P 14043 Smart Cane Senior Design Final Presentation

P 14043 -Smart Cane Senior Design Final Presentation

Introductions • • • Lauren Bell Jessica Davila Jake Luckman William Mc. Intyre Aaron Vogel – – – Mechanical Engineer Industrial Engineer Mechanical Engineer Electrical Engineer Mechanical Engineer

Agenda • • • Problem Description Design Challenge System Design and Operation Testing and Traceability Project Process Conclusion Recommendations Lessons Learned Acknowledgements

Problem Description Safe and easy navigation in the world is difficult for the blind and deaf/blind Project Goal Inexpensive Intuitive Limited Situation Feedback Expensive Training Required COMMON SOLUTIONS Excellent Situation Feedback

Design Challenge… …To design, fabricate, assemble and validate a ‘haptic handle’ • To be attached to a traditional cane • Provide directional feedback to blind and deaf/blind users

MSD Process Overview Concept Selection • Many ideas to one Design Considerations • Defining the engineering requirements & constraints Generation of Design MSD I • Drawings, Documentation Fabrication and Assembly MSD II Testing of Prototype • Proof that prototype meets eng. requirements

Design Considerations Customer desires needed to be transformed into technical requirements… Customer Desire Technical Requirement Light weight < 1 lbs. Small Grip Diameter < 1. 5 inches Quick Signal to User < 500 milliseconds User Can Detect Direction *Will Elaborate Later Battery Life > 4 hours Learned – Fully understand the customer needs ASAP …otherwise time will be wasted

Potential Concepts Brainstorming and benchmarking yielded the following likely candidates… • • • Track Ball Piston Push Feedback Torque ‘Jerk’ Magnetic Force Feedback Scroll Navigation Learned – Prototyping accelerates the concept selection process

Optimizing Roller Design • Roller Speed • Roller Shape • Bump Height Learned – Quick and simple tests/prototypes will quickly narrow the design. Don’t overanalyze!

Electrical Design Electrical design driven by mechanical design and Engineering requirements

Mechanical Design • ‘Bump’ Roller Sub-assembly • • DC gear motor Roller arms Dowel pins Press fit ball bearings Design provides effective directional feedback

Final Design Documentation of everything is crucial for future project iterations

Fabrication and Assembly • ~25 manufactured parts • Material Changes • Part Modifications • Time management Learned – Fabrication and assembly will expose necessary changes in the design

Testing and Traceability Final tests were within predicted values

Testing and Traceability Prototype meets all non-technical requirements

Problem Tracking System 1. Identifying & Selecting Problem 3. Generating Potential Solutions 2. Analyzing Problem 5. Implementing Solution 4. Selecting and Planning Solution 6. Evaluating Solution Learned – Once problems started to arise and stack up, Problem Tracking significantly helped us manage the problems

Risk Curve Sum of Risks' Importance = Likelihood x Severity 90 Reduction of risks due to analysis (heat, stress, weight) 80 70 60 RISKS: Machining issues with thin ABS covers, ABS back cover breaks during testing phase, PCB not arriving on time 50 PCB working, assembly between handle & cane holds together, wires fit into handle design 40 30 20 10 0 20 -Aug 9 -Sep 29 -Sep 19 -Oct 8 -Nov 28 -Nov 18 -Dec Actual 7 -Jan 27 -Jan 16 -Feb 8 -Mar Planned Useful tool to track actual status against planned 28 -Mar 17 -Apr 7 -May

Project Plan and Efficiency Final Deliverables Task Order Electrical Parts Fabrication of Parts Order PCB Testing Assembly of Handle Technical Paper Total MSDII Tasks Planned Actual Duration Difference Efficiency 14 21 7 67% 18 5 5 34 30 18 16 25 13 53% 17% 28% 5 14 15 27 10 13 33% 52% 83 108 25 77%

Imagine RIT • 200+ “Users” • ~100% Positive Feedback • University News Interview Users at Imagine RIT demonstrated our project met its objectives and was a success.

Lessons Learned üProject Management üCustomer Interaction üCreating a good team dynamic ü“What’s the best thing I can be doing right now? ”

Recommendations • Complete cane with integration to sensors • Improve handle to provide feedback on changes in elevation and proximity of obstacles. • Redesign handle with fewer parts and simple assembly • Attempt to redesign with smaller batteries • Strengthen the outer structure of handle • Water/weather proof

Recommendations for MSD →Shorter presentations in MSD I →Teach project management skills in other courses →Evenly distribute the team resources →Use guides from industry

Acknowledgements • Guides • Gary Werth • Gerry Garavuso • Customers • Dr. Patricia Iglesias • Gary Behm • Tom Oh • Professor Mark Indovina • Jeff Lonneville

Motor Analysis • Torque/speed • Power consumption

Design Grip Pressure Spec • Ensure handle functions under excessive grip • Measure pressure of displaced air for rough idea • Median pressure ~3 psi • Compare to Grip Pressure Study* • • FSR sensors on glove “Crush grip” measured on 50 mm diameter handle 5 male and 5 female adults Maximum pressure ~3. 1 psi • Our measurements matched the study, therefore: • Marginal Grip Pressure: 3 psi • Maximum (Design) Pressure: 5 psi * Tao Guo qiang; Li Jun yuan; Jiang Xian feng, "Research on virtual testing of hand pressure distribution for handle grasp, " Mechatronic Science, Electric Engineering and Computer (MEC), 2011 International Conference on, pp. 1610, 1613, 19 -22 Aug. 201

Required Motor Torque • Maximum moment could happen when: • • Grip reaches design pressure Pressure force is perpendicular to contact point Palm contact area is maximum on roller Two rollers are contacted • Maximum moment caused by design pressure • 50. 1 oz-in • Motor selection will not be heavily constrained • Variety of motors that meet torque, size and rotation requirements

Bump Rotation/Roller Analysis • Bumps per rotation • Servo to Roller Spacing • Effectiveness of our model – Audience?

Roller Force/Stress Analysis

Force/Stress Cont’d