Enhanced Navigational Aid For the Visually Impaired Peter Okma (CPE) Abhay Sampath (EE) Katelyn Sapio (EE) 04/28/2010

Presentation Outline 1.Project Formulation Peter Okma 2.Design Specifics Abhay Sampath 3.Additional Considerations Katelyn Sapio

Problem There is a need for devices to aid the visual impaired with navigation Widely used solutions don’t take advantage of modern technologies – Seeing eye dogs, canes, etc. The few high-tech solutions currently available are not very effective and are extremely expensive – MOWAT, Laser Cane

Project Goals Design a device that will provides useful feedback to enhance the navigational ability of the visually impaired The device should be – Useful – Portable – Reliable – Affordable

TechnologyCostAccuracyMobilityComplexity Power Consumption LIDARVery HighExtremely Accurate Very LowVery Complex Very High Camera Recognition HighMediumLowComplexVery High EcholocationLow HighModerateLow Directional Ultrasonic Medium AccurateHighModerateLow Solutions Considered

Chosen Design

High-Level Algorithm Sensor reads distance Microcontroller gets the direct distance reading, then computes the differential reading

Intuitive Implementation Amplitude proportional to distance Pitch proportional to velocity (differential distance) Difference between either ear is related to angle Sensor information is delivered through the corresponding speakers

Functional Flowchart

System Model

Economics Ultrasonic Sensors$120 – Maxbotix LV-MaxSonar-EZ Speakers$15 Microcontroller & Board$65 – Arduino Mega2560 – Atmel ATmega2560 Miscellaneous$50_____ Total$250

Health and Safety Should not obstruct hearing – Software: Beeps vs. constant tone – Hardware: Shape of headgear Safety Risks – Product meant for eye level detection Learning Curve – Battery Life – Calibration and Accuracy

Ethical Responsibilities Reliability vs. Cost – Software: Must act with minimal delay – Hardware: Accuracy and reliability must be maximized Marketing: Risks and limitations should be made clear – Ex: This device cannot sense elevations in floors, so it must be used with a cane or a seeing eye dog

Conclusion Improvements on existing products – Omni-directional awareness – Velocity Recognition – Comfort/Aesthetics – Intuitive audio feedback – Low Cost

References Fast and robust tracking of multiple moving objects with a laser range finder A comparison of line extraction algorithms using 2D laser rangefinder Laser range finder based on synchronized scanners Compact laser radar and three-dimensional camera