Web Posted on: March 3,1998
USING COMPUTER-CONTROLLED LABORATORY EQUIPMENT TO DESIGN ACCESSIBLE EXPERIMENTS
Karen Milchus
Center for Rehabilitation Technology
Georgia Tech., Atlanta, GA 30332-0156
Voice: (404) 894-4960
FAX: (404) 894-9320
Internet: karen.milchus@arch.gatech.edu
Science laboratory activities pose many barriers to students with disabilities. This session will demonstrate several ways that high school or college level chemistry and physics laboratory activities can be made accessible to students with physical or visual disabilities. Computer-controlled lab equipment can be combined with assistive technology to provide a means for students to make scientific measurements. This equipment, along with other assistive technology and alternative techniques, was used to design a set of accessible chemistry and physics experiments for high school and college level classes.
BACKGROUND
Students with disabilities face a variety of barriers in accessing science lab activities. While schools have begun to eliminate architectural barriers, laboratory activities have not been addressed, and equipment is usually inaccessible. Students with visual impairments have difficulty reading measurement devices such as graduated cylinders, and multimeters. Likewise, students with mobility impairments have obvious difficulties manipulating equipment such as pipettes and gages. By not being able to participate in science labs, these students are discouraged from taking science courses and pursuing technical careers.
Under a current NSF project, "Developing Accessible Laboratory Experiments", the presenter is developing a series of accessible laboratory experiments for high school and college level chemistry and physics courses. One approach is to use computer-controlled lab systems that are combined with common alternative access methods. Students with disabilities can then conduct experiments themselves. For example, a computer can record measurements from a pH electrode, and the readings can be magnified or spoken by a synthesizer for students with visual impairments.
It may not be possible to make an experiment fully accessible for a particular student, but our goals are to let the students conduct as much of the experiment themselves as possible, and to enable them to make the required scientific decisions during the course of the experiment.
APPROACH
Computer-controlled laboratory equipment is becoming incorporated into more high school and college chemistry and physics courses. A sensor, such as a temperature probe, is connected to the computer, and specialized software controls the timing of measurements and the recording and display of data. Even without any other accommodations, the larger display and pull-down menu controls of these systems can make data acquisition easier for some students with disabilities. Dr. David Lunney of East Carolina University has achieved even greater accessibility for students with disabilities by adapting laboratory computers with assistive technology. [3] However, his work has focussed on specialized computer systems. Our approach is to combine the relatively inexpensive computer interfaces and software Technologies more commonly found in introductory labs with common alternative computer access methods so that students with disabilities can conduct experiments themselves. For example, a computer can record measurements from a light sensor, and the readings can be magnified or spoken by a synthesizer for students with visual impairments. A student who has difficulty using his or her hands can control the timing and recording of measurements through voice commands.
We are developing detailed instructions for science teachers on how to add assistive software to computer-controlled lab software to make it fully accessible. Two lab control systems, Vernier Software's Universal Lab Interface and SCI Technology's LabWorks II are presently being tested on IBM and Macintosh computers with access software. A variety of sensors are available for each system, and basic set of interface hardware, software, and a couple of sensors cost $300-1200. The access software includes keyboard access utilities (e.g., StickyKeys), on-screen keyboards with mouse emulators, voice input programs, magnification programs, and voice output programs. We have discovered, for example, that the more standard DOS software for the Vernier lab interface will not run simultaneously with other software (such as MouseKeys). Students who need software-based assistive technology would need to use the new Windows 95 interface software (which has shown to be compatible). As the combinations of technology are being tested, project personnel are developing configuration files and customizing the software as needed to permit access to the information displayed by the computer. We will complete the testing and customization in the next few months, and a panel of students with disabilities will test the software combination for usability.
Many laboratory tasks cannot be replaced easily with computerized sensors and require additional assistive technology or techniques.[1,2,5] Existing assistive technology is being identified and other approaches are being developed. For example, solvents can be measured out via the standard graduated cylinder or pipette, but might also be measured with liquid measuring spoons, a syringe, or by weight.
RESULTS
The information on using computer-controlled lab software, computer access technology, and other assistive technology is being combined to create a series of twelve sample accessible chemistry and physics experiments. Some of the chemistry experiments include Conductivity of Electrolytes and Non-Electrolytes (using a conductivity meter or voltage probe), Gas Laws (using pressure and temperature probes), and Chemical Equilibrium (using a colorimeter). The physics experiments include Force and Motion (using accelerometers, force sensors, and photogates), Electrical Measurements (using voltage measurement leads), and Properties of Light (using a light sensor). These experiments use a variety of measurements and related laboratory techniques.
Although this project focussed on chemistry and physics, teachers of other science disciplines should note that barometers, carbon dioxide gas sensors, dissolved oxygen probes, heart rate monitors, and Geiger counters can also be interfaced to these computer systems. Thus, similar access could be provided in Biology or Earth Science classes.
The experiments and accommodations developed for this project are being compiled into a resource guide.[4] The guide is also available to the public via the Internet site Barrier Free Education: Resources for the Inclusion of Students with Disabilities into Math and Science Education -- http://barrier-free.arch.gatech.edu/BFE/
REFERENCES
- Cetera, M.M.(1983). Laboratory Adaptations for Visually Impaired Students: Thirty Years in Review." Journal of College Science Teaching, 12, 394-93.
- Blumenkopf, T.A. et al.,(1981). Mobility-Handicapped Individuals in the College Chemistry Curriculum: Students, Teachers and Researchers." Journal of Chemical Education, 58, 213-221.
- Lunney, D. and Morrison, R. C.(1994). Development of a Data Acquisition and Data Analysis System for Visually Impaired Chemistry Students. Journal of Chemical Education, 71(4), 308. 4. Milchus, Karen and Goldthwaite, John (1998). Developing Accessible Laboratory Experiments. Center for Rehabilitation Technology, Atlanta, GA. Draft.
5. Willoughby, Doris(1989). Handbook for Itinerant and Resource Teachers of Blind and Visually-Impaired Students. National Federation of the Blind, Baltimore, MD.
ACKNOWLEDGEMENTS
This project was supported by the National Science Foundation, grant #: HRD-9700150. Additional support for the website has come from the Toyota and NEC Foundations.