Launch Vehicle Propulsion Payload Recovery
Vehicle Dimensions Total length of inches 4.0” Airframe (3.9” Inside diameter) Fin span of 3.91” Separates into three sections Top Nosecone Payload Vertical Wind Turbine Middle Drogue Parachute Piston Altimeters Bottom Main Parachute Motor (Plugged) Fins
Materials- Airframe Entirely BlueTube 2.0 Heat and Humidity Resistant Lightweight compared to alternatives ProductSample LengthWeightWeight per inch Blue Tube3" x 48" x.062 wall577.9 grams12.04 grams per inch Plain phenolic3" x 48" x.062 wall423.9 grams8.83 grams per inch Glassed phenolic 3" x 48" x.062 wall868.8 grams18.1 grams per inch Filament wound fg 3" x 48" x.062 wall907.2 grams18.9 grams per inch Source: Alwaysreadyrocketry.com
Materials- Airframe Exceptionally strong material Vulcanized paper fiber with water resistant resin Tubing was “a component inside a warhead of the 155mm Howitzer, and 105mm Abrams Tank ordinance” –Always Ready Rocketry Is expected to withstand forces of launch
Materials- Airframe Maximum load of 3079 lbf (3 inch tube) Peak Stress of 5076 psi (3 inch tube) Impact resistant Source: Apogeerockets.com Source: Alwaysreadyrocketry.com
Materials- Fins Fins –Composite board with hardwood edging –Fiberglass outer layer –Honeycomb Nomex composite inside –Must have edging to airfoil Photos from GiantLeapRocketry.com
One-Third the weight of G10 Fiberglass Retains rigidity Airfoil edging will be of birch plywood Surface will be scored with hobby knife and drilled into to increase surface area Through-the-Wall assembly to the motor mounting Materials- Fins
Materials- Epoxy Loctite 30 minute Epoxy –All motor mounting and internal parts –Allows for absorption time –Less brittle, stronger bond Loctite 5 minute Epoxy –Fin Fillets
Bulkheads & Centering Rings 4-ply birch plates Each 3/16” thick All rings and bulkheads will be double thick Overall stronger plate More surface area to glue to
Materials- Other Vertical mounting boards –1/4” to 3/8”plywood –Used in payload and electronics bay Nose cone –Impact resistant plastic Tail cone –Urethane tail cone from Public Missiles to reduce drag
Stability Margin Stability margin of 2.01 calipers before launch Fins will be constructed last Fin size will be adjusted to keep this value
Stability Analysis 2.01 stability margin will allow for error Small drag forces from: –Nosecone screws –Solar panel’s edge –Pressure bleed off holes –Miscellaneous Margin will rise to 3.35 calipers after burnout
Vehicle Safety Verification Sub-scale launch Dec. 11 th (backup Dec. 18 th ) – Verifies stability and altimeter setup Strength tests on fins and bulkheads Heat, humidity, and warp testing – Oven, freezer – Soak in water First full scale launch in early February with dummy payload
Construction Safety All personnel trained to use power tools Two people working on a part minimum Gloves, aprons, and goggles during construction Masks when products with fumes are used –Epoxy –Paint
Launch Vehicle Propulsion Payload Recovery
Motor Selection Aerotech K700W Plugged forward closure MotorManufacturer Total Impulse (N- sec) Max Thrust (lbs) Burn Time (s) Average Thrust (lbs) Max Rocket Dry Weight* (lbs) K1050AeroTech K660Cesaroni K750Cesaroni K700AeroTech K828AeroTech K570Cesaroni K635Cesaroni * For rocket to reach 5,000 feet AGL Current projected dry mass = 15.4 lbs Will have room for error
Motor Selection Propellant from Giant Leap Rocketry Hardware from Apogee Rockets –AeroTech RMS-54/2560 casing –Plugged forward closure –Eyebolt threads for solid parachute mounting point Source: Apogeerockets.com
Thrust to Weight Ratio Thrust to weight = 6.81 to 1 with current plan Acceleration of 364 ft/s 2 on Launch –11.3 G’s Rail Exit Velocity = ft/s
Thrust Curve Source: ThrustCurve.com
Plan for Motor Safety Verification Inspect for any cracks or dents on casing Certified personnel assemble motor –George or Jack Sprague (Mentors) Inspect assembly Aerotech K700 motor is not a prototype and has been launched before
Launch Vehicle Propulsion Payload Recovery
Baseline Payload Design Measures voltage and current output of a flexible solar panel Observe changes in the strength of the Earth’s Magnetic Field LabPro Data logger records from all sensors simultaneously Accelerometer triggers data recording Data stored inside rocket, until retrieval
Payload Design- Structure Housed in the Modular Payload System (MPS) Three compartments Sensors secured with metal strapping All plywood Stainless steel support rods
Data Logging System LabPro Data Logger from Vernier Programmed to start taking data when accelerometer reads 7 G’s of acceleration Longer pad stay time, can take many readings from just ascent and descent Supplies power to all sensors Lithium AA batteries for reliable power source
Solar Panel System Solar Panel, current probe, voltage probe, resistors, and data logger Voltage probe in parallel around a 10 ohm resistor 30 ohm resistor in series to burn off voltage for sensors Current probe in series Solar panel leads go through airframe to sensors
Solar Panel
Flexible Solar Panel Two donated by FlexSolarCells.com for experiment
Magnetic Field System Vernier magnetic field sensor Isolated from all other electronics to reduce risk of interference Will measure a peak voltage when sensor points to magnetic South Rocket must spin so that we know it points South at some time
Magnetic Field Probe Field strength across the globe varies from 3.1 x to 5.4 x Teslas Typical variance in 25 nano Teslas on a given day in one location
Vertical Wind Turbine Magnetic Field sensor reads peak when pointed at magnetic south Catches horizontal wind and causes the rocket to spin
Significance Solar power is becoming cheaper and easier to integrate Viability of flexible solar on objects where direct sunlight is not always possible Magnetic field experiment could be used in the future for detailed data on the changes in the Earth’s magnetic field
Plan for Payload Verification System ground testing –Set up all sensors and record sample data –Will onboard electronics interfere with magnetic field sensor? Strength test components of MPS for the amount of G-forces it will go through Double check that systems working before launch Use new batteries before every launch
Launch Vehicle Propulsion Payload Recovery
Baseline Recovery System Design 24” TAC-1 Drogue Parachute at apogee –Backup ejection 2 seconds after apogee 84” TAC-1 Main Parachute at 700 feet –Backup ejection at 500 feet Swivels on each parachute Perfectflite MiniAlt/WD and HiAlt45K altimeters Radio transmitter for locating the rocket after landing
Recovery System Shock cord is 9/16” wide nylon strap –2000# rated –26’ on drogue 20’ on main Quick-Links for easier chute packing and repairs (if needed) U-Bolt parachute mounts Altimeter ejections have been staggered –Reduce risk of over-pressurizing airframe
Engine Burnout Primary Drogue Chute Ejection (at apogee) Backup Drogue Chute Ejection (2 sec after apogee) Primary Main Chute Ejection (700 feet) Backup Main Chute Ejection (500 feet) Flight Events and Ejections
Electronics Bay Each altimeter will have its own 9V battery and arming switch All connections will be secure so that no circuit breaks occur
Plan for Recovery Safety Verification Ejection charge ground tests in January Verify descent velocities with Rocksim Verify vertical wind turbine does not tangle cords 2000 lbs rated heavy-duty 9/16” nylon shock cord Altimeter testing in a vacuum chamber Verify function of radio transmitter in a ground test Use ohm meter to check ejection canisters before installing into rocket
Questions?