Motor Assisted Wheelchair Design Review 100115 Team Members
Motor Assisted Wheelchair Design Review 10/01/15
Team Members
Agenda • Our day in the life of the wheelchair- Everyone • Where we want your help • Improvements from last phase • Functional Decomposition • Morphological Chart • Concept Development • Pugh Selection • Functional Architecture • Benchmarking • Risk Analysis • Plan Moving Forward
Day in the Wheelchair • Brenden- "severely underestimated how long it would take to go somewhere" • Nick- “ going long distances outside was not ideal” • Alan- " 'flat prison' is a real concept" • Brad- "this campus is bigger than I thought" • Dat- "going down a slope is dangerous, going up is very difficult" • Jason- "turning is so difficult"
Your Help • Have we missed any functions even through review with the end user? • Any further ideas of user input for control? • Does the design chosen seem feasible? • Any design based risks that we haven't covered yet?
New Use Scenario
Customer Requirements Rephrased: Functional in various weather (rain, snow, etc) and road (paved, gravel) conditions Rephrased: Adjustable speed to walk with friends Rephrased: Safe to use during normal operation and when something unexpected occurs
Engineering Requirement Changes Combined into Stored Volume
Current Engineering Requirements
House of Quality Changes Before Revised
Functional Decomposition
Morphological Table Options
Concept 5: Combination of Concepts 1 and 3, generated after Pugh Analysis • Retractable Cord to outlet - Access Energy • Battery - Store Energy • Electric Motor - Convert Energy • Light Feedback - Feedback • Omniwheel Addition - Apply Force • Force Sensor + Dimmer Switch - Operational and User Input
• • • Concept Selection Criteria Weight of addition Cost Able to be designed and built within 2 semesters Easy to transport & store Usable for a long period of time without needing to stop to replenish energy source Level of speed control available Independence level granted to the end user Impact on the overall dimensions of the wheelchair when the addition is added Allows the user to walk with friends Assists user going up an incline
Concept Selection Concept 1 Concept 3 Concept 2 Concept 4 Concept 5
Concept Selection Concept 1 Concept 3 Concept 2 Concept 4 Concept 5
Selected Concept 5:
Feasibility via Benchmarking Overall Benchmarking Motor Benchmarking Battery Benchmarking Switch Benchmarking
CAD Drawings of Current State CAD Mockup of a wheelchair setup. Will serve as the basis for creating drawings of the assist device placement. Taken from Grab CAD.
Preliminary Test Plan User Interface Criteria
Risks of Chosen Design • Misusing Parts Unintentionally - Societal/Personal • Removable Piece: Falls off on its own - Technical • Removable Piece: Impact Failure - Technical • Battery: Catches Fire, Physical Leaks - Safety/Environmental • Motor: Catches fire or burns out - Safety • Retractable Cord: Wears out from repeated use - Technical • Omniwheel: Slipping along ground - Technical • Sensors: False Input/Output - Safety • Sensors: Dimmer Switch doesn't work - Safety
Looking Ahead
Vision for Next Phase • Decide on specific solutions for each subsystem and how those subsystems will interface. • • Mechanical - motor selection, wheel selection/placement/mounting mechanism on the existing wheelchair Electrical - battery selection, user interface Perform feasibility analysis of each solution selected to ensure that it will be able to achieve engineering requirements. Create high level drawings of each subsystem to show the components in each subsystem interface with one another. Begin generating a preliminary bill of materials. Continue updating risks. Further develop test plans.
Questions?
- Slides: 33