RockSat-C 2012PDR

Team NamePreliminary Design Review

University/InstitutionTeam Members

Date

1

RockSat-C 2012PDR

User Notes

• You can reformat this to fit your design, but be sure to cover at least the information requested on the following slides

• This template contains all of the information you are required to convey at the PDR level. If you have questions, please don’t hesitate to contact me directly:

rocksatprogram@gmail.com 720-314-3552

2

RockSat-C 2012PDR

User Notes

• This template is based on an example mission to show the level of detail needed for your “preliminary design”

3

RockSat-C 2012PDR

Purpose of PDR

• Confirm that:– Science objectives and required

system performance have been translated into verifiable requirements

– Payload Design: to specifications from requirements, can be met through proposed design (trade studies)

– Project risks have been identified, and mitigation plans exist

– Project management plan is adequate to meet schedule and budget

– Project is at a level to proceed to prototyping of high risk items

4

gnurf.net

RockSat-C 2012PDR

PDR Presentation Content

5

• Section 1: Mission Overview– Mission Overview– Organizational Chart– Theory and Concepts– Concept of Operations– Expected Results

• Section 2: System Overview– Subsystem Definitions– Critical Interfaces (ICDs?)– System Level Block Diagram– System/Project Level Requirement Verification Plan– User Guide Compliance– Sharing Logistics

RockSat-C 2012PDR

PDR Presentation Contents

• Section 3: Subsystem Design– Subsystem A (SSA) (i.e. EPS)

• SSA Block Diagram• SSA Key Trade Studies (1 – 2?)• Subsystem Risk Matrix/Mitigation

– Subsystem B (SSB) (i.e. STR)• SSA Block Diagram• SSA Key Trade Studies (1 – 2?)• Subsystem Risk Matrix/Mitigation

– Etc., Etc…

6

jessicaswanson.com

RockSat-C 2012PDR

PDR Presentation Contents

• Section 4: Prototyping Plan– Item “A” to be Prototyped– Item “B” to be Prototyped– Etc., Etc…

• Section 5: Project Management Plan– User’s Guide Compliance, Sharing– Org Chart– Schedule– Work Breakdown Structure– Budget

7

RockSat-C 2012PDR

Mission OverviewName of Presenter

8

RockSat-C 2012PDR

Mission Overview

• Mission statement• Break mission statement down into

your overall mission requirements• What do you expect to discover or

prove?• Who will this benefit/what will your

data be used for?

9

RockSat-C 2012PDR

Theory and Concepts

• Give a brief overview of the underlying science concepts and theory

• What other research has been performed in the past?– Results?

10

RockSat-C 2012PDR

Concept of Operations

• Based on science objectives, diagram of what the payload will be doing during flight, highlights areas of interest

• Example on following slide

11

RockSat-C 2012PDR

Example ConOps

t ≈ 1.3 min

Altitude: 75 km

Event A Occurs

t ≈ 15 min

Splash Down

t ≈ 1.7 min

Altitude: 95 km

Event B Occurs

-G switch triggered

-All systems on

-Begin data collection

t = 0 min

t ≈ 4.0 min

Altitude: 95 km

Event C OccursApogee

t ≈ 2.8 min

Altitude: ≈115 km

End of Orion Burn

t ≈ 0.6 min

Altitude: 52 km

t ≈ 4.5 min

Altitude: 75 km

Event D Occurs

Altitude

t ≈ 5.5 min

Chute Deploys

RockSat-C 2012PDR

Expected Results

13

• This is vital in showing you understand the science concepts

• Go over what you expect to find– Ex. What wavelengths do you expect to

see? How many particles do you expect to measure? How well do you expect the spin stabilizer to work (settling time?)? How many counts of radiation? etc

RockSat-C 2012PDR

System OverviewName of Presenter

14

RockSat-C 2012PDR

System Level Block Diagram

15

Buck Converter

Boost Converter

uController

WFF P

ower

InterfaceW

FF Telem.

