Path: ...!feeds.phibee-telecom.net!2.eu.feeder.erje.net!feeder.erje.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail
From: Don Y <blockedofcourse@foo.invalid>
Newsgroups: sci.electronics.design
Subject: Re: Speed limiters
Date: Sun, 7 Jul 2024 16:58:24 -0700
Organization: A noiseless patient Spider
Lines: 42
Message-ID: <v6fa32$hoa9$3@dont-email.me>
References: <v69vj4$3fu0d$1@dont-email.me>
 <tq0i8j9dsqov0mr4u622979s750oeqg3vd@4ax.com> <v6bt5c$3sp48$2@dont-email.me>
 <psok8j1sbnslu0p1b13q0o67eue2u7poqo@4ax.com> <v6ee28$cpga$2@dont-email.me>
 <v6eeil$d5u9$1@dont-email.me> <v6ehef$dmn2$1@dont-email.me>
 <v6f666$h5r6$1@dont-email.me>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
Injection-Date: Mon, 08 Jul 2024 01:58:27 +0200 (CEST)
Injection-Info: dont-email.me; posting-host="1204b6b780de24b9cb690be0c57d3575";
	logging-data="581961"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX1948Julck4uMgOUX118vDIb"
User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:102.0) Gecko/20100101
 Thunderbird/102.2.2
Cancel-Lock: sha1:IOva/mZbJVvKHdglz2NSS7W60Wc=
In-Reply-To: <v6f666$h5r6$1@dont-email.me>
Content-Language: en-US
Bytes: 3098

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.
>>>
>>> <...>
>>>
>>> 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!