• Back
• Next

日本語

Typical electric go-karts have a drawback specific to the electric type: namely, the battery problem. Currently, the heavy batteries are removed from the go-kart by an attendant and carried to an electrical facility for charging. This led the research team to consider the challenge, "When the go-kart returns to the boarding area after traveling on the track, might it be possible to charge the batteries quickly before the next departure without removing them?" One early thought was to attach and remove a charging cable to and from the go-kart. However, the cables for quick charging are thick and heavy, making them too cumbersome for easy regular use. Therefore, we came up with the idea of wireless charging. If we could lay electrode plates on the road surface of the go-kart stopping area and wirelessly transmit power to the go-kart from there, there would be no need to handle heavy cables.

The laboratory has since commenced this research on wirelessly charging the go-karts in Nonhoi Park. The key to successful quick charging is the efficient transfer of large amounts of power. Focusing on hyperbolic geometry, a special kind of plane geometry born in Europe in the 19th century, as the key to high efficiency, the design and prototyping of a wireless quick charging system that make full use of hyperbolic geometry is already underway. Such hi-tech go-karts could become a social implementation model for future electric vehicles. The future go-karts will make children’s dreams come true with them as they take flight.

"We faced a major hurdle when thinking about how to efficiently deliver energy from the power source to the go-kart batteries wirelessly. We found that the wireless electrodes and batteries which we were trying to mount on the go-kart had a completely different high-frequency impedance (ratio of voltage to current). We fumbled our way through various different methods at first, thinking that there had to be some way for us to overcome this barrier. Finally, we realized that this problem came down to planar geometry, which deals with how to bring two points that are far apart from each other on the plane closer together. At the same time, our laboratory proposed an attempt to utilize hyperbolic geometry, a 19th century European discovery, to solve contemporary problems. (References [1] to [9]).

We call this attempt the ‘analog renaissance’. In hyperbolic geometry, if we try to connect two points on a plane by the shortest distance, the path is not always a straight line. The key to solving the problem was the hyperbolic distance metric concept, advocated by French mathematician Henri Poincaré. New solutions are created by incorporating counter-intuitive geometric ideas into system design. We will showcase this new solution at Toyohashi Nonhoi Park." said Research Team Leader, Project Research Associate Minoru Mizutani, the research team leader. We are grateful that he could share such fascinating insights about this research.

The goal of the research team members is to implement the world’s first future-vehicle technology in Toyohashi at Nonhoi Park. Their hope is that many people will be thrilled by the experience of this new go-kart, and that it will spread to amusement and theme parks not only in Japan but all around the world.