Re: Speed limiters

On 7/7/2024 3:51 PM, KevinJ93 wrote:

On 7/7/24 9:57 AM, Don Y wrote:

On 7/7/2024 9:08 AM, KevinJ93 wrote:

On 7/7/24 9:00 AM, Don Y wrote:
<....>

Nothing for the cruise control touches the brakes.  It relies on the engine to
slow the vehicle.
>
There are newer "collision avoidance" systems that will actively brake
if they sense you're approaching an object with which you may collide.
>
Newer cruise controls will adaptively adjust speed to prevent you from
creeping up the backside of the vehicle in front of you.

>
<...>
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Many adaptive cruise control systems (but not all!) have full authority down to zero-speed; they control the brakes as well as the throttle.

>
This ---------^^^^^^^^^^^^^^^^^^^^^^^ is the difference between them and legacy
"cruise control" systems.  It can only control the vehicle's speed to the same
degree that a human can /with just the throttle/.
>
In The West, it is not uncommon to find yourself driving through varying
elevations (mountains).  Relying solely on the engine for braking often
won't allow you to comply with the posted speed limits *or* "safe driving
conditions".
>
[OTOH, being overly reliant on the brake can lead to brake overheating and
failure]

 My recent cars automatically increase engine RPM by changing gear to maximize engine braking, in addition to using brakes if necessary.
 Some people find that disturbing to have the engine spinning at 4000-5000RPM down steep hills.

This is how we drive "manually" (manually forcing the automatic into a lower
gear).  But, it is distressing to have the car operating like this for a 20
mile stretch!