Interface

Motor Controller

EPS

DEPPM

Photomultiplier

STR

Wallops PT

Interfaces

Low Voltage

High Voltage

Data/Control

Legend

• Show a full system of your subsystems, and the connections between them

RockSat-C 2012PDR

System Design – Physical Model

16

MEPO Board

AVR Board G-Switch

Battery

Accelerometer

DetectorWFF Door Piece

Mounting Flange

RockSat-C 2012PDR

That was a BAD PHYSICAL MODEL!

• Why? Because you must have DIMENSIONS and UNITS!

• Remember, this is a preliminary design, so the design doesn’t have to be perfect or final– But still have labels, dimensions, and

units

17

RockSat-C 2012PDR

Design in Canister (preliminary)

18

Where are the dimensions?!

RockSat-C 2012PDR

System Concept of Operations

• Here, include a diagram and a step by step of your data collection process, or major activities happening in your payload– If you are collecting data, show/discuss

when the data will be available, how it’s collected, and where it gets sent

– If you have moving parts, be sure to include a simplified timeline of how things are happening along with the data collection

• This slide must be included

19

RockSat-C 2012PDR

Critical Interfaces

20

• At the PDR level you should at minimum identify critical interfaces. The following is an example of types of interfaces you might have, and how the interface between two systems might be designedInterface Name Brief Description Potential Solution

EPS/STRThe electrical power system boards will need to mount to the RockSat-X deck to fix them rigidly to the launch vehicle. The connection should be sufficient to survive 20Gs in the thrust axis and 10 Gs in the lateral axes. Buckling is a key failure mode.

Heritage shows that stainless steel or aluminum stand-offs work well. Sizes and numbers required will be determined by CDR.

PM/STRThe photomultiplier will need to mount to the RockSat-X deck rigidly. The connection should be sufficient to survive 20Gs in the thrust axis and 10 Gs in the lateral axes. Most likely, the PM will hang, and the supports will be in tension.

A spring and damper support will need to be developed. The system should decrease the overall amplitude of vibration no less than 50%.

DEP/STRThe deployment mechanism must rigidly connect to the RockSat-X deck. The actuator has pre-drilled and tapped 8-32 mounts.

8-32 cap head screws will mount the deployment mechanism to the plate. The screws will come through the bottom of the plate to mate with the DEP system.

DEP/EPSThe deployment mechanism has a standard, male RS-232 DB-9 connector to interface to a motor controller (male), which is provided with the DEP mechanism. The motor controller will be controlled by EPS.

A standard, serial cable with female DB-9 connector on both ends will connect the motor controller to the DEP mechanism. The motor controller to EPS system interface is yet to be determined.

PM/EPSThe photomultiplier requires 800V DC and outputs pulses at TTL levels. The PM also requires a ground connection.

A TBD 2 pin power connector (insulated) will connect the EPS board to the PM. A separate, TBD connector will transmit the pulse train to the asynchronous line at a TBD Baud rate.

RockSat-C 2012PDR

Requirement Verification

• At the PDR level, highlight the most critical project/system requirements and determine how you will VERIFY these requirements– This starts the process of test planning

• Verification: did you build the thing right?– Validation: did you build the right thing – we

won’t focus too much on validation, because it is more of a customer consideration

21

RockSat-C 2012PDR

Requirement Verification Example Table

22

Requirement Verification Method DescriptionThey deploable boom shall deploy to a height of no more than 12”

Demonstration Boom will be expanded to full length in the upright position to verify it doesn’t exceed 12”

The boom shall extend to the full 12” height in less than 5 seconds from a horizontal position.

Analysis The system’s dynamical characteristics will be derived from SolidWorks, and available torques will yield minimum response time.

The full system shall fit on a single RockSat-X deck

Inspection Visual inspection will verify this requirement

The sytem shall survive the vibration characteristics prescribed by the RockSat-X program.

