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Zero TiltCritical Design Review

Frostburg State UniversityBrett Dugan, Adam Rexroad, Kaetie Combs, Michael Stevenson, Daniel Gares,

Mayowa Ogundipe, Tyler Lemmert, Jared Hughes, Sean Hughes, Andrew Huntley, Subhasis Ghosh, Derek Val-Addo,

11/27/2011

1

Mission Overview

2

Mission Statement: Zero Tilt’s goal is to provide, for the first time, a stable environment throughout the flight of a Sounding Rocket via two concurrent objectives:

◦Tilt correction system

◦Despun platform system

3

Mission Overview

We plan to:

◦ Counteract the platform spin◦ Orient the platform parallel to the earth’s surface at all times◦ Confirm the altitude reading using an accelerometer on our

platform

We expect to prove that it is possible to correct spin, tilt, and determine the altitude based upon a level reference.

This could benefit any scientific experiment that requires stabilization in order to collect data.

4

Mission Overview

The underlying theory and concepts:

◦negative feedback control systems ◦concepts of torque and centripetal force

◦Micro electromechanical systems (MEMS)

◦Real-Time Systems Theory (for multi-tasking)

5

Mission Overview: Theory and Concepts

Mission Objectives:

◦ Counter the spin of the rocket during flight.

◦ Keep a level surface to earth using our conceptual design.

◦ Prove successful by using the stored gyroscope output and the feedback from various motors.

Minimum success criteria

◦ Our main goals as the Zero Tilt team is to receive results indicating that we achieved zero tilt for the flight of a sounding rocket.

6

Mission Overview: Mission Requirements

7

Organizational Chart

Project ManagerKaetie Combs

MentorsAdam RexroadBrett Dugan

Faculty AdvisorDr. Mohammed Eltayeb

Despun PlatformDaniel Gares

Tyler LemmertKaetie Combs

Zero Tilt PlatformMichael Stevenson

Daniel GaresAndrew Huntley

SensorsKaetie CombsTyler Lemmert

Andrew HuntleyMichael Stevenson

Data SystemJared HughesSean Hughes

Mayowa OgundipeDerek Val-Addo

Breakdown of Sub-Systems

8

Despun Platform

Zero Tilt Platform

Data Systems

Sensors

Design:

Daniel GaresKaetie CombsTyler Lemmert

Gears:

Tyler Lemmert

Design:

Daniel GaresMike Stevenson Andrew Huntley

Everybody will be involved with programming.

Processors: Jared HughesSean Hughes

Motors:

Mayowa OgundipeVal-AddoSubhasis Ghosh

Accelerometers: Kaetie CombsTyler Lemmert

Gyroscope:

Mike StevensonAndrew Huntley

Zero Tilt Con-Ops

t ≈ 1.3 min Altitude: 75

km

t ≈ 15 min

Splash Down

t ≈ 1.7 min

Altitude: 95 km

-All systems on

-Initialize de-spun system

-Initialize zero tilt system based on low-G acceler –ometer value.

-Despun system prepares for initial spin up.

t = 0 min

t ≈ 4.0 min

Altitude: 95 kmApogee

t ≈ 2.8 min Altitude: ≈115 km

t ≈ 4.5 min

Altitude: 75 km

t ≈ 5.5 min

Chute Deploys

-use the position of the zero tilt plate as initial value for the gyroscope sensor.-switch to gyro input for zero tilt system.

What we expect:

◦ Using feedback analyze whether we were successful in despinning the platform. More than a one percent error in this section would provide too much error in the tilt system. Therefore we expect this system to perform near perfection.

◦ Determine whether we were successful in keeping our platform level. (within a plus or minus 5 degree envelope)

10

Expected Results

Design Description

11

12

The scope of the project has changed slightly.

◦ We no longer require a viewport for camera due to size constraints.

◦ There was a minor change made to the design which will be discussed in the Mechanical Design elements section.

◦ Due to processor obligations we will not be verifying the altitude with the Low-G accelerometer.

◦ Our method for obtaining power has changed since the 9 volt batteries we were considering do not supply the continuous current necessary. Instead we will use a combination of AA batteries and 9 volts to supply various systems with the correct power.

De-Scopes

13

If we run out of time or money, or main goal would become to concentrate on the despun system.

