Project SCOTTIE: Preliminary Design Review Carnegie Mellon Rocket - - PowerPoint PPT Presentation

Project SCOTTIE: Preliminary Design Review

Carnegie Mellon Rocket Command November 14, 2018

Table of Contents

1. Vehicle Overview ……………………………………………………………………………………………… 2. Apogee Targeting System …………………………………………………………………………………. 3. Recovery Subsystem ………………………………………………………………………………………... 4. Mission Performance Predictions ……………................................................................ 5. Payload Overview ……………………………………................................................................. 6. Requirements Compliance Plan ………………................................................................. 7. Logistics …………………………………………………………………………………………………………….. 2 12 19 29 37 45 49 1

Table of Contents

1. Vehicle Overview …………………………………………………………………………………………… 2. Apogee Targeting System …………………………………………………………………………………. 3. Recovery Subsystem ………………………………………………………………………………………... 4. Mission Performance Predictions ……………................................................................ 5. Payload Overview ……………………………………................................................................. 6. Requirements Compliance Plan ………………................................................................. 7. Logistics …………………………………………………………………………………………………………….. 2 2 12 19 29 37 45 49

Launch Vehicle Overview

3

General Dimensions

Component Dimensions Mass (lb) Nose Cone 6” D x 24” L 2.08 Payload Bay 6” D x 10” L 4.11 Upper Airframe 6” D x 24” L 7.00 Recovery Bay 6” D x 6” L 2.98 Middle Airframe 6” D x 17” L 2.81 ATS Bay 6” D x 10” L 4.24 Lower Airframe 6” D x 35” L 10.94 Total 6” D x 115” L 33.8 (Dry), 41.7 (Wet)

4

Airframe

Material Cost Density (oz/in3)

• Ult. Tensile

Strength (ksi) Stiffness (msi) G-12 Fiberglass $3.80 1.23 60-80 5-10 Carbon Fiber $8.90 0.90 240 20-30 G12 Fiberglass Carbon Fiber

5

Nose Cone

Ratio Shape Weight Size Apogee Cd Cost Total Weight 10% 10% 10% 5% 28% 27% 10% 100% MC Ogive 3:1 w/ tip 1 4 3.6 5 3.9 4.9 1 3.625 MC Ogive 4:1 w/tip 4.7 4 2.7 3.2 2.2 5 1 3.366 PM Ogive 4:1 w/o tip 4.7 4 5 3.2 5 1.5 4.3 3.765 MC Ogive 5:1 w/o tip 4.8 4 4.2 1.8 4.9 1.3 5 3.613 AR Ogive 5:1 w/o tip 4.8 4 4.1 1.8 4.9 1.3 3.8 3.483

6

Nose Cone Top Choices

1.Public Missiles 4:1 Ogive

• Apogee = 6080.7’
• Drag Coefficient = 1.271
• Weight = 28 oz

2) Madcow 3:1 Ogive w/ AL tip

• Apogee = 5881.7’
• Drag Coefficient = 0.535
• Weight = 46.7 oz

3) Madcow 5:1 Ogive

• Apogee = 5978.5’
• Drag Coefficient = 1.3019
• Weight = 36 oz

7

Fin Planform Trade Study

Fin Planform Stability Coefficient of drag Strength Trapezoidal 8 8 8 Elliptical 8 5 9 Clipped Delta 9 8 6

8

Fin Cross Section Trade Study

Fin Cross Sections ANSYS Mesh Cross Section CD (avg) CL (avg) CL/CD (avg) Manuf. Ease Cost Rectangular 0.019 0.110 5.583 1 1 Rounded 0.008 0.056 6.588 5 2 Bevel 0.011 0.082 9.252 3 3 Airfoil 0.013 0.096 9.676 10 10

9

Leading Fin Design

• Four fins
• Trapezoidal planform
• 40 degree bevel cross section
• G10 Fiberglass
• 3/16” Thick
• Fin flutter
• Flutter velocity - 2909 ft/s
• Max velocity - 396 ft/s

10

Motor Retention System

Component

Motor Retainer Cap and Base Thrust Plate Bought In House Bought In House

Price

$55.56 $100 - 8”x8”x1.5” 6061-T651 Al $65.05 $24.93 - 8”x8”x0.5” 6061-T651 Al

Mechanical Feasibility

Easy Feasible (3 axis CNC mill) Easy Easy (3 axis CNC mill) Motor Retainer Thrust Plate

11

Table of Contents

1. Vehicle Overview ……………………………………………………………………………………………… 2. Apogee Targeting System ………………………………………………………………………………. 3. Recovery Subsystem ………………………………………………………………………………………... 4. Mission Performance Predictions ……………................................................................ 5. Payload Overview ……………………………………................................................................. 6. Requirements Compliance Plan ………………................................................................. 7. Logistics …………………………………………………………………………………………………………….. 12 2 12 19 29 37 45 49

