smartmicro radar sensors offer highly innovative, patented fail-safe features. By means of integrated self-calibration and self-diagnosis functions, such as blindness and rain detection, misalignment detection, and interference suppression, they ensure dependable operation.
The fail-safe features play a crucial role in the reliability of the sensor detection and in reporting error conditions to the higher system level. This allows for the traffic management system real-time awareness about any issues, enabling it to switch to a dedicated fail-safe mode and activate an alternate plan.
smartmicro's fail-safe features significantly enhance the reliability of the traffic management system and, thus, improve road traffic safety.
Sensor blind detection
While radar sensors are usually the “last sensor standing” and work under adverse weather conditions such as heavy rain and snow, there are rare situations that can still reduce detection performance.
For example, a blizzard may cause a situation in which the sensor is covered with a layer of snow or ice, blocking detection.
The feature “sensor blind detection” is part of the built-in self-diagnose of our sensors’ software. When such a condition is detected, the sensor indicates this to the traffic management system. The intersection controller can then enter into a time based mode, where no detection is needed. The sensor automatically returns to normal operation once the condition is no longer present.
Rain detection
One of the many advantages that smartmicro radars offer are their patented fail-safe features, including the detection of weather conditions – like heavy rain - that may impact the sensor’s performance.
smartmicro's technology goes beyond just detecting rain or snow – it can measure even the intensity of the precipitation and its influence on detection performance. Whereas light rain has practically no impact on the performance of our detection system, heavy rain can lead to reduced detection range.
smartmicro sensors are designed to detect and report heavy rain that leads to such reduced detection range, enabling the traffic management system to take appropriate actions.
Interference Detection and Mitigation
There are multiple possible sources for frequency interference that can disturb a traffic sensor’s performance, such as misconfigured or misplaced other traffic sensors or the situation in which multiple devices are reusing the same channel. Enforcement systems using radars temporarily can also cause inference, and the most interference is usually caused by passing cars using automotive radars in the same band.
This is challenging for the sensor because inference increases the noise floor, which can reduce the effective range of the sensor.
smartmicro’s sensors detect the presence of inference sources by recognizing areas of abnormal energy within the echo signal. They feature sophisticated interference suppression techniques, suppressing the influence of the interference so that even under such conditions the radar can detect traffic. If the interference level is too high, the radars report the condition to the traffic controller to switch to timed mode.
Misalignment Detection
What happens when sensors or the pole that they are mounted on are misaligned due to a storm or accident? smartmicro fail-safe features offer an innovative method for our sensors to successfully detect errors in case of misalignment.
At the configuration and installation time, the sensor’s exact position is stored. The saved position is then continuously compared to the actual position of the sensor. In case the sensor gets misaligned due to an impact, this deviation is reported to the traffic management system.