved finless airship chosen as lowest risk option low drag low cost solar power COTS power storage technology 2
Proposed Family of Vehicles Graf Galileo Day Flier 90 feet long 22.5k cubic feet Graf Galileo Day/Night Station Keeper (DNSK) 320 feet long 1.0 million cubic feet Graf Galileo One 640 feet long 8 million cubic feet, small radar Graf Galileo Two 830 feet long 17.6 million cubic feet large radar 3
Graf Galileo Vehicle Family Day Flier DayNight Stationkeeper Graf Galileo One Graf Galileo Two Payload 0 lb 0 lb 4000 lb 12000 lb Mass 109 lb 5400 lb 40000 lb 91000 lb Displacement 22 K cuft 1 M cuft 8 M cuft 17 M cuft Length 90 ft 320 ft 640 ft 820 ft Motor Power 660 W 8500 W 34000 W 55000 W Propeller Diameter 14 ft 48 ft 96 ft 120 ft Solar Power 680 W 25000 W 160000 W 390000 W Solar Area 190 sqft 7100 sqft 44000 sqft 110000 sqft Payload Power 0 W 0 W 12000 W 75000 W Storage Energy 300 Whr 15 kwhr 970 kwhr 2400 k Whr Storage Weight 7 lb 2900 lb 18000 lb 44000 lb 4
Graf Galileo Day Flier 90 feet long 22.5 thousand cubic feet displacement GVW 110 lbs. Thin film solar panel test bed Demonstrate low drag finless architecture with active control Autonomous daytime station keeping Demonstrate small scale operations from non dedicated facility Applied engineering research tool Only COTS materials with existing tooling and facilities 5
Graf Galileo Day/Night Station Keeper (DNSK) 320 feet long 1 million cubic feet displacement GVW 5500 lbs. Li-Ion Batteries Brushless DC motors Incremental ramp up in size and capability Will test all required technologies for production units Test bed for propeller, solar panels, batteries, motors, fuel cells. Demonstrate Day/Night Station Keeping Can be built with COTS technologies 6
Graf Galileo One 640 feet long 8.1 million cubic feet displacement GVW 39k lbs. Li-Ion Batteries 4000 lb/20kwe payload Will be platform for 24/7 station keeping for 4000 lb, 20kWe sensor package Multiple airships for load-leveling Can be built with COTS technologies 7
Graf Galileo Two 830 feet long 17.6 million cubic feet GVW 93k lb 12k lb/75 kwe payload Nearly 18 million cubic feet- may be shunk significantly with battery or fuel cell technology improvements Will provide 24/7 platform for 12k lb, 75kWe sensor platform Can be built with COTS technologies 8
Graf Galileo Architecture Pressure stabilized hull and central airboom with catenary curtain baselined midway through SBIR phase one. Thrust vectoring, Fore and Aft propellers thrust vectoring front tractor for stability fixed stern propulsion for efficiency All ships can be built in a facility significantly smaller than the ship itself Assembly, check out and launch operations can take place from non-dedicated location 9
Graf Galileo Architecture, cont. High use of COTS architecture Operation-Centric concept and design Thin film solar and moderate energy density electrical batteries are the enabling technologies Low drag Finless design lower propulsion power required reduced battery mass 10
Graf Galileo Key Technologies Low permeation lifting gas cells High efficiency electrical motors Lightweight power storage Lightweight solar power Active control Central air boom High-efficiency Large-span propellers Robust design and operations plan Lift bags instead of ballonets to support 14:1 volume change 11
Low Permeation Lifting Gas Cells Completely sealed, hydrogen filled co-extruded Vectran/PPS membranes. No valves, saves weight, complexity, reduces failure modes Preliminary results have promise Galileo Systems has successful experience with GH 2 lifting gas 12
Gas Cell Diffusion / Leak Rate Vectran Liquid Crystal Polymer material- strong candidate 1/4000 th as Permeable as polyethylene 412ksi Tensile Strength Low Creep (Essentially Zero) Possible Metal Cladding (Aluminized Mylar) Make-Up Gas or Ballast Not Needed. 13
High Efficiency Electric Motors Brushless Efficiency greater than 90% demonstrated Light weight Long service life Similar to technology used on Pathfinder and Centurion long endurance aircraft 14
Power options Nuclear not considered Beamed power not considered All chemical not practical Thin film solar panels available from numerous vendors 15
Lay Out of Electrical System Typical Electrical Power Generation and Storage System Thin film Solar Panel 1 kwe/14 lb Step up/down Maximum Power Tracker with communications 0.2 kg DC Power bus 480V Step Up/Down Charge/Discharge Regulator w/ Comm Shunt Reg Controller Load Commercial Li-Ion Battery 15V @ 11A-h, 1.4 kg 16
Position of Electrical Components Thin Film Solar Panels MPP Tracker & DC Converter Power Bus 14AWG Loop VFD Drive & Motor Payload & Inverter Intelligent Battery 17
Hydrogen as a Lifting Gas Used widely in outside USA for stratospheric ballooning with good safety record. Higher performance than Helium Lower permeation than Helium Completely sealed architecture eliminates H 2 /air mixing Helium is a viable choice with attendant size/weight/ cost growth penalty 18
