Preliminary Design Review California State University, Long Beach - PowerPoint PPT Presentation

Preliminary Design Review California State University, Long Beach USLI November 13th, 2017

System Overview

Launch Vehicle Dimensions • Total Length 108in • Airframe OD 6.17in. ID 6.00in. • Couplers OD 5.998in. ID 5.775in. • Motor Mount 75mm • Centering Ring Thickness 0.2 in

Material Selection - Airframe, Nose Cone & Couplers Fiberglass • Significantly stronger than blue tube • Much cheaper than carbon fiber • More environmentally resistant than blue tube • Low thermal and electrical conductivity

Material Selection - Fins Carbon Fiber • Highest yield strength • Highest strength to weight • Great environmental resistance • Affordable for fins

Material Selection - Bulkheads & Centering Rings Aluminum • Stronger than wood • Inexpensive • Easily manufactured • Adds stability to coupler sections

Material Selection - Miscellaneous • Avionics tray will be 3D printed using ABS material • Epoxy for fin and centering ring attachment is Aeropoxy Light epoxy

Motor Selection • 75mm Cesaroni 4263-L1350-CS • Provides sufficient thrust to reach an apogee well over a mile

Stability • From the tip of the nose cone • Center of Gravity (CG)=68.73in • Center of Pressure (CP)=85.05in • Stability Margin=(85.05-68.73)/6.17in=2.64 cal

Flight Simulations • Total Mass-42.0lbs • Projected Apogee- 5467 ft • Thrust-to-weight ratio-7.21 • Velocity off rod -66.9ft/s

Recovery System Altimeter Vendor Model Cost Weight Features Integration Total (1-5) (1-5) (1-5) (1-5) Eggtimer Eggtimer 5 5 1 2 13 Quark PerfectFlite Stratologger 4 4 3 4 15 CF MissileWor RCC2+ 4 4 3 3 14 ks MissileWor RCC3 Sport 3 2 4 4 13 ks Adept AltS2-50k 2 2 2 3 9 Altus Easy Mega 1 3 5 4 13 Metrum

Recovery System (cont.) GPS Unit Comparison Vendor Model Cost Weight Dimensions Integration Total (1-5) (1-5) (1-5) (1-5) Transolve BeepX 5 2 1 2 10 Eggtimer Eggfinder 4 4 1 2 11 BigRedBe BRB900 3 4 3 4 14 e TX/RX Altus TeleMetrum 3 4 3 3 13 Metrum Altus TeleMega 2 4 1 4 11 Metrum

Recovery System (cont.) • 13” Coupler Piece • U-Bolt - 1,075 lb Maximum Capacity (Nylon Harness) • Primary and Backup Altimeters • BRB900 GPS Tracker • Rotary Switch

Recovery System (cont.) Type of Parachute Size and Model Location Relative Descent Velocity (fps) Parachute Drogue 20" FC TARC Low and Mid Power Nose Cone + Payload Bay Aft 92.99 Parachute Parachute End Main Parachute 84" FC Iris Ultra Standard Parachute Propulsion Bay Forward End 17.80

Recovery System (cont.) Wind Speed Wind Speed (fps) Drogue Main Drift (ft) Total Drift (ft) (mph) Drift (ft) 0 0 0 0 0 5 7.33335 376.958952 205.9929775 582.9519301 6 10 14.6667 753.917905 411.985955 1165.90386 2 15 22.00005 1130.87685 617.9789326 1748.85579 8 20 29.3334 1507.83581 823.9719101 2331.80772

Recovery System (cont.) Kinetic Energy for Each Independent Section Upon Landing Section Weight (lb) Mass (slugs) Descent Velocity (ft/s) Kinetic Energy (lb-ft) Payload Bay 13.879 0.431373199 17.80 68.3381421 9 Avionics Bay (After 4.769 0.148225289 17.80 23.4818502 Event 2) 8 Propulsion Bay 12.983 0.403524623 17.80 63.9263707 8

Recovery System (cont.)

Rover

Rover Overview • Ground clearance • Payload Space • Distance • Solar panel

Rover: Design Considerations • Cylindrical Rover • Stability, complexity, volume efficiency • Triangular • Able to deploy in multiple orientations. • More possibilities of failure. • Rectangular • Wheg wheels • Simple design

Rover: Design Choice • Triangular • Able to deploy from any orientation. • Bogie system • Gearbox

Rover: Design Choice • Triangular • Maximizes available space in rocket. • Houses all electronics inside the body.

