Competitive Wheelchairs and Prosthetic Limbs Active in the Paralympic Games

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Finally the 2020 Olympic and Paralympic Year

Wheelchairs and artificial limbs for competitions that are active in the Paralympics

With the growing interest in sports for the disabled, the development of sports equipment for the disabled, such as wheelchairs, has progressed, and the functions have become more sophisticated due to the diversification of materials and advances in processing technology. At the 2020 Tokyo Paralympics, I would like to pay attention to the wheelchairs and artificial limbs for competition that play an active role as the legs of the athletes.

Wheelchair for athletics speeding up

Wheelchairs for competitions have a shape different from that of general wheelchairs used in daily life, and have evolved according to the characteristics of each competition. For example, a wheelchair for athletics called a "racer" used in wheelchair marathons (Photo 1). In addition to light and durable aluminum alloys and titanium alloys, carbon fiber, which is said to have a high vibration absorption rate, is also used for the car body to enable high-speed driving. In order to further reduce air resistance, the mainstream is three wheels with the front wheels protruding forward, and the athletes fold their legs and keep their low posture while hitting the hand rim (the part that they hold when they are hand-kneaded) from above. Tell to. As a result, the speed has been increased to 30 km / h for trucks and 50-70 km / h for marathon downhills.

Wheelchair for athletics

Made to order according to the competition

On the other hand, the angle of the wheels is a big difference between the wheelchairs for competitions such as tennis, basketball, and raccoon. The tires of a general wheelchair are perpendicular to the ground, but for competition, the tires tilt in a "H" shape. This is because it is designed to make small turns according to movements such as turns and sprints, and especially for tennis, which requires agile movement, the inclination is the largest and about 20 degrees compared to other competitions. There is (Photo 2). In addition, small wheels are attached to the front and back of the wheelchair so that it will not fall even if you bend your body to the back and serve, which is a unique device for tennis.

For competitions such as basketball and rugby where players come into close contact with each other, it is characterized by having a defensive bumper on the forefoot. Among them, rugby wheelchairs are ruggedly built like armored cars, and there are two types: offensive type and defensive type. The offensive type has a compact and rounded shape so as not to get caught in the opponent's defense, and the defensive type has a bumper protruding to block the opponent's movement. If you can distinguish offense and defense in the form of a wheelchair, watching the Tokyo Paralympics will be more interesting.

Wheelchair for tennis

3D printers can also be used for artificial limbs

Many of the prosthetic limbs for competition have a unique shape as symbolized by the prosthesis for athletics, which is shaped like a bent plate (Photo 3). This is because it is designed to replace the legs of athletes and enable movements such as "running," "jumping," and "kogu." Therefore, the materials are also evolving, and carbon fiber reinforced resin, which is also used for aircraft, is used for the leaf springs of prostheses for athletics, which momentarily apply a load of 8 times or more of the body weight when running. By using a material with repulsive force and propulsive force, it became possible not only to run but also to jump. Its superhuman performance is entertaining to the viewer, but there are also voices asking the advantage of the prosthesis when it comes to competing with healthy people.

In the case of artificial limbs, the performance and materials differ depending on the characteristics of the competition, but when installing any artificial limb, a part called a "socket" is required. The shape of this part is different for each user, and it is necessary to make fine adjustments to get a perfect fit, so the use of 3D printers is being considered. In addition, the latest technology is expected to be applied to sports for people with disabilities in myoelectric prosthetic hands and legs with the development of robot-related technology.

Prosthesis for athletics