Clean Radar Thanks to Piezoelectric Bellows

Clean Radar Thanks to Piezoelectric Bellows

Lidar, camera, and infrared: contemporary automobiles are equipped with a plethora of sensors. A start-up has devised a way for maintaining the cleanliness of these sensors.

Anyone who drives a contemporary automobile on a regular basis is familiar with warnings such as “Caution, distance radar/blind spot assistance is not operational, camera/radar is filthy!” Because accurate data from cameras, infrared cameras, and lidar systems (light detection and ranging – optical distance and speed measurement) is required for the aid systems that now enable semi-autonomous driving to operate well.

Later on, completely automated driving should be achievable at the greatest degree of autonomy, Level 5. Dirty sensors are a rather common stumbling block on the road to fully autonomous driving. However, the simpler the problem, the more difficult it might be to discover a trustworthy solution. ActaJet is a sensor cleaning method created by the US start-up Actasys.

Actasys ActaJet sensor cleaning

Actasys is headquartered in New York’s Brooklyn neighborhood. Miles Flamenbaum, the company’s CEO, also traveled extensively between the German automobile metropolises of Munich and Stuttgart throughout the development process. He commuted by train and was ecstatic at how effectively and quickly the link functioned — it was believed to be far better than the US rail system. From a German perspective, one may anticipate he would be dissatisfied with the railroad’s reliability under his system.

Flamenbaum is now pushing Actasys’ ActaJet sensor cleaning device, which is based on the notion of a forceful jet of air pressure. When an excessive number of raindrops adhere to a sensor, the cleaner sweeps them away using its air pressure nozzles. Actasys employs heated air through the same nozzle when snow and ice cover the sensor, and compressed air is combined with water when muck and mud obscure the sensor’s vision.

Bellows made of piezoelectric material

The Actasys cleaning system is technically based on an actuator cartridge, which in this case is comprised of piezoelectrically powered bellows. It provides a forceful and consistent air flow without the need of rotating fans or pumps due to the high-frequency suction and expulsion of air. The disk-shaped bellows are only a few millimeters thick and have a diameter somewhat smaller than a standard compact disc.

When the sensor detects pollution, it activates the bellows. Actasys has thus far demonstrated just prototypes of their compressed air bellows; the inventors are still working on a system that incorporates water injection. Flamenbaum explains the issue: if the water is applied to the sensors via standard windshield wiper nozzles, the water usage on a day with a lot of spray and debris is around 20 liters.

Actasys ActaJet sensor cleaning

Due to the fact that the automobile would therefore need to fit big tanks that would still require regular refilling, this approach would be impractical for everyday usage. However, because to its piezoelectric bellows, it can distribute water far more precisely than windshield wiper nozzles, greatly reducing water usage, Flamenbaum reports.

How much water he requires each day, how he intends to store it, and how he intends to transfer it to the nozzles are all still under construction, which is why Flamenbaum is withholding specifics. However, because to its piezoelectric bellows, it can distribute water far more precisely than windshield wiper nozzles, greatly reducing water usage, Flamenbaum reports.

How much water he requires each day, how he intends to store it, and how he intends to transfer it to the nozzles are all still under construction, which is why Flamenbaum is withholding specifics. However, because to its piezoelectric bellows, it can distribute water far more precisely than windshield wiper nozzles, greatly reducing water usage, Flamenbaum reports. How much water he requires each day, how he intends to store it, and how he intends to transfer it to the nozzles are all still under construction, which is why Flamenbaum is withholding specifics.

ActaJet cleaning has previously been demonstrated to perform successfully in laboratory demonstrations of the compressed air function: the nozzles clean the sensor surfaces with pinpoint accuracy and minimal noise. Raindrops have a detrimental effect on all sensors, but particularly the infrared camera, which provides almost no useful photos. Also, the specialists created a system for determining whether the sensors are clean again – this was deemed a significant problem.

Actasys forecasts that the market for sensor cleaning systems will reach roughly 80 billion dollars (approximately 71 billion euros) by 2030, with 630 million lidar systems alone estimated to be supplied. According to the start-own up’s assertions, it is already collaborating with big automakers — among its backers is the Volvo Cars Tech Fund.

Also, major component suppliers (Tier 1/Level 1) and Israeli venture capital firm Next Gear Ventures, which focuses on intelligent transportation, are likely to join. Actasys’ next step is to optimize the control systems for their ActaJet cleaning technology, for example, by including data on weather conditions and fleet utilization. Actasys, however, has not yet specified a precise market launch date.