ALPriority, Laser Interceptor and V1 vs Rear Facing Vitronic PoliscanSpeed

[winterbrew]

Here's a comparison test I made yesterday (one car fitted with LI quads, one with ALP quints).










Rear facing Vitronic PoliscanSpeed set up at the base of the 2nd light pole after the exit ramp on the left. Takes photo of the back of the car after it passes.

First run (front cam) is v8.9 Laser Interceptor quad (2 front, 2 rear), v8.14 firmware running at max sensitivity. No alert from the LI, and the V1 picks up the lidar beam approx 110m after passing the camera.

Second run (front cam) is the ALPriority quint (3 rear, 2 front) v4.2.2 firmware. ALPriority alerts before V1 (static type noise), approx 30 - 40m after passing the camera.

3rd run is same as second run, but from rear cam of the car running the ALP. Poliscan and flash unit can just be made out next to base of light pole.

Looking at still photos from the first video, it would appear the Poliscan setup is not on too much of a harsh angle (some can be set to 45 deg across the road), and appears to bet set around 25 - 35 deg for a longer shot, and minimise lidar detection from back scatter from passing traffic.

Sun was directly to the right of the picture shining at right angles across the road, so both sensor types shouldn't have been disadvantaged.

Rear LI sensors were tested on return, and found to be fully functional.

Coming back in the opposite direction of travel (other side of road), the front LI sensors did alert to Poliscan, along with V1, so there does not appear to be a problem with the CPU. Likewise the front ALP sensors alerted on the return trip, but much earlier than the LI.

Conclusion - 4 receiving diodes per head (AL), are better than two (LI) with respects to PoliscanSpeed detection