I use ACC a lot. It works perfectly while in traffic - it follows a car in front of me, if it stops - I stop as well, it starts to move - I click "Res+" and it keeps following. However I've noticed a strange feature - if I am on ACC, and on _empty_ road - it follows the speed that is set. But say there is a street light approaching, and there is a car _stopped_ at the light - ACC will ignore it (car icon on ACC still a silhouette) and car approaching it without reducing speed. Then when we are really very close car starts to flash "BRAKE" and I have no nerves to keep testing - I hit the brake. Means car knows there is something in front of it, but ACC is ignoring it. Does that mean that ACC programmed to "see" only moving objects?
I find it a strange and unsafe solution from engineering point of view. If I am on an empty highway driving on ACC for hours and there is a construction truck stopped ahead - I'd prefer that car will slow down gradually and stop instead of waking me up by the sound of a crash.
Some folks consider it unsafe to not pay attention while operating a motor vehicle. The manual clearly warns that these features may fail to operate as designed, without notice.
Most radar cruise systems are programmed to ignore stationary cars over a certain speed. If they didnt a lot of them would just never move.
In this case the car is operating as designed. I too have clearly noted that as my car is approaching a stopped car in my lane, on a straight no curve bit of road, it will gladly slam into the stopped car. If that car is moving at all the radar will lock onto it. But just sitting in my lane, stopped perhaps to make a right turn, it will not lock onto the stopped car. Of course I'm paying attention and I always have to take action in these cases. I believe the programming is at fault. I also it is following the rules Honda has set forth. The rules are not good in this case.
I believe this is a problem with 'all' automatic driving systems. Radar cannot tell the difference between a car, a wall, or an overpass. The systems are programmed to ignore stationary objects. I have heard stories that Tesla has a similar problem. Rumor is Tesla has problems with following a car that changes lanes to pass a stopped bus. The Tesla will stay in lane, and slam into the bus.
Regardless how car should be operated If the system _can_ be designed in a safer way It _should_ be designed in a safer way However I am sure that I am not smarter than a dozen Honda engineers who do that for living And there was a reason to make it this way I am just curios - why? Think Evfred is right, it has to filter background non-moving objects from moving traffic.
That is why Tesla puts so many cameras on their cars instead of more radar and lidar, along with a higher-powered computer than most. Vision and processing (whether human brain or computer) are required to actually determine what things in front of you are. Radar/lidar can only say "there's something reflective about X meters away" and the computer or human behind the radar/lidar has to guess what that something might be. Besides, radar and lidar are never going to enable autonomous driving. A radar can't tell the color of the light at an intersection.
Yes, it is operating as designed. It is up to the operator to understand the capabilities and limitations of these features. They won’t protect an operator who is asleep at the wheel and, if they malfunction or fail to perform as expected, an alert operator will need to take action.