OREANDA-NEWS. Hitachi Automotive Systems, Ltd. today announced that the company has developed new semi-active suspension electronic control technology that successfully suppresses vehicle vibrations during driving and vehicle position changes while turning on curves by approximately 10%. This has made improvement of both driving comfort and steering stability possible. Such improvements were previously difficult to achieve.

In recent years, many types of technology for the electronic control of automobile driving have been researched with the aim of improving passenger safety and comfort while increasing vehicle steering stability. Issues faced during the development of the steering control system with semi-active suspension were increasing spring flexibility to reduce vehicle vibration to ensure driving comfort while simultaneously improving steering stability, as the ability to keep the auto body parallel during driving maneuvers such as curves decreases as the spring flexibility increases.

Hitachi Automotive Systems developed algorithms to more precisely analyze vehicle vibration and tilt, and also made more flexible spring elastic control of semi-active suspension possible. Specifically, an algorithm that included more parameters than are conventionally used was developed. These parameters quantified factors that affect vehicle vibration such as the rate of changes in acceleration over time to improve driving comfort. To improve steering stability at the same time, the behavior of a vehicle with high steering stability was expressed as a formula, and an algorithm to reconstruct this behavior was developed. Incorporating these two algorithms into the electronic control unit of the semi-active suspension has allowed for smoother driving comfort and improved steering stability.

Normally, seven sensors are used to detect vehicle status in order to control the movement of semi-active suspension. However, Hitachi Automotive Systems has utilized technology to make the highly advanced prediction of vehicle status to enable with only four sensors the offering of the same performance as conventional seven-sensor models. This has also made the reduction of costs possible.

Going forward, Hitachi Automotive Systems will continue with the commercialization of this technology and will offer semi-active suspension electronic control technology that provides smooth driving comfort while also improving steering stability.