Apogee Targeting System

• Prediction and Control Design
• ATS Electronics Bay Design
• Flap Design
• Flap Actuation System

13

Prediction and Control Overview

• R denotes target apogee
• X(v) denotes current state of the rocket
• Xp(v-dv) denotes prediction of X(v)

14

Prediction and Control Response

15

ATS Electronics Bay

• Pi Control

○

Raspberry Pi, motor driver, motor (stepper

• r servo), battery (7.4V LiPo)
• Modular Control

○

shares central controller, battery modules, and coprocessor, and IMU’s with payload deployment 16

Flap Design

Solid Rectangular Fin:

• Highest drag force in

subsonic region

• Rated to hold +30lb of

drag force Gridded Rectangular Fin:

• Comparable drag to solid

fins in subsonic region

• Rated to hold +30 lbs of

drag force Pin Flap:

• Rated to hold ~20

lbs of drag force

• Least drag force in

subsonic region 17

Flap Actuation

• Central turnpiece extends and retracts flaps through pin joint arms
• Supports and guides for flaps epoxied to bulkhead (attached to rocket shell)

○

Coated with teflon tape to reduce friction

• Bulkhead, arms, central turnpiece all made of aluminum (CNC routed)

18

Table of Contents

1. Vehicle Overview ……………………………………………………………………………………………… 2. Apogee Targeting System …………………………………………………………………………………. 3. Recovery Subsystem ……………………………………………………………………………………... 4. Mission Performance Predictions ……………................................................................ 5. Payload Overview ……………………………………................................................................. 6. Requirements Compliance Plan ………………................................................................. 7. Logistics …………………………………………………………………………………………………………….. 19 2 12 19 29 37 45 49

Recovery Subsystem

20

Recovery Bay

• Dimensions
• Length: 5”
• Mass: 21 oz
• Key Features
• 3D printed battery case and cover
• Rotary switch standoffs
• Bulkhead-like sled
• Coupler coated in aluminum tape for RF

shielding

• Benefits over Additive Aerospace Sled
• More compact
• More adaptable
• Better wire management

21

• 3D printed
• Attaches to bulkhead by screws
• Wires protrude through holes in the side and

battery clips go on through holes in the front

• Easily assembled and reusable
• Easy to manufacture
• Will fit on virtually any sled design
• 3D printed
• Attaches to bulkhead by screws
• A sure secure fit
• Allows for the reuse of rotary switches
• Easy to manufacture and assemble

Batteries and Switches Cases

Battery Case Switch Case 22

Altimeters

Altimeter Price Dimensions Weight Altitude Accuracy Operating Voltage PerfectFlite Stratologger CF $58.80 2"L, 0.85"W, 0.5"H 0.38 oz ± 0.1% 9V nominal (4V to 16V) Missile Works RRC2+ $44.95 2.28"L, 0.925"W, ~0.5"H 0.35 oz Not given 9V(3.5VDC- 10VDC) Missile Works RRC3 $79.95 3.92"L, 0.925"W, 0.563"H

• 0. 59 oz

Not given 9V(3.5VDC- 10VDC)

23

• Location
• Fixed to middle airframe, below the recovery bay
• Provide easy access to turn on while on launch pad
• Components
• 3D printed custom housing module
• Eggfinder Tracking System
• OpenLog data logger
• Power Stick
• LiPo battery pack

GPS

24

Electronics Wiring

• Two redundant systems
• Each have own battery
• Each have own switch
• Drogue charges
• Primary: Apogee +1s
• Backup: Apogee + 2s
• Main charges
• Primary: 550 ft
• Backup: 500 ft

25

Main Parachute Options

SkyAngle CERT-3 XXL

• Canopy with panels
• High Cd
• Large packing volume
• Moderately expensive

Fruity Chute Iris Ultra 84”

• Toroidal
• High Cd
• Small packing volume
• Very Expensive

RocketMan 14 ft

• Canopy with panels
• Moderate Cd
• High packing volume
• Inexpensive

26

Main Parachute Selection

Parachute Name Area (ft

2)

Cd A*Cd (ft

2)

Cost CERT-3 XXLarge 59.87 2.92 174.81 $239 Iris Ultra 120” 76.11 2.200 167.44 $402 Rocketman 14 ft 201.06 0.770 156.85 $155

27

Drogue Parachute Selection

Chosen SkyAngle Classic II 32”

