Automatic Emergency Braking
This is actually a more important problem and hard problem than it seems.
If you draw your confusion matrix, you have two bad scenarios:
- Too loose threshold: You don’t need to break, but AEB is toggled anyways False Positives
- Too strict threshold: REALLY BAD. You have to break, but your AEB doesn’t toggle (you kill a pedestrian) False Negatives
Good AEB systems are really tuned well to find the perfect balance. https://docs.google.com/presentation/d/1HQSLPLE-fZ3EN-9PyqMd7-ti7JSLKL7qlrouGFEprU0/edit#slide=id.p11
Nowadays, AEB systems in cars are mandatory to promote safety.
Simple AEB using TTC
The simplest way to do AEB is calculating TTC (Time-to-Collision), where
where is the instantaneous range measurements and is the current range rates. The operator is defined as .
- by using the current measurements from the
- by mapping the vehicle’s current longitudinal velocity onto each scan beam’s angle by using , where is the forward speed in the vehicle’s frame of reference (obtained from
Odometrymessage), and is the beam angle obtained from