Questions and Answers

EE502 - HW #2 – STUDY QUESTIONS

(Questions marked with * are OPTIONAL but useful as a study guide)

The following questions come from Chapter 8 of the textbook by Cook

& Polgar:

8.3 Compare the visual, auditory, and tactile systems in terms of their basic function and as substitutes

for each other.

8.9 What special problems does the GUI present for persons who are blind?

8.10 (Optional for bonus credit) What are the features included in the Universal Access and Windows

Accessibility options that assist individuals who have low vision or blindness?

8.11 List three limitations of current voice-only screen reading programs developed for visual access.

8.13 Describe the relative advantages and disadvantages of software and hardware approaches to

obtaining enlarged displays for persons with visual impairments?

8.17 (Optional for bonus credit) What is the primary tactile method used for (displaying) computer

output?

8.29 What are the major barriers to computer use reported by individuals who are blind or have low

vision?

8.30 What are the primary challenges in obtaining Web access for people with disabilities?

8.37 What are the major limitations of the long cane for use as a mobility aid by persons who are

blind?

8.39 List three advantages and three disadvantages of the laser cane.

8.41 What are the major assistive technologies applied to orientation for people who are blind?

The following questions come from in the Course Reader - Szeto's

Chapter 5 on “Rehabilitation Engineering & Assistive Technology”

5-3 (Optional for bonus credit) Write a sample set of performance specifications for a voice-output

oscilloscope to be used by a visually impaired electrical engineering student for a laboratory

exercise having to do with operational amplifiers. What features would be needed in the

proposed oscilloscope?

5-21 An electronic guide dog has been proposed as an electronic travel aid for a blind person. List

some of the specific tasks that such a device must be able to do and the information processing

steps needed to realize such an assistive device. List as many items and give as much details as

possible. Hints: Consider the problems of obstacle detection, information display, propulsion

system, inertial guidance, route recall, power supply, etc.

5-24 Safe and independent mobility by persons with severe visual impairments remains a challenge.

To alleviate such persons of their dependence on guide dogs or a sighted human guide, various

portable navigational aids using a Global Positioning System (GPS) receiver have been

marketed.

(a) Conduct an internet investigation of GPS as the basis for a portable navigational aid for the

blind. Answer the following questions: How does GPS work? Can GPS signals be reliably

received and detected at every location? How accurate are GPS signals in terms of resolution?

Is this level of resolution sufficient for finding the entrance to a building?

(b) Describe the various operational requirements of an ideal portable navigational aid for the

blind. Consider such ergonomic issues as the user interface, input and output requirements,

and target retail price. List some of the human factor design issues involved.

The following questions come from the Course Reader - Szeto’s

Chapter on "Assistive Technology for the Blind and Visual Impaired"

1. List the advantages and disadvantages of a paperless Braille system versus paper

Braille.

2*. [Optional for Bonus Credit] Describe, contrast, and compare the electrocutaneous

and vibrotactile approaches for tactile sensory aids. [Hint: You may need to search for

additional background on the internet to answer this question.]

3. Describe the technical processing steps executed by the Kurzweil reading machine to

recognize a character. [Hint: You may need to search the internet to answer this

question more completely.]

4. List and briefly describe 3-4 major differences between mobility and reading aids for

the blind in terms of their design goals, operating milieu, and consequences of errors.

5. List the major approaches used in Electronic Travel Aids (ETA’s) to detect (or

interrogate) the environment and feedback environmental information to blind users.

6. What are the major design considerations or goals for ETAs? Describe how these are

met (or not met) in the Laser Cane, the Sonicguide, and Mowat Sensor (or its

equivalent successor). [Hint: You may need to use the internet to find out more about

these assistive devices.]