Engineering a Better Quality of Life

The motorized wheelchair 

Before the Second World War, no one had had much success developing an electric wheelchair. Engineers had been putting motors on standard folding wheelchairs, but their attempts did not work very well. The modified chairs were impractical and dangerous – no one wanted unreliable chairs wreaking havoc in hospital hallways. Some even thought there was no need for motorized wheelchairs at all.

But World War II changed everything. The war produced a new kind of veteran. The introduction of penicillin treatments allowed soldiers to survive injuries that previously would have killed them. This also meant that increasing numbers of para- and quadriplegic veterans were returning home to deal with the reality of living with paralysis. Manual wheelchairs were no longer adequate.

NRC's George Klein and his team created the first practical motorized wheelchair at NRC in the 1950s.

NRC's George Klein took on the task of creating a useable electric wheelchair to meet the needs of these new veterans. He fixed the problems with earlier designs by increasing the electric drive's voltage and replacing the single drive with two separate ones. These were dramatic improvements, but he continued to perfect the design. 

Throughout the entire process, Klein's team worked closely with the patients that would eventually use the chairs. Klein wanted to make sure the end product would be useful for them. Patient tests, suggestions and feedback guided the designers. 

For example, one patient's movement was restricted to his head, so a control system was developed to allow the man to operate the chair with pressure from his cheek instead of his hands. After some practice, the man could control the chair without assistance, giving him the chance to experience an exciting new independence.

The end result of Klein's efforts was not only the world's first truly practical electric wheelchair – an invention that would change the lives of people with severe disabilities – but also an entirely new way of developing medical aids. By working closely with the wheelchair's future users to design the device, Klein pioneered the field of rehabilitation engineering and discovered the remarkable strength of the human spirit along the way.

The artificial pacemaker                 

It was while studying hypothermia at NRC that John A. Hopps acquired the high-frequency heating and microwave skills that would lead him to make the first artificial cardiac pacemaker – a device that would save thousands of lives.

In 1949, physicians were using extreme cold to slow down heart rate and make open heart surgery possible, but they could not figure out how to safely restart a heart if it were to stop during surgery. Enter Hopps, who accidentally discovered that a "cooled" heart could be restarted without damage by using a mild electrical stimulus. The discovery led to the creation of the first artificial pacemaker to stop ventricular fibrillation (a disruption in the heartbeat).

Dr. Hopps testing an early pacemaker prototype.

One year later, a model of the pacemaker was revealed to the public. It measured 30cm (about one foot) long – much too big to be implanted in the body like today's pacemakers. The 1950s pacemaker used vacuum tubes to generate pulses and was powered by 60Hz household current. The transvenous catheter electrodes used in the first model are still found in today's pacemakers.

Over the years, advancements in battery and transistor technology allowed the pacemaker to become increasingly small, until it could be implanted into humans. This happened for the first time in 1957 when one of the devices was put into the chest of a Swedish man.

For years, scientists continued to refine pacemaker technology. In 1963, concern about the hazards of batteries running down while in the body led another NRC engineer, O.Z. Roy, to look for a way to run the pacemaker off the energy of the human body itself. In 1965, the first biological pacemaker was created.

When he received his own pacemaker in 1984, John Hopps experienced first-hand how important this invention was for saving lives.

Through the wheelchair and the pacemaker, NRC's scientists and engineers have improved the lives of countless people around the world and continued the NRC tradition of innovative medical research.

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