• Provides descent time less than 90 seconds
• Max acceleration of main opening is less than 1000 ft/s^2
• Packing volume fits within airframe
• Economical price
• Asymmetric design induces rotation during descent

28

Table of Contents

1. Vehicle Overview ……………………………………………………………………………………………… 2. Apogee Targeting System …………………………………………………………………………………. 3. Recovery Subsystem ………………………………………………………………………………………... 4. Mission Performance Predictions ……………............................................................ 5. Payload Overview ……………………………………................................................................. 6. Requirements Compliance Plan ………………................................................................. 7. Logistics …………………………………………………………………………………………………………….. 29 2 12 19 29 37 45 49

Apogee Targeting Proceedure

Target Apogee: 5100 ft Methodology

• Select motor that achieves apogee 5300 ft – 6000 ft
• Apply ballast so that apogee is reduced to 5300 ft
• Use ATS to apply drag and fine tune altitude to 5100 ft

30

Motor Selection

Motor Peak Thrust (lbf) Average Thrust (lbf) Total Impulse (lbf –s) Duration (s) Apogee Range (ft) CTI L1350 376 303 958.4 3.2 5400- 5600 AeroTech L1420 408 319 1035 3.2 5750-5950

31

Flight Profile for CTI L1350

32

Flight Profile for CTI L1350, Max Ballast

Parameter Value Apogee (ft) 5079 Thrust to Weight Ratio 7.28 Rail Exit Velocity (ft/s) 78.7 Maximum Velocity (ft/s) 594 Landing Velocity (ft/s) 13 Descent Time 89.4

33

Drift Calculations

𝑈ℎ𝑓𝑝𝑠𝑓𝑢𝑗𝑑𝑏𝑚 𝐸𝑠𝑗𝑔𝑢 = 𝑢𝐸𝑤 𝑢𝐸 = 89.4 𝑡 𝑤 = 𝑥𝑗𝑜𝑒 𝑡𝑞𝑓𝑓𝑒

Wind Speed Open Rocket Predicted Drift Theoretical Predicted Drift 1198 5 1320 657 10 1568 1314 15 1823 1971 20 2152 2628

34

Kinetic Energy

Section Mass (oz) Kinetic Energy (lbf-ft) Upper Section 99.13 17.72 Middle Section 199.70 35.70 Lower Section 313.40 56.03 Total 612.23 N/A

𝐿𝐹 = 1 2 𝑛𝑊2 𝑊 = 2𝑛𝑕 ρ𝐵𝐷𝐸

Middle Section Upper Section Lower Section

35

Stability

Case Stability Margin (cal) CG Location (in from tip) CP Location (in from tip) No Motor 3.33 68.596 89.114 CTI L1350, min ballast (0 oz) 2.20 75.541 89.114 CTI L1350, max ballast (31.75 oz) 2.73 72.284 89.114 AeroTech L1420, min ballast (16.5 oz) 2.20 75.541 89.114 AeroTech L1420, max ballast (65 oz) 2.94 71.004 89.114

36

Table of Contents

1. Vehicle Overview ……………………………………………………………………………………………… 2. Apogee Targeting System …………………………………………………………………………………. 3. Recovery Subsystem ………………………………………………………………………………………... 4. Mission Performance Predictions ……………................................................................ 5. Payload Overview …………………………………................................................................. 6. Requirements Compliance Plan ………………................................................................. 7. Logistics …………………………………………………………………………………………………………….. 37 2 12 19 29 37 45 49

Payload

38

Payload UAV Design Options

Fixed-Wing 40 Rolling Cage Quadcopter Folding Quadcopter 39

Payload UAV Design Options

41 Design Weight Position Control Size Efficiency Crash Recovery Cost Fixed Wing Low Poor Large High Poor Low Rolling Cage Quad High Fine Moderate Low High High Folding Quad Medium Fine Small Moderate Poor Moderate 40

Ground Control Communication

• Spektrum DX8 Radio (UAV Control)
• Multi-frequency Video Receiver Ground Station
• Redundant Links Provide Video Failover
• Video Streamed From Ground Station to Video Goggles (FPV Goggles)

42 41

Beacon Drop

• Micro Linear Servos provide

actuation

• Extremely light servo (1.5g)

increases range

• “Hook” locks beacon into place
• Beacon remains locked in place

even without power

• Beacon provides counterweight for

drone in cage

• When over the FEA, release beacon

43 42

Payload Deployment System

• Stepper motor shafts connect

to lead screws via couplings.

• Lead screws actuate piston

head and upper bulkhead via lead nuts that are epoxied to these.

