Reference, please.
When more sensors don't perform better than less sensors, either your hardware or your software is flawed. Removing a sensor from design because your system doesn't work speaks poorly of your product.
Even following that simplistic logic, if autopilot isn't safe, How could they dare not remove it?
Consider that 99 cameras plus one radar does not make a system perform better if the task is identifying whether there is the color blue in an image. If we add ten thousand radars to this situation it doesn't produce an improvement, in fact, it gets worse, because there is more power being used by the sensors and a lot more complexity.
> Removing a sensor from design because your system doesn't work speaks poorly of your product.
This is a convoluted way of saying that making improvements to things is bad. That is nonsensical.
> Even following that simplistic logic, if autopilot isn't safe, How could they dare not remove it?
They did remove it.
This is very true and it might be where the bad intuition that having multiple unreliable sensors is good is coming from. Multiple noisy readings can be averaged to get a more reliable reading if the distribution of reading errors is normally distributed. You can take ten Norm(0, 10) and average them and the result of that will be a normal distribution with a standard deviation which is lower than the standard deviation of the distribution that we sampled from. See basic statistics for the e
There are a few reasons why this doesn't apply in this case:
1. The measurements aren't going to be of the same thing. At time step t, the state of the world is potentially different from t+1. Since we have one radar sensor averaging the results of the two sensor readings doesn't give us the true position. Kalman filters solve this with a dynamics function so this problem isn't something that is impossible to solve.
2. So lets say we solve it. Even if we did measure the same thing we have another problem. We don't have time to take advantage of the central limit theorem. Yes, multiple noisy readings of the same thing average to the true reading, but since we have only a split second to decide whether to slam on the break to avoid an accident we don't have the capacity to await convergence of the noisy sensor and noisy dynamic function to the true measurement. But lets say we did even though we don't.
3. The radar sensor isn't actually a normal distribution in terms of its noise. It's actually more accurate in certain low visibility conditions because it goes through occlusion, but less accurate given certain environments like going under an underpass. Since the noise isn't normally distributed you don't have the guarantees from statistics which you were hoping to rely on.
The factual content in your comment is decisively lacking.
Careless of you, I think.