Back Assist.ppt

1、Back Assist,A Proximity Sensor for Wheelchairs,Team 24,Stephanie Toth Isabelle Harroch Alexander Silverman Kevin Lynch Daniel Lofaro (Captain),Outline,Problem Statement Problem Background Work Done Towards Solution Final Solution Technical Background of Solution Other Technical Information Summary,P

2、roblem Statement,1.5 Million Americans in wheelchairsHazards Tables Chairs Other People Stairs,Problem Background,AccessoriesPower Rolls IVCurb - ClimbingMAid,Accessories,Joysticks Light Batteries Electromagnetic Brakes Anti-Tip Solid Wheels Swinging Support With Hand Grips Sensing Devices,Power Rol

3、ls IV and Curb-Climbing,Source:,Source:www.wws.princeton.edu,MAid,Source:ieeexplore.ieee.org,Design Decisions,Methods of Object DetectionActive vs. Passive ResponseHuman/Computer InterfaceFinal Solution,Methods of Object Detection,Ultrasonic Sensor,Infrared Sensor,Source: Original,Source: Original,A

4、ctive Response,Advantages Easier on wheelchair operator More accurate than humans Disadvantages Could lead to worse locations Prone to false reactions Users over reliance,Passive Response,Advantages Eliminates active response problems Allows the user to remain in controlDisadvantages Not as responsi

5、ve,Human/Computer Interface,Source: Original,Final Solution,Ultrasonic sensors Parallel sensors Objects in rear Arm rest support Downward sensors Sudden drops Lower chair body,Sensor Orientation,Created with the help of Jon Bowen,Sensor and Control Box Placement,Source: ,Parallel Sensor Placement,Do

6、wnward Sensor Placement,Control Box Placement,Final Solution Continued,Control Box Armrest LEDs Parallel Indicators 2 Yellow LEDs 2 Red LEDs Downward Indicators 1 Red LED Waterproof,Control Box,Source: Original,Back Assist Prototype,Source: Original,Prototype Schematics,Source: Original,Proximity Wa

7、rning,Green 45-60 cmYellow 25-45 cmRed 0-25cm,Proximity Warning Program,Source: Original,Stairs Warning,Green No Stairs “Safe”Red Stairs “Warning”,Stairs Warning Program,Source: Original,Constraints and Environmental Impacts,Constraints See Objects Cost FCC RegulationsEnvironmental Disposal,Budget,1

8、000 Units Produced Production Cost: $153,000 50% Overhead Total Cost: $230,000 Unit Selling Price: $250 Profit: $20,000 - $90,000 Prototype Cost: $115 + Development CostsAll amounts are estimates,Summary,Aware of Objects Easy Visual Output Cost Effective,Thank You,For more information please visit http:/BackAssist.webhop.org,