• Lead screws have high

mechanical advantage

• Piston head pushes UAV out
• f payload bay.
• Differential encoders on

stepper motors allow for feedback control. 44

Upper Airframe Nosecone

43

UAV Securing Mechanism

• Round-tipped connectors mated to either end of the UAV

shaft work in tandem with un-threaded collars on the front and aft faces of the mesh to keep the UAV secure within the payload bay. 45 44

Table of Contents

1. Vehicle Overview ……………………………………………………………………………………………… 2. Apogee Targeting System …………………………………………………………………………………. 3. Recovery Subsystem ………………………………………………………………………………………... 4. Mission Performance Predictions ……………................................................................ 5. Payload Overview ……………………………………................................................................. 6. Requirements Compliance Plan ………………............................................................. 7. Logistics …………………………………………………………………………………………………………….. 45 2 12 19 29 37 45 49

Vehicle Requirements

NASA Subsection NASA Requirement Report Explanation Report Subsection 2.2 Teams shall identify their target altitude goal at the PDR milestone. The declared target altitude will be used to determine the team’s altitude score during Launch Week. Apogee goal is 5100 ft. Section 3.3.2 Req. Number Requirement Verification Method Verification Status 2 The launch vehicle will not exceed 50 lbs. Analysis: OpenRocket will be used to model the rocket and all of the internal

• subsystems. This will produce a weight estimate.

Inspection: All components will be weighed using a digital scale in order to determine accurate weights for the Open Rocket model. Met

NASA Specified Team Derived 46

Recovery System Requirements

NASA Subsection NASA Requirement Report Explanation Report Subsection 3.12.1 The recovery system altimeters will be physically located in a separate compartment within the vehicle from any other radio frequency transmitting device and/or magnetic wave producing device. The recovery bay will be separated from the GPS, which will be housed in an isolated container affixed to the inside of the airframe. Section 3.2.4 Req. Number Requirement Verification Method Verification Status 1 The maximum acceleration of the rocket will not exceed 1000 ft/s2. This will ensure a factor of safety of 2 on the shock cords. Analysis: Open Rocket flight simulations will provide the acceleration during flight, including the sharp increase in acceleration when the main parachute

• deploys. The maximum acceleration predicted by a nominal flight

simulation will be used for our factor of safety calculation on the shock cord. Met

NASA Specified Team Derived 47

Payload Requirements

NASA Subsection NASA Requirement Report Explanation Report Subsection 4.4.2 The UAV will be powered off until the rocket has safely landed on the ground and is capable of being powered

• n remotely after landing.

UAV will be placed into a low power state with the motors turned off during the duration of

• flight. It will only be activated by a remote signal

sent by the team with the permission of the RSO. Section 5.1 Req. Number Requirement Verification Method Verification Status 1 The UAV must fly from landing site to the tarp with 30% battery remaining Real world prototype testing where the pilot with fly on a designated course (of a specific distance) to measure distance flown until 30%

• battery. That distance must be at least 1.5 times the average distance

from the tarp to the land site In progress

NASA Specified Team Derived 48

Table of Contents

1. Vehicle Overview ……………………………………………………………………………………………… 2. Apogee Targeting System …………………………………………………………………………………. 3. Recovery Subsystem ………………………………………………………………………………………... 4. Mission Performance Predictions ……………................................................................ 5. Payload Overview ……………………………………................................................................. 6. Requirements Compliance Plan ………………................................................................. 7. Logistics ……….………………………………….………………………………………………………………. 49 2 12 19 29 37 45 49

Budget

Category Amount Percent Total Travel $3,890.00 34.7 Launch Vehicles $3,323.78 29.7 Payload $2,065.00 18.4 Avionics $1,053.92 9.4 Recovery $475.23 4.2 Reserve $400.00 3.6 Total $11,207.93 100.0 $3,890 $3,324 $2,065 $1,054 $476 $400 Travel Launch Vehicles Payload Avionics Recovery Reserve

50

Funding

Category Amount Percent Total Allocated Budget $5,837 34.7 Crowdfunding $5,000 29.7 CMU College of Engineering $2,500 14.8 CMU Mech. Eng. $1,000 5.9 Drone Club $750 4.5 Member Dues $750 4.5 CMU Physics $500 3.0 Sponsorships $500 3.0 Total $16,837 100.0 $5,837 $5,000 $2,500 $1,000 $750 $750 $500 $500 Allocated Budget Crowdfunding CMU College of Engineering CMU Mech. Eng. Drone Club Member Dues CMU Physics Sponsorships

51

Educational Engagement

15 75 60 45 25 200

YMCA Burrel/Huston School Environmental Charter School CMU Children's School CMU Homecoming

47 10 143

CMU Children's School CMU Homecoming Remaining

52

Project Timeline – Past

53

Project Timeline - Future

54

Project Timeline - Completion

55

Questions?