When cornering on a slippery (snowy or icy) road, a vehicle can lose stability and spin out of control or fail to turn.
The VSA system helps the vehicle turn in a stable way by monitoring the vehicle with wheel sensors, steering angle sensors, and lateral G sensors. The VSA analyzes these devices with an electronic control unit (ECU) and automatically controls wheel braking force and engine output with a modulator.
Nissin began making a two-channel (two drive-wheel control) VSA (NK6) in August 1997. Since then Nissin developed the NK11V VSA, a four-channel type that can work with front-wheel drive, rear-wheel drive and four-wheel drive systems. It is the first such system in the world with a built-in pressure sensor. With newly developed miniature solenoid valves, it is 46% lighter than Nissin's previous VSA (NK6). Nissin's current version of VSA is the NK21.