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

• Significantly stronger than blue tube

• Much cheaper than carbon fiber

• More environmentally resistant than blue tube

• Low thermal and electrical conductivity

Fiberglass

Material Selection - Fins

Carbon Fiber

• Highest yield strength

• Highest strength to weight

• Great environmental

resistance

• Affordable for fins

Material Selection - Bulkheads & Centering Rings

• Stronger than wood

• Inexpensive

• Easily manufactured

• Adds stability to coupler

sections

Aluminum

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 SystemAltimeter

Vendor Model Cost (1-5)

Weight (1-5)

Features (1-5)

Integration (1-5)

Total

Eggtimer Eggtimer Quark

5 5 1 2 13

PerfectFlite Stratologger CF

4 4 3 4 15

MissileWorks

RCC2+ 4 4 3 3 14

MissileWorks

RCC3 Sport 3 2 4 4 13

Adept AltS2-50k 2 2 2 3 9

Altus Metrum

Easy Mega 1 3 5 4 13

Recovery System (cont.)GPS Unit Comparison

Vendor Model Cost (1-5)

Weight (1-5)

Dimensions (1-5)

Integration (1-5)

Total

Transolve BeepX 5 2 1 2 10

Eggtimer Eggfinder 4 4 1 2 11

BigRedBee

BRB900 TX/RX

3 4 3 4 14

Altus Metrum

TeleMetrum 3 4 3 3 13

Altus Metrum

TeleMega 2 4 1 4 11

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

Parachute Size and Model Location Relative Descent Velocity (fps)

Drogue Parachute

20" FC TARC Low and Mid Power Parachute

Nose Cone + Payload Bay Aft End

92.99

Main Parachute 84" FC Iris Ultra Standard Parachute Propulsion Bay Forward End 17.80

Recovery System (cont.)

Wind Speed (mph)

Wind Speed (fps) Drogue Drift (ft)

Main Drift (ft) Total Drift (ft)

0 0 0 0 0

5 7.33335 376.9589526

205.9929775 582.9519301

10 14.6667 753.9179052

411.985955 1165.90386

15 22.00005 1130.876858

617.9789326 1748.85579

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 68.33814219

Avionics Bay (After Event 2)

4.769 0.148225289 17.80 23.48185028

Propulsion Bay 12.983 0.403524623 17.80 63.92637078

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 SummaryPurpose: 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 deployment switch initiated

Rocket landsElectric motor spins the threaded rod in the loosening direction

The nose cone translates along the rod and detaches.

The rover continues to translate, and pushes the nose cone away from the airframe.

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

Testing

● Wind tunnel○ Test drag force and drag coefficient of airbrake flaps

● Drop testing○ Test strength of components to ensure they can

handle forces of flight and landing● Programing and Electronic testing

○ Test all programs and electronics to ensure that they act in the way that they are supposed to

● Shock and Impact testing○ Test all components of launch vehicle to ensure that

they can handle the shock of the flight and the impact of landing

Project Plan

TimelineSubscale Launch in November, Full scale built by February, Full scale launch in March

Airbrake Timeline

Educational Engagement

Event Date Estimated Attendees

Girls Day at the Beach (1) 3/2017 100

Aerospace Rocket Symposium

9/7/2017 200

Girls Day at the Beach (2) 9/2017 200

Introduction to Engineering Presentations

11/2017 100

MAES Latinos in Engineering Bottle Rocketry

4/2018 60

High School Engineering Presentation

12/2018 500

TOTAL 1160

Budget-ExpensesSubteam Projected Expenses

RDM $178.84

Rover $553.58

Avionics $538.63

Recovery $517.10

Launch Vehicle $2,295

Airbrake $137.83

Business $8,670

Total $13,870.91

Budget-Income

Source Income

College of Engineering $4,200

AIAA - CSULB $1,500

Fundraisers $1,500

ASI Travel Grant $7,000

Sponserships $600

Total $14,800