Rocket Based Deployable Data NetworkUniversity of New Hampshire Rocket CatsCollin Huston, Brian Gray, Joe Paulo, Shane Hedlund,

Sheldon McKinley, Fred Meissner, Cameron Borgal

2012-2013 Critical Design ReportSubmission Deadline: January 14, 2013

Overview• Objective• Launch Vehicle Dimensions• Key Design Features• Motor Selection• Mass Statement and Mass Margin• Stability Margin• Recovery Systems• Kinetic Energy• Predicted Drift• Test Plans and Procedures• Payload Integration• Interfaces

Objective

• The UNH Rocket Cats aim to create a Rocket Based Deployable Data Network (RBDDN). The objective is to design a low cost data network that can be deployed rapidly over a large area utilizing rockets.

Launch Vehicle DimensionsVehicle Dimensions• 71.31” in length• 4.014” Outer Diameter• 10.014” Span Diameter

Key Design Features

• Nose cone can be remotely deployed by the team on the ground

• One way bulkhead prevents the main parachute from being deployed when the nose cone is deployed

• The primary payload creates a Rapidly Deployable Data Network that allows wireless communication between devices

Motor Selection• Cesaroni Technology Inc. K940-WT Reloadable Motor

• Total Length: 15.9 in

• Diameter: 2.13 in

• Launch Mass: 48.2 oz.

• Total Impulse: 1636 Ns

• Average Thrust: 936 N

• Maximum Thrust: 1116 N

• Burn Time: 1.75 seconds

• Thrust to weight ratio: 13.5:1

• Exit Rail Velocity: 53.1 ft/s

Mass StatementVehicle Weight

Component Mass (oz.)

Nose Cone 7.196Payload 1 (Deploy) 49.6

Fuselage Tubing 24.557Bulkhead 1 3.8

Eject. Charges (3) 3.738Main Parachute 1

Main Shock Cord 3.54

OWB 6.32Bulkhead 2 2

Avionics 23.84Bulkhead 3 2.6

Drouge Parachute 0.41Drouge Shock Cord 3.44

Bulkhead 4 4.88Payload 2 (Fixed) 29.62

Bulkhead 5 3.55

FWD Centering Ring 0.416

AFT Centering Ring 0.416

54mm MMT 7.57

Fins (4) 8.96Motor 54.71

Tube Coupler 8

Launch Lug (2) 1

Shear pins (4) 0.035

Fire Blankets (3) 3.79

Total 254.988

Stability Margin

• Static Stability Margin– 1.81 calibers

• Center of Pressure– 55.048” from the nose tip

• Center of Gravity– 47.768” from the nose tip

Recovery Systems

Section Parachute Choice

Area [ Velocity [ Kinetic Energy [ft*lbf]

Drogue Public Missile Works PAR-30

4.91 .75 54.80 600.34

Payload Public Missile Works PAR-24

3.14 .8 35.64 65.5

Main Sky Angle 36 14.2 1.34 20.56 61.6

• Flat Nylon recovery harness

Kinetic Energy

• KE = • The kinetic energy values shown are

calculated from the chosen parachutes for the rocket

Section Parachute Choice

Velocity (ft/s) Kinetic Energy (ft*lbf)

Drogue Public Missile Works PAR-30

54.8 600.34

Payload Public Missile Works PAR-24

35.64 65.5

Main Sky Angle 36 20.56 61.6

Predicted DriftWind Speed [mph] Estimated Drift [ft]

0 8

5 440

10 850

15 1300

20 1800

Wind Speed [mph] Estimated Drift [ft]

0 8

5 440

10 1041

15 1862

20 2483

Vehicle

Deployed Payload

Vehicle Testing and ProceduresFunction Testing ProcedureOne-way Bulkhead/Main Parachute The one-way bulkhead can be ground

tested by prepping the rocket and ejecting the main parachute.

Nose cone The nose-cone can be ground tested by being ejected from the payload section of the rocket.

Drogue Parachute The drogue parachute can be ground tested by ejecting and separating the booster section from the payload section of the rocket.

Strength Testing/Integrity Using ejection charge testing to identify structural flaws, then reinforcing needed areas.

Scale Model Flight Test

• Successful exit from rails and drogue deployment

• Altimeter was switched off after drogue deployment

• The battery holder shorted the capacitor for the timer circuit

• The main parachute was never deployed

Tests of the Staged Recovery System• Testing showed that

revision of the one-way bulkhead was needed

One-way bulkhead testing procedure. One-way bulkhead

Successful nose cone deployment. Successful main parachute deployment.

Payload Design Overview• Primary payload– Deployed payload in nosecone– Atmospheric and GPS sensor data– Transmit and store sensor data

• Secondary payload– GPS sensor data– Act as node in network, transmit, and receive relevant data

Primary Payload Components

• Arduino Nano– Barometer: BMP085– Humidity and Temperature: SHT15, Cantherm MF51-

E thermistor– Ambient Light: PDV-P9200– Ultraviolet: PC10-2-TO5

• Raspberry Pi• GPS: GlobalSat BU-353• Xbee 900 Pro

Secondary Payload Components

• Raspberry Pi• GPS: GlobalSat BU-353• Xbee 900 Pro

Payload Testing and Procedures

•Battery–Test runtime under full payload power load–Use results to choose final battery packs

•Antenna–Test maximum transmission distance–Test antenna position in rocket–Test local EMI sources and positioning in payload

Payload Integration

• Sled containing primary payload is secured in nosecone using external bolts

• Sled containing secondary payload is secured in rocket body using a direct threaded connection

Interfaces

• Primary payload connects to recovery system via direct wired connection

• Communication to ground station and deployed nodes via Xbee 900mHz connection

• Avionics are isolated in separate bay• 1” Launch rails

Conclusion• Objective• Launch Vehicle Dimensions• Key Design Features• Motor Selection• Mass Statement and Mass Margin• Stability Margin• Recovery Systems• Kinetic Energy• Predicted Drift• Test Plans and Procedures• Payload Integration• Interfaces

Questions?