The Cyber-Spy.Com Usenet Archive Feeds Directly
From The Open And Publicly Available Newsgroup
This Group And Thousands Of Others Are Available
On Most IS NNTP News Servers On Port 119.
Cyber-Spy.Com Is NOT Responsible For Any Topic,
Opinions Or Content Posted To This Or Any Other
Newsgroup. This Web Archive Of The Newsgroup And
Posts Are For Informational Purposes Only.
From: email@example.com (Mike Harding)
Subject: Re: Car speed conversion error
Date: Tue, 19 Nov 2002 22:03:32 GMT
NNTP-Posting-Date: Tue, 19 Nov 2002 21:59:12 +0000 (UTC)
X-Newsreader: Forte Free Agent 1.1/32.230
On 19 Nov 2002 16:31:12 -0500, firstname.lastname@example.org
(Stephen H. Westin) wrote:
>email@example.com (Amy) writes:
>> Does anyone know what is the conversion error when an analog pulse
>> waveform from vehicle speed sensor gets converted to digital format
>> which can be processed by electronic control unit in a car? Is there
>> any standard on the tolerance for this conversion, or is it up to car
I think that analogue pulse is usually a digital one. The error
through the electronics would be next to stuff all - probably just
the tolerance of the crystal oscillator used by the micro which
measures the pulse interval. Tyre wear would probably account
for a much larger error.
>I don't think there is any standard for speedometer accuracy, so the
>market rules. Italian cars used to be famous for speedos that would
>read 10%-15% high.
There sure is in Australia. Australian Design Rules (and I
think the UK does too) require speedos to be within +/- 10%.
Which makes our tolerance of +3kph on a 100kph speed
limit before a ticket is issued an extreme example of
Go Back To The Cyber-Spy.Com
Usenet Web Archive Index Of
The sci.electronics.design Newsgroup