Richard C. Simpson

How many people would benefit from a smart wheelchair

Independent mobility is important, but some wheelchair users find operating existing manual or powered wheelchairs difficult or impossible. Challenges to safe, independent wheelchair use can result from various overlapping physical, perceptual, or cognitive symptoms of diagnoses such as spinal cord injury, cerebrovascular accident, multiple sclerosis, amyotrophic lateral sclerosis, and cerebral palsy. Persons with different symptom combinations can benefit from different types of assistance from a smart wheelchair and different wheelchair form factors. The sizes of these user populations have been estimated based on published estimates of the number of individuals with each of several diseases who (1) also need a wheeled mobility device and (2) have specific symptoms that could interfere with mobility device use.

Participatory design in the development of the wheelchair convoy system

BackgroundIn long-term care environments, residents who have severe mobility deficits are typically transported by having another person push the individual in a manual wheelchair. This practice is inefficient and encourages staff to hurry to complete the process, thereby setting the stage for unsafe practices. Furthermore, the time involved in assembling multiple individuals with disabilities often deters their participation in group activities.MethodsThe Wheelchair Convoy System (WCS) is being developed to allow a single caregiver to move multiple individuals without removing them from their wheelchairs. The WCS will consist of a processor, and a flexible cord linking each wheelchair to the wheelchair in front of it. A Participatory Design approach – in which several iterations of design, fabrication and evaluation are used to elicit feedback from users – was used.ResultsAn iterative cycle of development and evaluation was followed through five prototypes of the device. The third and fourth prototypes were evaluated in unmanned field trials at J. Iverson Riddle Development Center. The prototypes were used to form a convoy of three wheelchairs that successfully completed a series of navigation tasks.ConclusionA Participatory Design approach to the project allowed the design of the WCS to quickly evolve towards a viable solution. The design that emerged by the end of the fifth development cycle bore little resemblance to the initial design, but successfully met the projects design criteria. Additional development and testing is planned to further refine the system.

A perspective on intelligent devices and environments in medical rehabilitation

Globally, the number of people older than 65 years is anticipated to double between 1997 and 2025, while at the same time the number of people with disabilities is growing at a similar rate, which makes technical advances and social policies critical to attain, prolong, and preserve quality of life. Recent advancements in technology, including computation, robotics, machine learning, communication, and miniaturization of sensors have been used primarily in manufacturing, military, space exploration, and entertainment. However, few efforts have been made to utilize these technologies to enhance the quality of life of people with disabilities. This article offers a perspective of future development in seven emerging areas: translation of research into clinical practice, pervasive assistive technology, cognitive assistive technologies, rehabilitation monitoring and coaching technologies, robotic assisted therapy, and personal mobility and manipulation technology.

iWalker: Toward a Rollator-Mounted Wayfinding System for the Elderly

Research on intelligent walkers aims at helping elderly individuals to maintain their independence in familiar and unfamiliar environments. Several walkers have been developed by researchers at Carnegie Mellon University and the University of Pittsburgh. This article contributes to this research venue by describing the design and initial evaluations of iWalker, a multi-sensor rollator-mounted wayfinding system for the elderly. The primary difference of the proposed navigation aid from other intelligent walkers is that iWalker is assumed to operate in a smart world (SW), a physical space equipped with embedded sensors. By integrating inexpensive sensors into the environment, the cost and complexity of the walker can be reduced.

A prototype power assist wheelchair that provides for obstacle detection and avoidance for those with visual impairments

BackgroundAlmost 10% of all individuals who are legally blind also have a mobility impairment. The majority of these individuals are dependent on others for mobility. The Smart Power Assistance Module (SPAM) for manual wheelchairs is being developed to provide independent mobility for this population.MethodsA prototype of the SPAM has been developed using Yamaha JWII power assist hubs, sonar and infrared rangefinders, and a microprocessor. The prototype limits the user to moving straight forward, straight backward, or turning in place, and increases the resistance of the wheels based on the proximity of obstacles. The result is haptic feedback to the user regarding the environment surrounding the wheelchair.ResultsThe prototype has been evaluated with four blindfolded able-bodied users and one individual who is blind but not mobility impaired. For all individuals, the prototype reduced the number of collisions on a simple navigation task.ConclusionThe prototype demonstrates the feasibility of providing navigation assistance to manual wheelchair users, but several shortcomings of the system were identified to be addressed in a second generation prototype.