Drag Reduction Active Control permits Finless Hull lower radar cross section Radar Transparent Hull can eliminate gondola (internal payload carry) Stern Propulsion reduces drag through boundary layer control >40% drag reduction 19
Central Air boom, Air Pressure Stabilized Hull Enabling technology for ship assembly in nondedicated facility Damage and degradation tolerant Central air boom allows lower ship pressure and reduction or elimination of nose battens Active pressure control permits rigidity at all altitudes and built in test Low drag shape maintained at all altitudes (built in test) 20
Large Span Propellers Only appropriate for bow and stern propulsion architectures Enable extremely high propulsive efficiencies. Rutan-style lightweight construction technique hollow graphite/epoxy center spar thermal cut foam core graphite/epoxy overwrap 21
Stability and Control Inherently stable in roll and pitch Slightly unstable in yaw -- requires active control TORQUE TORQUE TORQUE Thrust Asymmetry Wind Shadow Blimp Body Airfoil Effects 22
Stability and Control Day Flier Actuator Requirements: Two Actuators: Tractor Pitch and Tractor Yaw Peak Power <3 Watts per axis Peak Force <0.33 lbs. per axis Linear Range ~3 cm ~5% duty cycle for worst-case station keeping Time Average Power Consumption <0.3 Watts Requires 10 cm lever arm from propeller hub 23
Stability and Control Day Flier Maneuverability Controller Type Tractor Fan Gimbal Rate Tractor Fan Gimbal Max Time to complete 3.6 o maneuver Time to complete 180 o maneuver Mild 1 deg/sec 4 deg 256 sec 550 sec Aggressive 10 deg/sec 15 deg 125 sec 245 sec Physical Limit 500 deg/sec 90 deg 9 sec 60 sec 24
Open Issues Thermal control Ozone Component longevity Hull stretch 25
Thermal control HAAs are unique in that they are a power-rich platform. Maintaining component temperatures can be conducted through waste-heat management. Detailed analysis required, payload characteristics needed Blowers, Heaters, and Albedo 26
Ozone and Ultraviolet build a little, fly a little may be best approach. Address ozone compatibility problems as they are identified in medium duration test flights. Alternate thin Stainless Steel Solar Panels Possible Metal Vapor Deposition 27
Component Longevity Engineering Data Bench Testing In situ results from incrementally gained flight test experience in HAA environment 28
Hull Stretch Selected materials are different from pressure airship materials of the 1920 s-1950 s. Techniques for dealing with stretch may be similar Air inflated architecture is tolerant to significant levels of stretch. Stretch is proportional to stress level, Graf Galileos are not highly stressed 29
Airship Innovation Significant, ~50% drag reduction through elimination of fins and external propulsion cars Example: Graf Galileo versus Conventional Airship Graf Galileo Day Night Station Keeper finless: 320 feet long (1M ft 3 ) 5400 lb. Conventional: 550 feet long (5M ft 3 ) 28,000 lb. Graf Galileo Two finless: 830 feet long (17.6M ft 3 ) 92,000 lb. Conventional: 970 feet long (28M ft 3 ) 150,000 lb. 30
Robust Design and Operations Plan PI has manufactured balloons >100,000 cubic feet in a 600 square foot work space successful flight to over 106k ft Graf Galileo operations plan leveraged from experience with extreme high altitude balloons FAA airspace coordination Impressive cost savings versus traditional blimp hangar option. 31
Typical Build up and Launch Step One: unroll hull (with integrated catenary curtain and central airboom) (The textile portions of the Graf Galileo DNSK are projected to be approximately 750 lbs., manageable by 10-12 workers without specialized tools) Step Two: Install batteries into keel (DNSK: 2800 lbs. batteries) Step Three: Inflate central airboom, mechanically install motors 32
Typical Build up and Launch, cont. Step Four: install and check out payload Step Five: Install lifting gas cells Step Six: Mechanically and Electrically integrate Solar panels Step Seven: Stake Down Hull, Inflate hull with air 33
Typical Build up and Launch, cont. Step Eight: attach propeller blades and check out propulsion system 34
Typical Build up and Launch, cont. Step Nine: load buoyancy gas into lifting gas cells 35
Typical Build up and Launch, cont. Step Ten: Untether ship and fly to service vicinity 36
End of Phase I Jan 13- Feb 8 Additional Engineering of Day Flier, Day/Night Station Keeper Continued Experiments (Fabrication Rates) Parts List Selection / Costing Phase II Proposal 37
Phase 2 Conduct detailed design, fabrication and test flights of Graf Galileo Day Flier. First flight within 4 months of contract start. Allowing for any technology improvements, proceed to detailed design, fabrication and test flights of Graf Galileo DNSK component parts prices are an issue Small, skunk works -like team with extensive design, build experience 38
Graf Galileo family of HAA vehicles K. Mark Caviezel, Engineer, PI Dr. Gary E. Snyder, President Richard Powers, Engineer Wil McCarthy, Engineer 39