Test The system will be subjected to these vibration loads in June during testing week.

RockSat-C 2012PDR

Why do we care about requirements?

• At this point, I will be checking to make sure you have a good set of requirements to define your project

• This comic is an entertaining, but accurate, depiction of what can happen with a project that is not well defined, managed, and documented

23

http://www.codinghorror.com/blog/2005/03/on-software-engineering.html

RockSat-C 2012PDR

Subsystem DesignName of Subsystem

*You will have several subsystems*

Name of Presenter

24

RockSat-C 2012PDR

Subsystem Design Section

• This section is where you explain how each subsystem was designed

• Discuss how you researched components that would meet your requirements– Show trade studies if necessary, and if you

show them, be prepared to explain the scoring and categories

• The most important part is explaining how you reached your major design decisions in each subsystem

• After explaining components, discuss any risks associated with this subsystem

25

RockSat-C 2012PDR

Subsystem Overview – Block Diagram• Show your subsystems, now with more detail inside

the boxes, and the connections between them

26

RockSat-C 2012PDR

EPS: Block Diagram

27

• Show the subsystem block diagram with primary component choices highlighted.

Power

Data/Control

Legend

RockSat-C 2012PDR

EPS: Trade Studies

28

• Show rationale for you choices in components. You basically weigh your options against your requirements and what each component can offer. Don’t forget things like: availability, cost, and prior knowledge. I recommend an online search for examples if you are unsure, or contact me.µController XMega ATMega 32 L

Cost 8 10Availability 10 10

Clock Speed 10 5A/D Converters 9 5Programming

Language8 8

Average: 9 7.6

• You should have completed a trade study for each block, but you only need to present the 2-3 most important.

• Numbers are relatively subjective, but 10 should represent a perfect fit, 5 will work, but is not desirable, and 0 does NOT meet expectations.

• The component with the highest average should drive your choice for design.

RockSat-C 2012PDR

EPS: Risk Matrix

29

EPS.RSK.1: Mission objectives aren’t met IF microcontroller fails in-flightEPS.RSK.2: Mission objectives aren’t met IF a suitable motor controller cannot be procured EPS.RSK.3: The EPS system can’t survive launch conditions, and the mission objectives aren’t metEPS.RSK.4: A strain will be put on the power budget IF flying monkeys delay the launch by an hour

• Risks for the subsystem under discussion should be documented here

• The horizontal represents the likelihood of a risk, the vertical is the corresponding consequence.

• Risks placement should help drive mitigation priority

RockSat-C 2012PDR

Writing Risks – a note

• When you write a risk, you are writing about the bad thing that might result, NOT the cause– Ex: “Risk 1: There might be one+ month delay

in obtaining our science instrument” – not quite. This is the cause. The RISK is what this might do to your project, like delay testing, integration, schedule, etc, so you could write “Risk 1: The integration schedule will slip due to delays in procuring the science instrument”

30

RockSat-C 2012PDR

Prototyping PlanName of Presenter

31

RockSat-C 2012PDR

Prototyping Section

• The purpose of this section is to help you identify what components/connections might need testing before you can say with confidence that you want something in your final design

• Not everything must be prototyped (you don’t have time)

• Prototypes are usually used to address risks

32

RockSat-C 2012PDR

Prototyping Plan

33

Concern about mounting the PM to the deck has been

expressed (Risk: jeopardize the mission objectives)

STR

PM

DEP

EPS

Concerns about testing the PM on the ground have

been expressed

Mounting the probe to the end of the boom will present a

significant challenge

The functionality of the microcontoller board needs

to be verified by CDR

Prototype this interface and verify the fit with

the PM

Develop a test plan and verify it with LASP

mentors

Mount a test probe and verify structural rigidity

Prototype the micro board on a bread board

to verify functionality

Risk/Concern Action

• What will you build/test between now and CDR to mitigate risks?

