What is Hill Start Assist?
Hill Start Assist is a driver assistance system. It comes into play when the vehicle standing on the slope has to drive off again.
Usually, the driver needs to take off the vehicle again; that stops on the slope. However, it starts to descend instead of going ahead because the driver takes his foot off the brake pedal to press the accelerator pedal. During this transition period, as the driver takes his foot off the brake pedal, the brake system releases the pressure applied to the wheels. So, the vehicle starts to descend again. This may prove dangerous in two ways.
Firstly, it endangers the life of the people traveling in that particular car. Secondly, such a descending vehicle may strike the vehicle standing exactly at the back. Hill start assist helps to avoid such a dangerous situation. This system resists the vehicle descend in such a situation. It also holds the vehicle at the same location even after the driver releases the brake pedal. This helps the driver to take off smoothly and without any danger.
Working of Hill start assist:
Earlier, such a facility was available only on the vehicles with an automatic or semi-automatic transmission. But, nowadays vehicles having a manual transmission could also have it. This is because Hill start assist now works with the help of the Electronic Stability Program (ESP). ESP & acceleration sensor work in unison. They can detect the situation of vehicle stoppage on the slope.
In such a situation, when the driver releases the brake pedal; the system still maintains the brake pressure on the wheels for almost two seconds. Thus, it enables the driver to start off again smoothly.
Typically, Hill assist comes into action for every slope greater than 3%.