Alternative Terrain Wheelchair Team # 1: Team ARROW Brent Fischer Mitchell Kane Eric Goyette Brennan McVeigh Chris MacKenzie

Outline Current Wheelchairs Design Requirements Considered Designs Selected Design Frame & Drive Budget & Schedule 2

Current Wheelchairs Indoor Use Favored No Suspension No Gearing Soft Tissue Damage 3 [Clipart] - Wheelchair

Alternative Terrain Wheelchair Braking Capabilities Gearing Suspension Repairable With Bicycle Components Ability To Reverse 4 [SolidEdge] – Full Wheelchair

Considered Designs Off-Axle Crank Drive Advantages Proven concept [VarnaHandcycle.com] Fluid Hand Motion Constant Propulsion Disadvantages Smaller Moment Arm Accessibility Issues Snag And Pinch Hazard 5 [SolidEdge] – Off-Axle Crank Design

Considered Designs Same Axle Wheel Drive Advantages No Learning Curve Familiar Design Disadvantages Too Many Chains Snag Hazard Unnatural Motion 6 [SolidEdge] – Same Axle Wheel Drive

Considered Designs Gears with Lever Drive Advantages Ease of Reverse Many Gear Ratios Large Moment Arm Disadvantage Complicated Design Difficult to Manufacture Difficult to Repair 7 [SolidEdge] – Gears with Lever Drive

Selected Design Chains with Lever Drive Advantages Easy to Repair Ergonomic Controls Low Cost Disadvantages Reverse has No Mechanical Advantage Requires Clutch 8 [SolidEdge] – Chains with Lever Drive

Selected Design Features: Roll Bar Adjustable Legs Rests Bench Press Style Motion Many Standard Bike Components Geared Drive 9 [SolidEdge] – Full Wheelchair

Suspended Rear Wheels 29” Treaded Tires Mountain Bike Suspension Independently Driven Wheels Outer Hand Rims 10 [SolidEdge] – Rear Suspension Picture of Shock-absorber

Frame Details Collapsible, Two Folding Cross Members All Aluminum Construction 1” Square Tubing 11 [SolidEdge] – Frame Picture of Tubing

Calculations - FEA Safety Factor of at Least 5 Impact Load Factor of 3 Bending Side Loading Angled Loading Design Considerations 12 [SolidEdge] – FEA

Removable Seat Two Piece Seat Aluminum Framed Weather Resistant Locks on Frame 13 [SolidEdge] – Removable Seat

Adjustable Foot Rests Removable Adjustable Independent Convenient for Amputees 14 [SolidEdge] – Foot Rests

Safety System Waist Restraint Roll Bar Suspension Reflective Tape 15 [SolidEdge] – Center of Gravity [SolidEdge] – Roll Bar

Drive System Front Castor Wheels Suspended Rear Wheels Chain Lever System Accessible Brakes, Gearing, Clutch 16 [SolidEdge] – Full Wheelchair

Chain Lever System Five Gears Available Parts Clutch to Reverse Chain Tensioner 0.79 to 2.45 Gear Ratio 17 [SolidEdge] – Chain Lever System

Clutch Assembly Located Centrally Non-Standard Clutch Easy to Assemble 18 [SolidEdge] – Clutch Assembly

Calculations – Gear Ratios 19 Max Ratio Min Ratio

Build Report Budget Many off the Shelf Items Standard Metal Sizes Sponsorship Search Ongoing SubTotal$1,877 Tax$263 Contingency (5%)$94 Total$2,234 Outside Donations$1,000 ME Departmental Donation $1,000 Total$2,000 Net-$234 20

Schedule Construction to Start After Exam Period Aluminum Welding in Question Testing by February 1 Completion by March 1 21

Conclusions Design Requirements Met Design Essentially Completed Structural Materials Purchased Building and Testing March First 22

Special Thanks Mechanical Engineering Faculty Dr. Georgiades Pam MacDougall ME Class of

Questions 24