If the tilt system does not have the time to complete the tilt correction, we may have to institute a different system. Such as running two processors and two gyros, one for each motor.

If the intuition that the priority of motors in the tilt system is wrong, then we need to consider major program changes.

Off RAMPS

14

Mechanical Design

Mechanical Design Elements

Mechanical Design Elements – Gear Elements

16

Mechanical Design Elements – Main Gear

17

Main Gear 75 teeth 12 Diametral Pitch 6.25 inch Pitch Diameter Pitch Diameter based off design constraints

Mechanical Design Elements – Main Gear Calculations

18

Nomenclature Formula Calculation Measurement

Number of teeth (N) N=P*D N=12*6.25 75 teeth

Diametral Pitch (P) P=N/D P=75/6.25 12

Outside Diameter (Do) Do=(N+2)/P Do=(75+2)/12 6.4166 inches

Circular Pitch (p) p=(Pi*D)/N p=(Pi*6.25)/75 0.2618 inches

Addendum (a) a=1.000/p a=1.000/12 0.0833 inches

Dedendum (b) b=1.250/P b=1.250/12 0.1042 inches

Working Depth (hk) hk=2.000/P hk=2.000/12 0.1666 inches

Root Diameter (Dr) Dr=(N-2.5)/P Dr=(75-2.5)/12 6.0417 inches

     

20 degree pressure angle    

Gear Ratio (GR) GR=Nmain/NdriveGR=75teeth/

15teeth 5:1

Mechanical Design Elements – Drive Gear

19

Drive Gear15 teeth12 Diametral Pitch1.25 inch Pitch DiameterPitch Diameter based off strict

design thresholds

Mechanical Design Elements – Drive Gear Calculations

20

Nomenclature Formula Calculation Measurement

Number of teeth (N) N=P*D N=12*1.25 15 teeth

Diametral Pitch (P) P=N/D P=15/1.25 12

Outside Diameter (Do) Do=(N+2)/P Do=(15+2)/12 1.4166 inches

Circular Pitch (p) p=(Pi*D)/N p=(Pi*1.25)/15 0.2618 inches

Addendum (a) a=1.000/p a=1.000/12 0.0833 inches

Dedendum (b) b=1.250/P b=1.250/12 0.1042 inches

Working Depth (hk) hk=2.000/P hk=2.000/12 0.1666 inches

Root Diameter (Dr) Dr=(N-2.5)/P Dr=(15-2.5)/12 1.0417 inches

     

20 degree pressure angle    

Gear Ratio (GR) GR=Nmain/Ndrive GR=75teeth/15teeth 5:1

After cutting the gears, we will utilize one of the electric motors in the campus machine shop to test the durability and precision of the

With the electric motors we can test the durability of the gears by meshing them at high speeds as well as applying a load to the gears. With such testing we can find weak points as well as any points where destructive friction is present.

By testing the gears at max conditions, we will be assured that the gears will survive the ascent and splash-down.

Mechanical Design Elements – Gear Testing

21

Upper Center Shaft

Tilt Servo

Lower Center Shaft

Slip Ring

Top Plate

Spin Bearing

Tilt Bearing

Tilt Platform

Drive Motor Housing

Drive Motor

Spin Servo

Gimbal

Main Gear Bearing

Slip Ring Leads

Bottom Plate

Main Gear

Drive Gear

Support Posts

Shield

Circuit Board and Battery Placement

Tilt Platform Circuit Board

Side View

Side View

Side View

Top View

Wiring Diagram(shown by red dashed line)

Design Changes Since the PDR there has been one

crucial design change. The way the design was laid out, there was no way to get power to the spin servo located on the gear. This is shown by the blue arrows in the diagram. When the power source reached the bearing, an additional slip ring would be needed to cross the bearing. To fix this we switched the raised the drive gear and put the servo on top of the gimbal. The servo now can get power through the slip ring shown by the red arrows. The only down side to this, is the weight of the servo will have to be countered to prevent wobble in the system.

32

The support poles that we are using to hold up the weight of the capsule above us has been changed to a different material.

The old material was 7075 Aluminum. The new material is Carbon Fiber.

The reason we have made this decision is to reduce the weight of the capsule.