Plans and planning in smart homes

In this chapter, we review the use (and uses) of plans and planning in Smart Homes. Plans have several applications within Smart Homes, including: sharing task execution with the homes inhabitants, providing task guidance to inhabitants, and to identifying emergencies. These plans are not necessarily generated automatically, nor are they always represented in a human-readable form. The chapter ends with a discussion of the research issues surrounding the integration of plans and planning into Smart Homes.

Virtual Reality and Computer-Enhanced Training Applied to Wheeled Mobility: An Overview of Work in Pittsburgh

Some aspects of assistive technology can be enhanced by the application of virtual reality. Although virtual simulation offers a range of new possibilities, learning to navigate in a virtual environment is not equivalent to learning to navigate in the real world. Therefore, virtual reality simulation is advocated as a useful preparation for assessment and training within the physical environment. We are engaged in several efforts to develop virtual environments and devices for mobility skills assessment and training, exercise training, and environment assessment. Virtual reality offers wheelchair users a training tool in different risk-free environments without any indoor (e.g., walls, furniture, and stairs) and outdoor (e.g., curb cuts, uneven terrain, and street traffic) physical constraints. Virtual reality technology will probably become more common in the field of assistive technology, especially given the rapid expansion of gaming technology and the continued exponential growth of computing power.

Research in computer access assessment and intervention.

Computer access technology (CAT) allows people who have trouble using a standard computer keyboard, mouse, or monitor to access a computer. CAT is critical for enhancing the educational and vocational opportunities of people with disabilities. Choosing the most appropriate CAT is a collaborative decision-making process involving the consumer, clinician(s), and third party payers. The challenges involved and potential technological solutions are discussed.

Making Better Decisions [Modeling the Assistive Technology Assessment]

AIthough much is known about how people make the decisions in the abstract, as well as in specific fields such as medicine, this knowledge has not yet been applied to the assistive technology (AT) assessment process. This article is an attempt to identify lessons that therapists can apply to their own practice based on what is known about how people make decisions. This article also identifies strategies that clinicians can use to help clients, caregivers, and third-party payers make better decisions. Finally, this article suggests how technology might further improve the decision making process. It should be noted that we are directly familiar with the assessment process for computer access, augmentative communication, electronic aids to daily living, and wheeled mobility, but the same principles of decision science are likely to apply to other disciplines within AT in which a clinician (or team of clinicians) works with a client, the clients caregivers, durable medical equipment (DME) vendors, and third-party payers to identify the most appropriate AT for the client (e.g., orthotics and prosthetics).

Selecting an Appropriate Scan Rate: The “.65 Rule”

Investigators have discovered that the ratio between a users reaction time and an appropriate scan rate for that user is approximately .65, which we refer to as “the .65 rule.” As part of a larger effort to develop software that automatically adapts the configuration of switch access software, data were collected comparing subject performance with a scan rate chosen using the .65 rule and a scan rate chosen by the user. Analysis of the data indicates that for many people, the .65 rule produces a scan rate that is approximately the same as the average switch press time plus 2 standard deviations. Further analysis demonstrates a relationship between the coefficient of variation (the standard deviation divided by the mean) and error rate. If accurate information is available about the mean, standard deviation, and distribution of a clients switch press time, a scan rate can be chosen that will yield a specific error level. If a rigorous statistical approach is impractical, the .65 rule will generally yield a usable scan rate based on mean press time alone.