Sumitomo Electric Industries has launched a pedestrian detector for driving safety support systems (DSSS) to reduce traffic accidents. This detector is claimed to have robustness against variable environmental conditions owing to the use of a 24 GHz-band millimetre-wave radar technology along with high accuracy in pedestrian detection through company’s proprietary algorithm and a wide detection area.
For the purpose of reducing traffic accidents, Sumitomo Electric has developed DSSS based on vehicle-infrastructure integration. As one of the typical subsystems/services of DSSS, prefectural police departments and automakers have cooperatively operated 'Right-turn Collision Prevention System/Right-turn Crossing Recognition Enhancement' system. This service is enabled by a wireless roadside unit that provides information on the presence of pedestrians on the crosswalk and oncoming vehicles detected by roadside sensors to alert the driver in a vehicle turning right at an intersection by sending warnings through display indications and sound. In addition to wireless roadside units and vehicle detectors already launched on the market, Sumitomo Electric has newly released a pedestrian detector and had started shipping in March 2018. The detector has been delivered to five prefectural police departments in Japan, including the Osaka Prefectural Police Department.
The number of traffic fatalities has been decreasing in Japan year by year (3,694 in 2017). While elderly adults (65 and older) account for more than half of the death toll, a drastic reduction has not been seen for this group.
Working of the DSSS from Sumitomo Electric
Sumitomo explains that the millimetre-wave radar transmits a radio wave and receives its reflection from an object to measure the distance between itself and the object. The algorithm incorporated into the product tracks and predicts the movement of pedestrians by analyzing characteristic information conveyed by the reflected wave. This technique enables the products to detect pedestrians behind passing vehicles.
One difficult challenge for a millimetre-wave radar is to achieve incompatible tasks of covering a wide range in close proximity and extending the detectable distance. Sumitomo claims to have developed multiple-channel antennas and a signal processing technique, enabling a wide detection area for the detector installed on a pedestrian signal pole near the crosswalk. The product is said to be able to detect pedestrians both in the waiting area in close proximity and those on the crosswalk, whether the crosswalk is small or large. The company claims that owing to this feature, the detector can be installed in a greater variety of locations.