Design Changes (continued)

MaterialsPart Material Diamensions cost per unit quantity total Distributor Part #

support poles Carbon Fiber Di=0.414, Do=0.500, h=48 38.61 1 38.61 McMaster 2153T41

top plate 7075 Aluminum 12 X 12 X .125 42.17 1 42.17 McMaster 8885K15

base plate 7075 Aluminum D=10, 1 70.05 1 70.05 Speedymetals N/A

main gear 7075 Aluminum D=7, 1 38.34 1 38.34 Speedymetals N/A

gimbal 7075 Aluminum 3 X 4 X 7 97.58 1 97.58 Speedymetals N/A

drive gear 7075 Aluminum D-3 X 1 7.82 1 7.82 Speedymetals N/A

center shaft ABS D=2.5 X 12 38.85 1 38.85 McMaster 8587K31

platform fiberglass 6 X 3 X 1 57.91 1 57.91 McMaster 3345K26

servo gear 7075 Aluminum Made from base plate shaft excess 0 N/A N/A

Main Gear Bearing Steel Di=2, Do=2.5, T=.25 195.26 1 195.26 McMaster 6656K11

Spin Bearing Steel Di=2, Do=2.5, T=.25 195.26 1 195.26 McMaster 6656K11

Tilt Bearing Steel Di=1/4, Do=5/8, T=.196 17.46 1 17.46 McMaster 3826T17

Slip Ring N/A N/A 54.45 1 54.45 Mercotac 230

Shield 6061 Aluminum Di=6.5, Do=6, h=4 12.72 1 12.72 Speedymetals N/A

Order Total 866.48

34

Electrical Design

Please show finalized block diagrams, state how many PCBs/breadboards you will use and what each one will do, sensors they will have

Show the schematics for each PCB/bb◦ I know they will be large and difficult to see in detail but

I’m looking to see that they have been completed Any changes to this system since PDR?

◦ How does this affect your mission requirements?◦ What has been finalized that wasn’t at PDR?

Will you activate with command line or gswitch/LEDEX?◦ If command line, state how early you want to activate

and show the schematic you have derived to comply with the User’s Guide reqs

35

Electrical Design Elements

36

Schematics

Despun and Zero tilt on following slides

37

38

39

Software Design

40

Software Design Elements

Accelerometer 1

Accelerometer 2

Microcontroller

Power Supply

Digital to Analog

Converter

Slip Ring

Gyroscope Microcontroller

Motor

Servo φ

Servo θ

41

Initialization Flowchart

42

De-spun System FlowchartStart

Initialize Timer and all sub-systems

Start despun program

Merge

Measure despun accelerometer 1

Measure despun accelerometer 2

Value ≠ Last Value?

Value ≠ Last Value?

Write Latest to Memory

Write Latest to Memory

Yes Yes

Average values in memory

Adjust Motor0 RPM

No No

Program Time Limit Reached?

No No

End despun program

Yes

Power down all sub-systems

End

43

Zero-Tilt System Flowchart

43

StartInitialize Timer and

all sub-systems

Start Tilt program

Merge

Measure tilt gyroscope for x

and y

X Value ≠ Last X Value?

Y Value ≠ Last Y Value?

Write Latest to Memory

Write Latest to Memory

Yes Yes

No

No

Get Tilt Initialization Point

Start

Calculate Motor1 adjustment with x

from Memory relative to

initialization point

Calculate Motor2 adjustment with y

from Memory relative to

initialization point

Adjust Motor 1 Position

Adjust Motor 2 Position

Merge

Program Time Limit Reached?

End tilt program

Power down all sub-systems

End

Yes

No

44

Major Functions Timer – From system start: counts down from start to

calculated stop time, ending all programs, powering down systems at end.

Low-g accelerometer – Used at system start, before lift off, to orient tilt system with respect to gravity. Provides Initialization point.

High-g accelerometers – Major despun input, measures rocket rotational acceleration to be opposed equal and opposite to by platform.

Motor0 – Despun motor that rotates platform to cancel out rocket’s rotation.

45

Gyroscope – Major tilt input, measures tilt platform orientation with respect to x and y axis.

Motor 1 – Tilt motor (servo) rotates tilt platform from x axis measurements to keep tilt platform level relative to initialization point.

