Design of Air-Jet Flow Frame to Control Bug’s Flight Path to Prevent Collision on LIDAR Covers

Environmental factors such as vibration, high air temperature, rain, haze conditions, or insects’ debris on the sensor may negatively impact the performance of light detection and ranging (LIDAR) sensor. For instance, at high velocity, especially on summer nights, the bugs strike on the LIDAR cover surface and accumulate over time, blocking the sensor visibility. As a result, the sensor measurement becomes obscured by insects splashing on the LIDAR cover, resulting in a critical loss of performance in LIDAR sensor readings. One approach to resolve this problem is to keep insects away from hitting the sensor cover. To change the insects’ flight path, it is possible to implement a non-invasive method such as applying high momentum air-jet adjacent to the LIDAR cover to deflect the bugs away from the surface. This non-invasive mechanism can control the airflow near the front surface of the sensor to prevent insect collision on the surface. This study designed and fabricated a custom-made air-jet to modify the airflow trajectory on the sensor’s front surface and used nylon pellets as insects. With this design, it is possible to control the resultant upstream airflow before impacting the LIDAR surface, consequently preventing insects or other particles from colliding the sensor cover. The resulting upstream flow depends on the air-jet flow and free stream velocity ahead of the sensor. Highspeed imaging studies have been applied to determine the effectiveness of the air-jet design in altering the nylon pellets’ flight. High-speed imaging shows how different operating conditions affect the nylon pellets path on LIDAR cover. The controlling parameters in this experimental study are free stream air velocity and orientation of air-jet velocity.