By that logic a speedometer is an anti pattern and your car should just send up an alert when you're speeding... since when is getting accurate real-time information a bad thing?
The only reason we don’t have that yet is because the car doesn’t know the speed limit everywhere all the time.
* when speed restricted by equipment (trailer, temporary spare, etc)
* when observing advisory speeds
* when observing minimum speed requirements
* as a reference for judging appropriate speeds under inclement conditions
* as a reference for judging appropriate acceleration/deceleration rates when entering/exiting the roadway
A single number in isolation is rarely useful. Graphs with trends are useful. Alerts are useful.
The only reason we don't have alert based speeds is because it can't get all the necessary information to make a useful alert, so we compromise by telling you the number.
> as a reference for judging appropriate acceleration/deceleration rates when entering/exiting the roadway
A perfect example of why a graph would be ideal here, not a single number.
> perfect example of why a graph would be ideal
A gauge chart, maybe? :D
But seriously, if we have a system that appropriately judges everything on my laundry list above, you probably won't need an alert system anymore because the cars will be self-driving.
The vehicle has a camera that looks out for speed limit signs, and then updates a little icon on the instrument cluster with the current speed limit. It works very well.