The man-in-wheel car was invented more than 100 years ago

During the period 1860 - 1930, the monowheel was frequently mentioned as a new type of transport despite many design problems.

Richard C. Hemmings' monowheel (left) and Professor EJ Christie's 14-foot "monster" unicycle in 1923. Photo: Rare Historical Photos

In 1869, French inventor Richard C. Hemmings patented the first monowheel, which looked like a giant wheel with a seat inside. However, it actually had two wheels. Under the seat was a second, smaller wheel. The rider would pedal to move the smaller wheel, which would move the larger wheel as well. At the time, the monowheel was considered an unwieldy and impractical means of transportation for the average person.

By the early 20th century, inventors were experimenting with actual motor-powered unicycles. Some designers even built vehicles with airplane propellers attached to the front to aid in movement. None of these designs made it into mass production.

In the 1930s, science magazines began to feature designs for car-like unicycles with metal frames that could carry several people.

The most famous design of this strange vehicle is probably the one created by Dr. JA Purves in 1932. This motorized vehicle, called the Dynasphere, could reach a maximum speed of 25 - 30 km/h. Purves believed that the unicycle was the simplest possible motorized vehicle. However, the Dynasphere was never as successful as he had hoped. It was not a reliable vehicle, could only carry one passenger and the driver, and had many insurmountable design problems.

Dynasphere Unicycle. Video: British Pathé

A monowheel differs from a unicycle because the rider sits inside the wheel, not on top or outside it, and it acts like a giant ball bearing. The rider and motor are anchored to the inner wheel, while the motor propels the outer wheel forward.

Monowheels can stay upright using the same principles as gyroscopes. As long as there is an external force creating motion, in this case a motor (although some are pedal-powered), the vehicle will move.

Monowheels are difficult to steer because they have no other wheels to support them, and their somewhat odd design also makes handling tricky. Riders often want to keep their feet close to the ground to keep the vehicle from falling over.

In addition, if the vehicle is equipped with a powerful engine, it is difficult to make full use of the engine's power with this design. The lack of stability when not moving forward also makes braking extremely difficult.

Overall, there are a number of inherent design issues that inventors need to address, including poor visibility, instability, poor steering, and the “gerbil” phenomenon. This can occur when the driver accelerates or brakes too quickly, causing the force to exceed the force of gravity holding the driver at the bottom of the wheel. The driver then risks spinning inside the wheel like a gerbil, a pet, when it suddenly stops running while the wheel continues to spin.

Ultimately, monowheels never caught on. People still build and ride them today, but usually just for fun.