RC Airplane

Robert SchuldAakash SoniAlan Strimbu

Table of Contents Timeline Gantt Chart Problem Statement Background Customer Scope Customer Requirements Deliverables Brainstorming Research Identify Criteria & Constraints Explore Possibilities Pros and Cons Select an Approach CAD Bill of Material Build Process Test Criteria Test Plan Prototype Test Results Lessons Learned Summary

Timeline

Gantt

Problem Statement

Students lack proficiency in Engineering

By creating an RC airplane: Gain knowledge Gain experience for college environment

Background

Gain knowledge in Aeronautics and Material Sciences

Implement calculus and physics for advanced calculations

Recognize properties of different materials – balsa wood, foam, etc.

Customer

Mr. Pritchard

Mrs. Brandner

Scope

Create RC airplane to takeoff, fly, and land

Consist of fuselage, wings, motor, servos

Documented in engineering notebook Presented in technical report and

Powerpoint presentation

Scope (cont’d)

Experts Mr. Pritchard Mrs. Brandner Mr. Cotie

Built of balsa wood and foam Held together with various glues Create lightest prototype as possible

Scope (cont’d)

Requirements 12-step design process Strength tests Cost estimates CAD drawings Data for 3 diff. materials Calculations for plane (thrust, drag, lift)

Scope (cont’d)

Expected cost to be $100

Limitations with various clubs and sports

Customer Requirements Mr. Pritchard

3 tests on 3 different materials Strength test on material/prototype

Mrs. Brandner Complex calculations using physics and calculus Submit engineering notebook

Additional Must fit in technology room Must be tested outside school property

Deliverables

Mr. Pritchard RC Airplane prototype Final Report Design Notebook(s) Powerpoint Presentation

Mrs. Brandner Calculations

Brainstorming

Construction What building materials will be used? What bonding materials will be used? What prefabricated materials will be

used? What tools will be used?

Brainstorming (cont’d)

Plane characteristics How will the airplane be powered? How will the airplane be maneuvered? What weather conditions are required to

fly the plane? What wing structure will be used? What aesthetics will we consider? What is the optimal center of gravity?

Brainstorming (cont’d)

Testing Where will we fly the airplane? What if the airplane crashes? Will we need permission to fly the

airplane? How will we test the airplane?

Research

Looked heavily into materials Balsa vs. Basswood Foam vs. Metal vs. Fiberglass

Structure of plane Skeleton build with thin covering Solid build

Research (cont’d)

Motor types Electric, nitro engine, jet engine

Servos Move surfaces of plane Provide turning capabilities

Propeller/Landing gear Propeller needs to fit with motor Proper size wheels

Research (cont’d)

Plane channels Ailerons for roll Elevators for pitch Throttle for speed Rudder for yaw Electronic Speed Controller (ESC) 3-channel system most practical

Research (cont’d)

Wing position High, mid, and low-wing High is most stable and easiest to fly

Tail V-tail and T-tail T-tails better with low speeds for control

Transmitter Prefabricated at 72 MHz frequency band

Identify Criteria & Constraints

Criteria Applications of Calculus

Calculations for d(t), v(t), a(t) Calculations for lift force Calculations for engine torque Calculations for thrust Calculations for types of materials Optimization with different materials and

structures Submit engineering notebooks

Identify Criteria & Constraints Criteria

Applications of Technology Application of the 12 step design process

Testing procedures for different types of materials and their strengths

Submit final report and Power Point

Submit airplane prototype

Submit CAD drawings

Identify Criteria & Constraints

Criteria Control Panels Flying tests must be outside school

property

Constraints Must fit inside technology room 3 ft. wingspan for detail, but not too

large

Explore Possibilities

Pros and ConsMaterials Pros ConsBalsa wood Porous

Less glue required Lightweight Cheap Widely available Stiff Easy to sand

Varying strength

Basswood Won’t crush Lightweight

Hard to sand Not widely available More expensive

Foam Very lightweight Hard to work with Not very strong

Plastic Strong Rigid

Rigid Hard to work with Expensive Relatively heavy

Metal Very strong Rigid

Very heavy Expensive Hard to work with Not widely available

Fiberglass Very strong Very lightweight

Very expensive No previous experience Not widely available

Pros and Cons (cont’d)

T-tail best choice Aerodynamics Cleaner airflow

Tails Pros ConsV-Tail Lightweight

Less drag Sturdy

Less aerodynamic

T-Tail Keep airflow behind wing Creates clean airflow Better pitch control

Can break at landing

Pros and Cons (cont’d)

High wing best choice Easiest to fly/build Stable Makes sustained flight easiest to attain Acrobatics not necessary