Motor 2 – Tilt motor (servo) rotates tilt platform from y axis measurements to keep tilt platform level relative to initialization point.

Major Functions (Continued)

Prototyping/Analysis

46

47

Altitude plot of past Rockon flight,analyzed on the following slide.

Latitude vs Longitude plot of past Rockon flight, anlayzed on the following slide.

Chute Deploys

48

What this data tells us about flight:

◦ Due to the Latitude vs Longitude plot we can conclude that the motor controlling the spin in the tilt system is of a low priority. This is because the maximum angle the rocket can change in the plane of concern is 45 degrees.

◦ The altitude plot demonstrates that the majority of the change in the tilt will occur at the apex. It must be able to rotate 180 degrees. This means that the tilt motor will have priority over the spin motor due to the greater degree in change over a shorter time period.

◦ As will be explained in the software section we believe our processer will be able to perform both the tilt and spin tasks without falling behind due to the small variations in spin coupled with the priority placed on tilt.

Analysis of Past Flight Data

49

The programming of our processor has made considerable strides with a demonstration of the PVM capabilities of the motor.

The Motor was controlled using the program provided on the following slides.

We now are assured we can control the servo motors (motors 1 and 2) and are working toward accomplishing similar goals with the despun motor (motor 0), and the sensors.

Analysis of Motor Demonstration

50

* Created: 11/13/2011 11:32:10 PM * Author: Mayowa & Derek */ //#define F_CPU 1000000 // If processor speed (or clock) changes, redefine

#include "inc.h“

#include <avr/io.h>

//#include <avr/interrupt.h> // include interrupt from compiler

#include <util/delay.h> // Include Delay Functions from compiler

Sample Code

51

int stop=67,forward=14,backward=128; // values at points corresponding to move motor 2 void M1_move(unsigned int pwm) // function call to move motor 2

{ OCR0 = pwm; // output compare register for timer 0

}

void motors_init() // initialization for timers

{

TCCR0 = 0x7A; // configure for fast inverted PWM output on motor control pins:

Sample Code (continued)

52

OCR0 = 67; // initialize all PWMs to 0% duty cycle; point where motor brakes DDRB |= (1 << PORTB3); // set PWM pins as digital outputs

}

void move_90ryt() // Test for 90 degree turn under no load

{

OCR0 = forward; // motor 2 moves clockwise

_delay_ms(262); // continue moving 262 ms

OCR0 = stop;

button_check: // Debounce implementation

Sample Code (continued)

53

if ((bit_is_set(PIND,PD3)))

{

return;}

Else

{goto button_check;

}

int main( ) // main program starts

{

Sample Code (continued)

54

motors_init(); // initialize pwm

while (1) // infinite loop

{

if (bit_is_clear(PIND,PD0)) // check for input on switch 0

{

M1_move(stop); // call for brake

}

if(bit_is_clear(PIND,PD1)) // check for input on switch 1

{

M1_move(forward); // call to move clockwise

}

Sample Code (continued)

55

if (bit_is_clear(PIND,PD2)) // check for input on switch 2

{

M1_move(backward); // call to move counterclockwise

}

if (bit_is_clear(PIND,PD3)) // check for input on switch 3

{

move_90ryt(); // call for 90 degree turn

}

}

}

Sample Code (continued)

56

Constructions of the size of various mechanical components.

◦ Acryllic board made to model the zero-tilt platform.

Clearance considerations Length by width comparisons to components Motor placement

◦ Metal half-capsule made for a visual idea of size constraints

Used to decide upon things to be included and those to be thrown out. Instrumental in the decision to abandon camera option.

Motor/Processor prototype to test controllability.

◦ Necessary to prove to ourselves that we could manipulate the servo motors effectively.

Prototyping Results

57

Mass and Power Allowances

Mass Budget

58

Weight Budget

Assembly 5.5lbs.

Container 3lbs.Fixed components 1lbs.

Total 9.5lbs.

