The Citroën C4 Picasso is the world’s first car to feature an integrated parking space measurement. This Bosch driver assistance system tells the vehicle’s driver whether the prospective parking space is long enough for the car. This gives a greater feeling of safety – especially on congested city streets.

The parking space measurement device in the Citroën C4 Picasso is based on the Bosch parking assistant, which helps drivers avoid shunting other cars and obstacles while parking. Besides the standard four ultrasound sensors on the vehicle front and rear, two extra sensors have been added for parking space measurement, one on either side of the front bumper.

The parking space measurement is easy to operate – on finding a parking space the driver activates the system via a button on the steering wheel. The system establishes which side the space is on by identifying which turn signal is in use. While driving past – at a speed of up to 20 kilometers per hour – the sensor then gauges the space.

The assistant indicates to the driver via the central display whether the gap is big enough for the car, a tight squeeze, or simply too small. The same visual and acoustic signals that feature in the parking assistant then warn the driver of any obstacles. Bosch parking space measurement also works for parking spaces that are on a slight curve. There are many advantages to the new Bosch parking space measurement system. From the viewpoint of drivers, it is an inexpensive addition to the parking assistant. Clearly identifying the length of spaces helps avoid fruitless attempts at parking, thus saving both time and stress.

Automatic measurement also enables smaller spaces to be used that the driver might otherwise reject as being too small. As a result, drivers can concentrate more on traffic and cause less disruption to following vehicles. And, as the parking assistant analyses signals from all ten ultrasound sensors, including the two additional outer sensors integrated into the front bumper, it provides greater protection for the front corners of the vehicle during parking manoeuvres.

Bosch will soon release more functional enhancements for its ultrasound-based parking assistant. By the beginning of 2008, a system will go into series production that will both measure the length of a space and suggest the best way to steer and manoeuvre into the space. A further development level in the same year will make it possible to directly control electrically supported steering – the driver will only need to operate the gas pedal and brake, while the parking assistant will take care of the steering.