Description

What does “Shibetsu” in Shibetsu Fin mean?

“Shibetsu” is the name of a place in Hokkaido where Toyota Motor Corporation has a proving ground. In winter, temperatures can drop below minus 30 degrees Celsius, and dozens of centimeters of snow can accumulate overnight. In this harsh environment, Toyota has established a vast 930-hectare proving ground, equivalent to approximately 200 Tokyo Domes, where it has honed its technology for over 40 years. Taking advantage of the harsh environment and vast grounds, the Shibetsu proving ground conducts “cold weather performance tests” and “ultra-high-speed driving performance tests.”

The 10km first circuit, where ultra-high-speed driving performance tests exceeding 250km/h are conducted, has a 4km straight section, and due to the curvature of the Earth, the center of this straight section is 24cm higher than the ends. This 4km straight section is the place where vibrations at the 0.01Hz level were observed, which led to the creation of the “Shibetsu Fin,” and the Shibetsu Fin could not have been developed without the Shibetsu test site.

Three types of stability you can get with Shibetsu fins

By simply adding custom fins to the underside of the vehicle, the airflow beneath and behind the vehicle is streamlined, improving driving stability and enhancing driving performance.

POINT01

The source of the instability is a fluctuation of less than one time per second.

It was discovered that what disrupts the desired stability is not the shaking that occurs more than once per second, which can be perceived as a “shake,” but rather the “slow shaking” that occurs less than once per second, which is perceived as a “wobble” or “fluctuation.”

POINT02

It was discovered that what disrupts the desired stability is not the shaking that occurs more than once per second, which can be perceived as a “shake,” but rather the “slow shaking” that occurs less than once per second, which is perceived as a “wobble” or “fluctuation.”

It was found that the “slow shaking” (not only due to road surface disturbances) is largely caused by turbulence in the airflow around the vehicle, which creates large vortices and a significant pressure difference on the left and right sides of the rear of the vehicle.

POINT03

Shibetsu fins can eliminate the pressure difference between the left and right sides!

The Shibetsu fins ensure stability by converting the energy of large vortices around the vehicle into the energy of smaller vortex clusters, thereby reducing the pressure difference between the left and right sides of the rear of the vehicle.。

Construction details

Attach the fins to 16 locations on the underside of the vehicle.