...@googlemail.com> gurgled happily, sounding much like they were saying: Far be it for me to interfere on a post that is addressed to Duhng, but I'm not sure that you're correct that a car may not be driven if it does not have a current/valid VED. It can be - in certain very limited circumstances. They being? To or from a pre-booked MOT, on tradeplates, ...

... interfere on a post that is addressed to Duhng, but I'm not sure that you're correct that a car may not be driven if it does not have a current/valid VED. It can be - in certain very ... driver/owner of the vehicle may be prosecuted (by the DVLA, not the police) for the offence, but the car may not be siezed at it would be if it was uninsured Oh, yes, it can... On ...

...to interfere on a post that is addressed to Duhng, but I'm not sure that you're correct that a car may not be driven if it does not have a current/valid VED. It can be - in certain ...the driver/owner of the vehicle may be prosecuted (by the DVLA, not the police) for the offence, but the car may not be siezed at it would be if it was uninsured Oh, yes, it can... On what...

...me to interfere on a post that is addressed to Duhng, but I'm not sure that you're correct that a car may not be driven if it does not have a current/valid VED. It can be - in certain very limited ..., the driver/owner of the vehicle may be prosecuted (by the DVLA, not the police) for the offence, but the car may not be siezed at it would be if it was uninsured Oh, yes, it can...

...>Good point. