Skillz That KillzTeam 3

Conceptual Design Review

Travis Dowdy, Jocelyn Mulkey, Hunter Hoopes, Taylor Smith, Kaitlyn Zimmitti, Jess Davidoff

September 22, 2009

(Happy Fall!)

Mission Overview

• Investigate the benefit/cost of replacing batteries with solar panels to power future BalloonSat missions– Monitor the voltage intake from solar panels placed

on the payload and determine if it is enough to power future payloads

Predicted benefits:More volume within the structure for experimental equipmentIf steady predictable voltage available, experiments may not be constrained by battery life

Design

• 6 solar panels will be attached to the outside of the payload cube– One on each side– One on the top– One on the bottom

• To record voltage– Use one analogue for top panel– Use one for bottom panel– Use one for recording the 4 side panels

• To collect data from the four side panels we will• collect the ground wires from the four panels,• each other lead will be soldered to a circuit board at 90 degree points• a small motor with shaft will rotate an arm that makes contact with each panel point• that data will then be recorded.•

• The assumption is this• If the payload rotates, each reading should provide about the same average voltage reading over the course of the flight. • If the payload starts rotating and ends in a static condition, we should see several of the panel's data drop off and only one or two panels producing current. •

• If there is no or minimal rotation we should only see in the data two panels providing current.•

• The top and bottom panels may provide more power; it depends on the angle of the sun and the shadow cast by the balloon over the course of the flight. •

• The motor attatches to the gear reduction box. We will then need to build an “S” shaped piece (out of plastic or wood) that has a wire attached to it. The bottom of the “S” tracks across the circuit board hitting the four panel points. The other end of the wire is at the top of the shaft and must rub against a static piece of wire or copper that is connected to the analogue input.

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• Every item included in the payload has a trade off. If the top or bottom or (top and bottom) panels do not supply sufficient extra voltage with respect to their weight, it would not be worth it to replace batteries with solar panels placed at these positions on the cube. We would make the same conclusions about the panels on the sides of the payload.

Design– Parts– Drawings– Functional block diagram– The question of “HOW are you going to complete your mission?” should be answered

The solar panel we will use.

• How To Take Data From 4 Panels Using One Analogue Input– Collect ground wires from the panels

– The other leads will be soldered to circuit board at 90° points

– A small motor with a shaft will rotate an arm that makes contact with each panel point

– The data will be collected into one stream

• If the payload rotates, each reading should provide about the same average voltage reading over the course of the flight.

• If the payload starts rotating and ends in a static condition, we should see several of the panel's data drop off and only one or two panels producing current.

•

• If there is no or minimal rotation we should only see in the data two panels providing current.

•

• The top and bottom panels may provide more power; it depends on the angle of the sun and the shadow cast by the balloon over the course of the flight.

• The motor attaches to the gear reduction box.

• We will then need to bend copper wire into an “S”. The bottom of the “S” tracks across the circuit board hitting the four panel points. The other end of the wire is at the top of the shaft and must rub against a static piece of wire or copper that is connected to the analogue input.

Schedule of Events• Team Meetings: All Tuesdays at 2:00 p.m.• Design AVR 9/13/09• Design complete 9/20/09• Complete Proposal 9/15/09• Proposal Due 9/17/09 6 p.m. • Conceptual design review 9/ 22/09 8 a.m. • and presentation due • Program AVR 9/27/09• Order all hardware 9/29/09• Prototyping design complete 10/13/09• Testing final design complete 10/20/09• Cold test complete 10/22/09• Mission simulation tests – 10/29/09

bring BalloonSat• Critical design review 10/06/09 8 a.m. • and presentation due • DD Rev A/B due 10/06/09 • Pre-Launch Inspection – 10/27/09

Bring all hardware • Launch Readiness Review 11/03/09 8 a.m. • and Presentation Due • DD Rev C due 11/03/09 8 a.m. • BalloonSat Weigh-in and Turn in 11/06/09 2 p.m.• Launch Day!!! 11/07/09 4:45 a.m.• Final team presentation 12/01/09 8 a.m.

and report due• Data due 12/01/09 In Class• ITLL Design Expo 12/05/09 9 - 4• DD Rev D due 12/05/09 at judging• Team Video Due 12/05/09 at judging• BalloonSat Hardware Turn in 12/08/09

Management

BudgetNeeded Where to Get It Cost WeightHOBO H08-004-02 Gateway program Provided 30

Active heating system “…” “…” 100

External temperature cable

“…” “…”

Canon A570IS digital camera

“…” “…” 220

AVR Microcontroller board + batteries

“…” “…” 150

Foam core “…” “…” To Be Determined

Insulation “…” “…” “…”

Flight string tube “…” “…” “…”

Small motor Hobby Lobby Rotating data combiner ~ $25

RDC ~ 60 grams

Gear reduction kit “…” “…” “…”

Small circuit board “…” “….” “…”

Pieces for rotating arm “…” “...” “…”

Extra wireSolar Panels X 12

http://store.sundancesolar.com/minsolpan5v2.html

$4.50 each($54 total)

~7 grams each

Total $79 602 grams

Budget

Team Member Titles Responsibilities

Hunter Hoopes Software management Block diagramMission objectives

Jess Davidoff Secretary Proposal write up, reporting and presentation preparation

Travis Dowdy Program management AVR diagram and programmingData recovery

Taylor Smith Design management Satellite designDesign documents

Jocelyn Mulkey Organization Schedule managementOrganizational charts

Kaitlyn Zimmitti Budget control/ management

BudgetHardware ordering

Team Member Titles and Responsibilities

Biggest Worries

• Possibilities:– That the motor and gear

reduction box will not work– The solar panels will

break– There will not be enough

sunlight to take sufficient data

– The data doesn’t record properly

– Cloudy weather on launch day