1 me 442 senior project week 3 dr. joseph vignola pangborn g43, phone 202-319-6132,...

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ME 442 Senior Project Week 3

Dr. Joseph VignolaPangborn G43, Phone 202-319-6132, [email protected]

Tuesdays & Thursdays, 9:35-12:25 AM, Pangborn G43

Office Hours: Tuesdays, 1:00-2:00 PM

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University MassThe University Mass is today so will finish today at 11:50

The mass begins at 12:10 pm in the upper church of the Shrine,

Taken from http://patheoldminer.rootsweb.ancestry.com/faybuffington.html

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DocumentationPlease bring all your electronic files everyday

SolidWorks drawings


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SolidWorks drawingsExcel budget


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It’s best to use the document that I started

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It’s best to use the document that I startedIt’s on the class web page

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PurchasesI need to see the Excel budgets today and Thursday

I want to be sure we are keeping careful track of all expenses.


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Materials and PurchasingIt is very import that you start purchasing now

There will be problems with the credit card

Ask Ken to bring specific material you need


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Machine ShopPlease work with Don, Hong or anyone that has built things

Show them sketches of ideas and be open to changes


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Show them sketches of ideas and be open to changes Simplify your design


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Show them sketches of ideas and be open to changes Simplify your design

Settle on the details


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Machine Shop SafetyWe now have the School of Engineering Safety Rules

Everyone must read, understand and sign

Signature page must be clear and readable

Schedule shop time with Hong


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Assignment 2Fix assignment 1

The first six (now five) part design support document was due Tuesday. Want an A? Generally speaking come talk to me before its due and I will go over it with you.

I’ll help you edit it and then you’ll have all the information the A will be yours.

We will start with group 1 and work backwards

Maybe I can do two groups at a time


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Toolbox Please just list what you need to carry to the airfield.

Glue that take overnight to dry is probably not appropriate for that list but cyanoacrylate glue (Superglue) is

You should know what each screw is for


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You should know what each screw is forPlease don’t list random items


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You should know what each screw is forPlease don’t list random items ¼” screws


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You should know what each screw is forPlease don’t list random items ¼” screws, a hammer


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You should know what each screw is forPlease don’t list random items ¼” screws, a hammer, weed wacker


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Ask Jason, Hong, Ken or me what you really need


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Myths and TruthsMyths Gorilla Glue is no stronger than ordinary carpenters glue


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Myths and TruthsMyths Gorilla Glue is no stronger than ordinary carpenters glue You can make a part bigger then the travel range of the CNC machine


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Ken brought enough wood for everyone


Ken

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Ken brought enough wood for everyone

Purchase always come through as hoped


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Myths and TruthsTruthsRound holes are easier to make then not round holes


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Myths and TruthsTruthsRound holes are easier to make then not round holes

Hong needs some sleep


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You need to know where the CG isWeighted averages.

x

y

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Mass and Aerodynamic Centers Weighted averages.

x

y

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Mass and Aerodynamic Centers Weighted averages. Pick an origin

x

y

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Mass and Aerodynamic Centers Weighted averages. Pick an origin, make a table

x

y

component Mass (kg) x-location (cm)

engine 0.45 -3

fuselage 2.1 75

Wing 2.3 27

Front landing gear 0.35 12

Rear landing gear 0.64 34

Fuel tank 0.33 8

Radio reciever 0.25 7

tail 0.75 150

Payload

Total 7.17 319

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Mass and Aerodynamic Centers Weighted averages. Pick an origin, make a table

x

y

component Mass (kg) x-location (cm)

engine 0.45 -3

fuselage 2.1 75

Wing 2.3 27

Front landing gear 0.35 12

Rear landing gear 0.64 34

Fuel tank 0.33 8

Radio reciever 0.25 7

tail 0.75 150

Payload

Total 7.17 319

51.2 cm

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Mass and Aerodynamic Centers Each component that is exposed to the exterior flowHas a net drag force that acts on that component

The magnitude of that force is

51.2 cm

These drag forces occur at specific locations

These location must be determined

Once you have them

x

z

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Mass and Aerodynamic Centers Each component that is exposed to the exterior flowHas a net drag force that acts on that component

The magnitude of that force is x

z

51.2 cm

These drag forces occur at specific locations

These location must be determined

Once you have them

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Mass and Aerodynamic Centers

x

z

51.2 cm

Once you have them…

DRAW A FREE BODY DIAGRAM

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Mass and Aerodynamic Centers Once you have them Then sum forces andmoments

mg

thrust

Wing drag

tail drag

fuselage drag

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mg

thrust

Wing drag

tail drag

fuselage dragx

z

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mg

thrust

Wing drag

tail drag

fuselage dragx

z

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mg

thrust

Wing drag

tail drag

fuselage dragx

z

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mg

thrust

Wing drag

tail drag

fuselage dragx

z

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Mass and Aerodynamic Centers This summing for moments is precisely the same as the weighted average

x

z

51.2 cm

component Net drag (N) z-location (cm)

x-location (cm

fuselage 2.7 5 44

Wing 15.3 17 45

Front landing gear

3.5 -12 34

Rear landing gear

5.8 -11 76

tail 13.7 21 125

Total 40.7

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You MUST include this informationThis summing for moments is precisely the same as the weighted average

x

z

51.2 cm

component Net drag (N) z-location (cm)

x-location (cm

fuselage 2.7 5 44

Wing 15.3 17 45

Front landing gear

3.5 -12 34

Rear landing gear

5.8 -11 76

tail 13.7 21 125

Total 40.7

So have a figure with YOUR plane, a coordinate system, and the location of the centers

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Design to Meet ObjectivesThe objectives are requirements and constraints

Requirements and constraints are separate

Requirements: what you are expecting from the full system or subsystem

Constraints: what you are stuck with

They must be specific

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Landing gear must be strong enough

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Landing gear must be strong enough

Must remain elastic for 3 f/s vertical fall will transferring less that a 2 g impulse to the fuselage

Requirements and ConstraintsThere MUST be requirements and constraints for the plane itself Every subsystem MUST have bulletined requirements and constraints listed separately

The should have numbers and be specific

Fuselage RequirementsHold: 4 cell battery (based on 6 minute flight)z57 model radio receiver (with link to data sheet)27 lbs payload at plane’s unloaded CG and wing’s CLRemovable wing mount able to transfer 42 lbs from wing to fuselage. Engine mount within ± ½ in of current estimate of plane’s aerodynamic centerTransfer 2 x planes full weight (84 lbs) to landing gear…

Support 2.5 lb horizontal force generated by tail with rudder at full deployment…

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ME 442 Senior Project Week 3

Dr. Joseph VignolaPangborn G43, Phone 202-319-6132, [email protected]

Tuesdays & Thursdays, 9:35-12:25 AM, Pangborn G43

Office Hours: Tuesdays, 1:00-2:00 PM

Week 3

Build

Week 3

Please email your t-shirt size to Ms. Hicks and Nicole Bull

[email protected]

Today I would like to see Excel budgets

1 me 442 senior project week 3 dr. joseph vignola pangborn g43, phone 202-319-6132,...

Documents

machi shopplease work

fix assignment

work backwardsmaybe

machi shop safetywe

design support document

class web page

sign signature page

readable schedule shop