Total allowed 10lbs

Under/Over 0.5lbs

59

Detailed Power Budget

Sub-System

Voltage (V)

Current (A)

Time (h)

Amp-Hours

Motor 0 24 2.59 0.25 0.6475

Plate 1 5.25 0.0035 0.25 0.000875

Plate 2 6 0.3173 0.25 0.079325

0.7277Total A*h

0.2723

UnderOver (A)

60

Power Requirements for Despun Motor

Description Load Source AA

Quantity 1 Quantity 32

Voltage (V) 24 Voltage 1.5

Current (mA) 2590 Continuous Current (mA) 2000

Power (mW) 62160 Current Capacity (mA) 3000

Time (H) 0.25 Time (H) 0.25

Energy (mW-H) 15540 Current Capacity (mA) 6000

Continuous Current Capacity (mA) 4000

Energy Capacity (mW-H) 96000

Needed: Available:

61

Analysis of Load Power (Needed)

Load

Description

Low G Acceler-ometer Gyroscope Processor

Motor 1

Motor 2

High G Acceler-ometer Processor Total Energy

Quantity 1 1 1 1 1 2 1

Voltage (V) 5.25 3 3 5 6 5.25 3Current

(mA) 1.1 6.1 1.1 189 120 2.9 1.1Power (mW) 5.775 18.3 3.3 945 720 15.225 3.3

Time (H) 0.25 0.25 0.25 0.25 0.25 0.25 0.25Energy (mW-H) 1.44375 4.575 0.825 236.3 180 7.6125 0.825 431.53125

62

Analysis of Load Power (available)

Source 9VQuantity 3Voltage (V) 9Continuous Current(mA) 150Current Capacity(mAh) 1200Time (H) 0.25Total Current Capacity (mA) 3600Total Continuous Current Capacity (mA) 450Energy Capacity (mW-H) 32400

Manufacturing Plan

63

Machining

The following part will need to be machined: upper center shaft, lower center shaft, top plate, bottom plate, gimbal, tilt platform, drive motor housing, main gear, drive gear, support posts, and shield. These parts will be machined in house.

The bearings will be ordered from Mcmaster-Carr. The slip ring will be ordered from Mercotac.

65

Despun System

Tilt System

Integration of both

Construction of Systems (Orally conveyed)

Electrical Elements

Needs To be manufactured

◦ PCB

◦ Soldered our self

AVR, speed controller, resister, capacitors, voltage regulators, diodes, header, and transistors

◦ Place on the PCB by the company

Flash, accelerometers, gyro

Realistically we envision at least 3 revisions of our designed layout but hope to have our finalized piece up to specifications for the company by the time listed in the schedule section.

Software Elements (Despun) The first block of code is the code read and

process data from the two high-G accelerometers.

The second block of code controls the despun motor and therefore depends upon the first block of code.

Software Elements (Zero Tilt) The first block of code in this system assumes

that the despun system worked properly. The low-G accelerometer code is used to initialize the system. The gyroscope code is used to maintain orientation during flight.

The second block of code depends on the readings from the gyroscope and the accelerometer. The motor code translates sensor data into the amount the motor needs to turn to maintain zero tilt.

Testing Plan

69

System Level Testing - Sensors Sensor output evaluation

◦ Understanding the sensor output◦ Test of real-time transfer of the data◦ Self test of each sensor

prove accuracy Assure workability

◦ Survivability test

The system passes if we maintain a steady data transfer

System Level Testing - Despun Despun test

◦ Use the machine shop lathe to spin at variable speeds.

Measures rotational force Assures platform compensates for spin

This test will be successful if Motor 0 keeps up with the spin.

System Level Testing - Tilt

Tilt test

◦ Test the system using a variety of orientations, the motors will compensate our influence.

The system passes testing if Motors 1 and 2 correct tilt properly, maintaining a maximum error of plus or minus 5 degrees.

◦ This will be the final test assuming all other systems perform perfectly!

Mechanical Testing – Stress Test

Complete system maximum stress test

◦ Method to be decided◦ We were thinking about dropping the unit from a

height and rebound the fall with bungee cords◦ This test will simulate the initial shock from the

launch

The unit passes the stress test if all systems and subsystems survive

Mechanical Testing – Force Test

Vibration and rotation test

Utilizes a shaker table and lathe

◦ De-spun platform test◦ Spin of gimbal test

Also we must insure the following:

◦ Remain under mass constraints of 10lbs◦ Remain under volume constraints of a 9.3in Diameter and 4.75in height.◦ Keep center of gravity within the 1 x 1 x 1in envelope

We’ll know the system passed if there is minimal wobble and the system doesn’t break apart during rotation

Mechanical Design Elements – Gear Testing

75

After cutting the gears, we will utilize one of the electric motors in the campus machine shop to test the durability and precision of the gears.