Wings Pros ConsHigh wing Most stable

Easiest to fly Easy to build

Not as acrobatic

Low wing Easy to roll Hard to fly Top-heavy

Mid-wing Easy to turn Hardest to fly Wings at bulk of mass

Pros and Cons (cont’d)Adhesives Pros ConsWood Glue (Urea) Easiest to use

Low cost Light color

Poor heat resistance Poor moisture resistance Bond not very strong

Hot Glue Quick cooling time Relatively easy to use Low cost

Bond not strong Leaves residue Visible on plane

Gorilla Glue Very light Expands while setting Best for wood than other

materials Waterproof

Hard to work with Contains air bubbles Somewhat expensive

Pro-bond Glue Expands when dry Less glue required Cheap Water-resistant

Heavy

Rubber Cement Strong flexible bond Easy to peel off Not brittle

Flammable Highly toxic Expensive

Super Glue Very strong bond Often used for model aircraft Versatile Water resistant

Expensive Can become brittle Long cure times

Pros and Cons (cont’d)

Propellers Pros Cons

Dual Blade Easily available Very efficient Easy to use Fairly cheap

Larger diameter

Multi Blade Smaller diameter Less available Less efficient

Wood Blade Very rigid Efficient Light

Breaks easily

APC Blade (Metal) Don’t break as easily Efficient

Heavy

Pros and Cons (cont’d)Motors Pros ConsElectric Cheap

Easy to run Clean Doesn’t require gasoline Lightweight

Low power / torque

Nitro Relatively cheap Wide availability High torque and power

Special mixture of fuel Heavy

Gas High torque and power Not as available Heavy Special mixture of fuel Expensive

Jet Extreme power Extremely expensive Not as available

Select an Approach

Design 1

Design 2

Design 3

Effort

IMPACT

High

Low

Low High

CAD

Bill of MaterialPART PART DESCRIPTION COST PER UNIT QUANTITY TOTAL COST

Power 15 Brushless Outrunner Motor

950 Kv, 575 Watts $79.99 1 $79.99

3-channel controller Hitec Neon SS 72 MHz

$67.99 1 $67.99

Landing Gear Elite Mini UltraStick $12.95 1 $12.95

Servos HS-311 6.0 Volt $11.99 2 $23.98

Carbon fiber tube 0.210” outer diam. x 0.132” inner diam. x 40”

$7.99 1 $7.99

EPS Foam ¾” x 14 ½” x 48” $9.49 1 $9.49

Propeller Speed 400, 5.25 x 6.25 $2.13 1 $2.13

Pushrods Fiberglass $8.95 2 $17.90

Balsa Wood ¼” x 36” $0.89 2 $1.78

TOTAL COST $224.20

Build Process

Part A Layer four sheets of EPS foam on top of each

other. Use four very thin dowel rods or four vise grips

and stick it through all four layers in each of the four corners of the stack in order to hold it in place.

Using a Sharpie, mark a rectangle that is 4” x 23” on the top of the stack.

Using a hot wire, carve out the resulting box.

Remove the cut out pieces. Clamp these four pieces together so that all of the

edges are flush. Using a box cutter, shave out the shape of the

fuselage. Remove the vise grips and glue the four sheets

together. Sand Part A so that it is smooth.

Build Process (cont’d)

Build Process (cont’d)

Part B Obtain one sheet of EPS foam. Using a Sharpie, trace the side of Part B on the

end of the foam sheet. Using a hot wire, trace this line and cut out the

shape of Part B.

Build Process (cont’d)

Build Process (cont’d)v

Build Process (cont’d)

Build Process (cont’d)

Build Process (cont’d)

Test Criteria

Test Criteria for Prototype Safety Functionality (in air/on ground) Ease of use Aerodynamics Velocity Weight/Size Strength

Test Criteria

Test Criteria for Materials Foam

Strength Safety Compression/Tension Flexibility Weatherability (ability to withstand outdoor

conditions)

Test Criteria Test Criteria for Materials

Adhesive Weatherability Holding strength Drying time

Motor/Propeller Thrust Torque Voltage (if necessary) Weatherability Weight/Size Functionality

Test PlanTest Criteria How Tested Expected results Actual Results

Overall Plane Aerodynamics Look at the overall body of the plane and determine if any parts of the plane will decrease aerodynamics.

The plane will have sound aerodynamics and will have minimal drag.

Functionality Move all surfaces (rudder, elevators) and check for responsiveness.

All motorized parts of the plan will respond well.

Safety Check if the plane flies consistently in the air and doesn’t wobble.

The plane will be safe and won’t wobble.

Strength Hang weights on the wings and see if the flex too much or break. Put weights on other critical structures of the plane.

The plane will be able to support the weight and will not fracture.

Velocity While in the air, look at distance/time to determine the speed.

The velocity will be high enough to sustain flight.

Weight/Size Measure the overall plane’s dimensions. Put the whole plane on a scale.

Plane’s weight will be in proportion to its size.

Prototype

Test Results

Lessons Learned

Summary