RockSat-C 2012PDR

Project Management PlanName of Presenter

34

RockSat-C 2012PDR

RockSat-C 2012 User’s Guide Compliance

35

• Rough Order of Magnitude mass estimate– Initial masses of major components,

sensors, structural pieces– Start thinking about BALLAST

• CG – predicted CG based on your design

• Are you using high voltage– How are the schematics/safety coming

along?• Are you using any ports? How will

you interface with them? Are you sharing an atmospheric port? – you may not know some of these at this time, which is fine

RockSat-C 2012PDR

Sharing Logistics – if applicable

36

• If known:• Who are you sharing with?

– Summary of your partner’s mission (1 line)

• Plan for collaboration– How do you communicate?– How will you share designs

(solidworks, any actual fit checks before next June)?

• Structural interface – will you be joining with standoffs or something else (again, be wary of clearance)?

grandpmr.com

RockSat-C 2012PDR

Organizational Chart

• Please turn your organization from CoDR into an official chart• What subsystems do you have?• Who works on each subsystem?

– Leads?• Don’t forget faculty advisor/sponsor(s)

37

Project ManagerShawn Carroll

System EngineerEmily Logan

CFOShawn Carroll

Faculty AdvisorChris Koehler

SponsorLASP

Faculty AdvisoryRiley Pack

Safety EngineerChris Koehler

Testing Lead Jessica Brown

EPSDavid Ferguson

Riley Pack

STRTyler Murphy

Aaron Russert

DEPAaron RussertShawn Carroll

PMKirstyn JohnsonElliott Richerson

RockSat-C 2012PDR

Schedule

38

• What are the major milestones for your project?• (i.e. when will things be prototyped?)• CDR• When will you begin procuring hardware?• Start thinking all the way to the end of the project!

• Rough integration and testing schedule in the spring• Etc, etc, etc

• Format:• Gant charts• Excel spreadsheet• Simple list• Whatever works for you! Don’t let the schedule

sneak up on you!

schedule

RockSat-C 2012PDR

WBS

39

• Present a very top-level work break down schedule• One can look up the tree for large scope goals• One can look down the tree for dependencies• Help each subsystem “see” the path ahead• Based on the schedule and requirements

PMP EPS STR PM DEP

•Obtain PM from LASP

•EEF Proposal for funding•…•…

•Trade Studies

•Schematics

•Schematic Review

•ICDs

•First Revision of Boards

•…•…

•Trade Studies

•Order Materials

•Work Request Into Shop

•…•…

•Obtain PM from LASP

•EEF Proposal for funding

•…•…

•Obtain PM from LASP

•EEF Proposal for funding

•…•…

RockSat-C 2012PDR

Budget

40

• Present a very top-level budget (not nut and bolt level)• A simple Excel spreadsheet will do• Most important factor is LEAD TIME

• Simply to ensure that at this preliminary stage you aren’t over budget• It is suggested that you add in at least a 25% margin at this point

Margin: 0.25 Budget: $1,300.00 Last Update: 9/30/2010 11:50ExampleSat

Item Supplier Estimated, Specific Cost Number Required Toal Cost NotesMotor Controller DigiKey $150.00 2 $300.00 1 for testingPM LASP $0.00 1 $0.00 LASP mentor deserves shirtMicrocontroller DigiKey $18.00 3 $54.00 3 board revsPrinted Circuit Boards Advanced Circuits $33.00 3 $99.00 3 board revsMisc. Electronics (R,L,C) DigiKey $80.00 3 $240.00 3 board revsBoom Material onlinemetals.com $40.00 2 $80.00 1 test articleProbe LASP $0.00 1 $0.00 Testing Materials ??? $200.00 1 $200.00 Estimated cost to test system

Total (no margin): $973.00Total (w/ margin): $1,216.25

RockSat-C 2012PDR

• Summarize your main action items to get done before CDR

• Issues, concerns, any questions

Conclusion

41