With the electric motors we can test the durability of the gears by meshing them at high speeds as well as applying a load to the gears. With such testing we can find weak points as well as any points where destructive friction is present.

By testing the gears at max conditions, we will be assured that the gears will survive the ascent and splash-down.

76

Evaluation Boards

◦ Test Gyroscope output, real time sample rate, accuracy, and power.

◦ Test the motor response, speed, and power consumption.

◦ Processor performance including speed, storage of data, and power.

◦ Test all Accelerometer output, and confirm power consumption.

If we can adequately supply power to our components, communicate between all of our devices, and accomplish the goals of our subsystems then we would call this a success.

Electrical Testing

77

After the evaluations have been completed as of the systems need to be integrated to make sure that they can be successfully supplied with power.

Finally, the electrical components need to be finalized in preparation for fabrication (PCB construction), this is when severe revisions will be performed.

Electrical Testing (continued)

78

Software determines how well our devices can communicate as well as the optimum speed. Therefore it is instrumental in our electrical system.

In order to test the accelerometers on the base plate we will need to read data, process the data into motor ready commands, and relay it to our despun motor: motor 0.

In order to test the gyroscope we will need code to read from the gyroscope, process this data, and relay it to the necessary motors: motor 1 and 2.

Software Testing

79

In order to test that we are storing data correctly, sections of code will need to be dedicated to transferring readings to the flash memory.

In order to test that we can initialize the zero tilt system correctly we must have code to use the Low-G accelerometer for initialization, then switch to Gyroscope control.

Finally, in order to assure zero tilt, our code must be able to prioritize tasks, such as what was discussed in the analysis section.

Software Testing (continued)

Risks

80

Risk Walk-Down (Main Risks from PDR)

81

Consequence

RSK.1- Despun System Fails

RSK.2- Power Failure

RSK.5-Communication

Failure

RSK.4- Tilt System Fails

RSK.3- Zero-tilt Fails to

Initialize

RSK.3- Mechanical

Flaw

Possibility

• What have we done to mitigate them?

• With a better understanding of the function-ability of our subsystems we were able to walk-down several of our risk factors.

• The most important was the Despun system (RSK.1). With a feedback system we are more confident that we can control the motors speed effectively.

Risk Walk-Down (Main Risks Now)

82

Consequence

RSK.1- Despun System Fails

RSK.2- Communication

Faliure

RSK.3- Mechanical

Flaw

Possibility

• Do we have plans to walk these down?

• Yes, we hope that we are able through testing to iron out any mechanical flaws or imperfections of material.

• In addition we hope to vigorously test the electrical components so that the risk of a communication failure becomes even less likely.

• Are there any risks you just have to accept?

• The risk we must accept is that our despun system fails. Hopefully with enough tests we can alleviate the possibility further.

User Guide Compliance

83

Mass – we verified that we are within the 10lb maximum in mass budget.

CG within 1”x1”x1” envelope? How have you checked this

◦ With the addition of batteries to our mechanical drawings we were able to verify that we could remain within a 0.5”x0.5”x0.5” envelope.

Batteries: We will be using a combination of 9V batteries and Lithium AA’s.

RESTATE: We plan to activate prior to launch and have changed our time after reviewing the allowable constraints. With a maximum of 10mins we would like to use a 9 minute initialization time.

84

User Guide Compliance

Sharing Logistics

85

We are sharing with Harding University

According to their PDR, their mission is to design, build, test and fly a spectrometer that will measure transmission spectra of gases in Earth’s atmosphere at lower altitudes and the Sun’s irradiance at higher altitudes.

Plan for collaboration:

◦ We intend to communicate with them via E-Mail. We have not communicated with Harding University as of yet because we only need to verify their mass in order for our stress testing. Thus, this communication is not of high priority at the moment. Also, looking at their PDR they said they sent us Design models but we have received nothing of the sort.