Rover Controls and Electronics • Controller • Arduino Nano • Motorshield • Sensors • Inertial Measurement Unit (IMU) • Rangefinder • Control • Yaw Suppression • Obstacle Avoidance

Rover Deployment Mechanism (RDM)

RDM Summary Purpose: Remotely deploy the rover from the internal structure of the launch vehicle. Design Choice: ● Single motor ● One threaded rod and two non-threaded rods ● Load is driven along threaded rod through a matching threaded nut

Mechanical/Hardware ● Rotary to linear system for load translation ○ Motor attached to threaded rod ○ Threaded nuts attached to the rover ● Bulkhead with threaded nut

Electronics/ Control ● Remotely activate the system ○ 2.4GHz Digital Transmitter/Receiver ● Motor control ○ Arduino Nano Microcontroller ○ L298N H-Bridge ○ 11.1 V LiPo Battery ● Provide motor feedback ○ rotary encoder

RDM Schematics Remote rover Electric motor spins the Rocket lands deployment threaded rod in the switch initiated loosening direction The rover continues to translate, The nose cone translates and pushes the nose cone away along the rod and from the airframe. detaches. The rover falls off the rod and initializes the system.

Airbrake Summary • Main Goal: Ensure that the rocket achieves target apogee by correcting upward drift velocity after engine cutout. • Mechanics: airbrake flaps are deployed by use of a linear actuator. • Control: triggering the actuation of the flaps to maintain target velocity.

Airbrake mechanics • A linear actuator with a 2” stroke will be used to deploy the flaps from the rocket. • The actuator will pull up causing the linkage arms to straighten, deploying the flaps. • 4 flaps are used to maximize drag without compromising the structural integrity of the rocket.

Air Brake Control • Electronics • 2” Stroke electric linear actuator • Arduino Nano microcontroller • Sensors • Pitot Tube Airspeed Sensor • BMP280 Barometer • 6 DOF IMU • Control • Correct for error in velocity • Modeling of system to determine timing, duration, and deflection of flaps • Closed versus open-loop system

Significant Failure Mode - Launch Vehicle ● Tail Fins shear off during flight ○ Fins are not properly secured to airframe ○ Rocket takes unpredictable flight path ○ Ensure adhesive used is strong enough to handle force of flight. Check adhesive for cracks before launch. ● Fins not properly aligned ○ Fins not assembled correctly ○ Rocket spins uncontrollably ○ Follow proper procedure when assembling fins ● Motor centering ring fails ○ Adhesive not properly applied to centring ring ○ Motor launch through the rocket ○ Construction procedures are followed for applying adhesive

Significant Failure Mode - Recovery ● Parachute does not deploy ○ Parachute gets tangled around rocket ○ Rocket will fall to ground at high velocity ○ Parachute will be integrated in a was to reduce risk of getting tangled ● Parachute has rip ○ Parachute gets ripped while deploying ○ Rocket descend to quick and get damaged upon impact ○ Team members will be careful during packaging of parachute ● Altimeter failure ○ Faultily altimeter ○ Parachute will not deploy ○ Use two altimeter for redundancy

Significant Failure Mode - Airbrakes ● Structural damage to airbrake system during launch ○ Material of airbrake not strong enough ○ Airbrakes will not deploy or become damaged ○ Verify through testing that airbrake can handle force of flight ● Airbrakes do not deploy at desired altitude ○ Programming failure ○ Rocket will not make desired altitude ○ Test airbrakes programming during subscale launch ● Airbrake flaps fly off during flight ○ Flaps made not to handle force of launch ○ Rocket become unstable ○ Verify through testing flaps can handle force of flight

Significant Failure Mode - Rover ● Rover damaged during landing ○ Impact of landing more than expected ○ Rover becomes inoperable ○ Make sure rover is secure in place before launch and test to ensure it can handle force of landing ● Rover damaged during flight ○ Rover not secure in place ○ Rover becomes damaged and inoperable ○ Ensure rover is secure put in the rocket ● Rover gets stuck on rock ○ Rover not capable of handling terrain ○ Rover gets stuck and unable to make distance requirement ○ Design rover to handle all terrains and verify that through testing

Significant Failure Mode - RDM ● RDM does not deploy when activated ○ Programing failure ○ Rover will not deploy ○ Verify that programing will act as desired through testing ● RDM deploys during flight ○ Electronic failure ○ Nose cone opens up during flight ○ Ensure electronics work properly through testing ● RDM becomes damaged during flight ○ RDM materials cannot handle force of launch ○ RDM damaged and rover will not deploy ○ Choose strong material that can handle the force of flight