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Failure modes of radar sensor

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Hi everyone,

I got my hands on a Bosch mid-range radar (MRR) sensor that I believe belonged to a model S a while back. Now I'm working on a school project where we try to get the sensor to fail (i.e., output wrong or unusable data). Those of us involved in the project have defined a goal of understanding more about why radar fails in general but also what aspects of Bosch's specific sensor design might contribute to a failure.

So far, some preliminary research has revealed the following common failure types for automotive radars:

- External RF noise
- Ghost targets (e.g., multiple reflections from the same object resulting in targets with integer multiples of speed/distance)
- Obscurants on the sensor (e.g., snow, mud)

If anyone knows anything about other failure modes that exist, especially for Bosch radars and sensors, it would be interesting to discuss them on this thread.

Thanks!!
 
Think of what the RADAR is actually doing, it is measuring the reflections of radio waves over relatively short distances using a very low power transmitter.

Here are some things that may impact it
  • Any RF that may have a primary or harmonic signal in the receiver's range
  • Any RF that is near the primary frequency, but at a significant power level
  • Reflections off of anything and everything
  • Angles of reflections are important to consider as well.
  • misalignment of transmitter and/or receiver
One of the things that you have to remember is that the software in the unit is relatively complex. It is going to try to cancel a lot of the noise out before you see it. So sometimes you may even see artifacts from the software.
Also, remember the RADAR is one of many sensors that are helping make decisions.

But honestly, you shouldn't consider a sensor failure as a catastrophic event. How many times have you driven down the road, seen something, but when you looked back, it wasn't what you thought it was? The eyes plays tricks as well. Someone gave you stereoscopic vision with a significantly powerful DSP resting between the two sensors. If you listen to most people, people couldn't drive a car.
 
Thanks for your feedback. We have considered a few different types of reflections that could cause false targets, as well as misalignment and RF noise. At this point we're looking for rare types of failures that we might be able to provoke and gain insight into how best mitigate them.