The ARM Increases Independence for People with Disabilities

I have seen many movies with robots’ manipulative arms moving an infinite number of ways. Their strength enables them to crush an enemy’s wrist, pick up tools, pull down walls, and operate machines. Oddly, robots in movies are often on the side of evil and usually defeated in the end. Still, audiences love this science fiction, and many of us dream of having robots of our own to free us from drudgery.

Now engineers at Exact Dynamics (www.exactdynamics.nl) have really developed an Assistant Robot Manipulator (ARM) to increase all aspects of independence for a person with a disability.

ARM is a mobile rehabilitation robot mounted on an electric wheelchair. It assists people with severe upper limb disabilities. It compensates for a lost arm and hand, or just the loss of use in either. Users can perform tasks at home, work, and outdoors. The domestic chores include eating and drinking, preparing meals, using a microwave, taking medicines, scratching an itchy body part, electrical shaving, opening doors, watering plants, operating light switches, and inserting a tape into a VCR. Occupational tasks include inserting a disk in a computer, operating a computer, drawing, and making telephone calls. For leisure, there is playing chess, painting, and turning a page of a book. When shopping, the user can take objects from an upper shelf.

Using an input device, the manipulator can firmly grasp objects with its gripper, the most versatile part of the ARM. The gripper has clamping force of 2 kg, and three-hinged fingertips covered with anti-slip material. The user controls the clamp force. In case of emergency, the gripper easily opens manually without damaging it. The maximum spread between the fingers is 9 cm (3.5″).

An input-device is selected based on the capabilities of the user. Input-devices used to operate the ARM are a joystick on the wheelchair or a separate/second joystick; a keypad with 16 buttons (coming in four sizes: mini, normal, large, jumbo); switches/buttons (e.g., head-switches, foot-switches); and a single switch. In transparent mode, an IBM compatible PC can control the ARM. Additional input devices are under development. Exact Dynamics’s GertWillem Römer says that “first tests in voice control of the ARM have been carried out. The results were encouraging.” I suggest the company look into eye gaze technology, as well.

The mounting arrangement of the ARM to the wheelchair has not been standardized to all types of wheelchairs available on the market; therefore users make a personalized specific adaptation to each type. The ARM can be mounted to the left or to the right side of the wheelchair. Right or left fixation depends on users’ preference and orientation capacity and on available space at the right or left side of the wheelchair. To learn more specifics contact the company.

When not in use, the ARM can be folded in next to the wheelchair.

What do consumers with disabilities think of the ARM? Amputee Janice Wilson says enthusiastically, “I see it as an essential tool to employment for people with disabilities.” She saw it demonstrated at the CSUN Conference in March at LAX International Airport. She sees it as benefiting individuals who want to live independently.

Potential users can benefit the most from the ARM by showing they understand the device; are highly motivated to use aids, crave independence, and have sight.

The ARM can be controlled in two modes: “Carthesian” and “joint,” both allowing efficient and effective manipulation of objects. The display unit gives information about the status of ARM. It consists of a 5×7 LED matrix and a buzzer in a box of 68×16x116 mm, and weighs 100 grams (0.2 lb). When using the ARM, the display screen shows which operation mode ARM is in. When a dangerous situation or error occur the buzzer beeps. The ARM is connected to the batteries of the wheelchair (24VDC, 1A nominal, 3A peak).

ARM user David Smith said it took him three hours to learn to use the ARM comfortably. However, he says using it is a lifetime of learning experiences.

Unfortunately for all of its value, the ARM costs $30,000. This price makes it prohibitive for hundreds of thousands of people who can benefit from it. There are no government subsidies for buying it. Private insurance agencies tell me their companies would probably pay for the device if it is warranted for work.

The ARM offers many employment opportunities for people with disabilities, and they should investigate its possibilities for themselves. The Pentagon and Department of Veterans Affairs should look at it as a tool for amputees.

John M. Williams has been writing about assistive technology for more than 25 years. A sample of his book Assistive Technologies: Creating a Universe of Opportunities for People with Disabilities can be seen at www.atn-ctcf.org.