The inspiration originated from the structure of "Proa", with ringent trailing wheels to maintain vehicle body's stability.
他的概念来自于三点式帆船,通过两个张开的后轮来保持车身的稳定性。
英语百科
Trailing wheel
(重定向自Trailing wheels)
On a steam locomotive, a trailing wheel or trailing axle is generally an unpowered wheel or axle (wheelset) located behind the driving wheels. The axle of the trailing wheels is usually located in a trailing truck. On some large locomotives, a booster engine was mounted on the trailing truck to provide extra tractive effort when starting a heavy train and at low speeds on gradients.