Structural interface – Our systems will be separated by a plate, however their capsule will screw into ours.

grandpmr.com

Project Management Plan

86

Schedule (From PDR)

87

Tentative Schedule

• Finalize Design

• Beginning of November: Start ordering parts

• Now until end of semester: Start testing electric components, test gyroscope output, test accelerometer outputs, test servo response, make sure we are able to supply necessary power, and complete despun subsystem.

• Next semester

• End of February: Zero Tilt platform completed• For the rest of the semester we will continue testing and

correcting problems to prepare for the launch in June.

Schedule- Schedule for the Rest of this Semester (Fall 2011)

December12/1 Critical Design Teleconference

12/1-12/12 Continue Testing Electrical Components, Accelerometer and Gyroscope Output, and Motor Response Acquire All Necessary Components for Project. Begin Machining of Mechanical Components so They are Prepared for the Spring Semester

12/12 Last Day of the Semester

Schedule (continued)- Schedule for Start of Next Semester (Spring 2012)

January1/25 First Day of the Semester

1/25-1/30 Prepare Progress Report 1 Fabricate and Begin Testing on De-spun System Begin Testing Tilt System Send Flash, Accelerometers and Gyroscopes to Company of Choice to be Placed on PCB Complete Sensor Output Evaluation

1/30-2/13 Test Individual Subsystems and Prepare Reports Finish Testing De-spun System Finish Testing Tilt System Conduct Stress, Force, and Gear Tests Ensure that Electrical Systems are Functioning Properly Verify that Code Performs as Expected Walk-Down Risk Factors

1/30 Progress Report 1 Due

February2/3 First Payment Due

2/13 Individual Subsystem Testing Reports Due 2/14 Individual Subsystem Testing Reports Teleconference

2/14-3/12 Prepare Progress Report 2

Schedule (continued)- Schedule for Middle of Next Semester (Spring 2012)

March3/12 Progress Report 2 Due

3/12-4/2 Work on Payload Subsystem Integration and Prepare Testing Reports

April4/2 Payload Subsystem Integration and Testing Report Due 4/3 Payload Subsystem Integration and Testing Report Teleconference 4/6 Final Payment Due

4/15 RockSat Payload Canisters Sent to Customers 4/15-4/16 Work on Placing Entire System in Canister for Testing 4/15-4/23 Simulate Mission and Prepare Test Report

4/23 First Full Mission Simulation Test Report Presentation Due 4/24 First Full Mission Simulation Test Report Presentation Teleconference

4/24-5/28 Continue Simulations and Testing and Prepare for Launch Readiness Review

Schedule (continued)- Schedule for End of Next Semester (Spring 2012)

May5/7 Weekly Teleconference 1

5/14 Weekly Teleconference 2 5/21 Weekly Teleconference 3 5/28 Launch Readiness Review Presentations 5/29 Launch Readiness Review Teleconference

June6/4 Weekly Teleconference 4

6/11 Weekly Teleconference 5 6/14 Visual Inspections at Refuge Inn

6/15-6/18 Integration/Vibration at Wallops 6/20 Presentation's to Next Year's Rock Sat 6/21 Launch Day

Budget         

  Budget  

  Status Item Quantity Unit price Total price  

  Received Processors 2 $5.20 $10.40  

  Received Evaluation Board (Processors) 1 $82.16 $82.16  

  Received Gyroscope 1 0 $0.00  

  Received Evaluation Board (Gyroscope) 1 $27.00 $27.00  

  Need to Buy Motor Controller 1 $5.00 $5.00  

  Need to Buy Motor 0 1 $365.00 $365.00  

  Need to Buy Motor 1 1 $8.92 $8.92  

  Already Have Motor 2 1 $0.00 $0.00  

  Ordered Accelerometer ADXL203 2 $27.95 $55.90  

  Ordered Accelerometer ADXL278 2 $33.83 $67.66  

  Need to Buy Materials See Next Slide See Next Slide $866.48  

         

  Total $1488.52  Total with Margin $1637.37

93

Issues we still have include:

◦ A viable test for the initial stress (takeoff).◦ Real-time functionality of the tilt system.◦ A steeper price for the raw materials then previously

anticipated.

The plan of action (before break):

◦ To acquire the remaining components.◦ Finish tests concerning the motors.◦ Begin testing of sensors using evaluation boards.◦ Evaluate price inflations.◦ Continue to walk-down our risk factors.

Conclusion


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