Algodoo

トルクモータ型NAFエンジンの例。
ハンドツールで右へ引っ張ると、加速する。
速度は2.4-3.8 m/sの間で増減を繰り返す。
キー操作:無し

Negative Air-Friction Engine with Torque Motor. This is a mechanism to keep constant speed with negative air-friction.

Drug the car to right.

Red box has negative air-friction. Blue box has positive air-friction. Motor has torque to CCW.

At initial state, the red box has more projection length than blue box. The car will be accelerated by negative air-friction. More speed, more negative air-friction generate CW torque. When speed is higher than threshold, the mechanism turn to CW. Now, the blue box has more projection length than red box. The car will be decelerated.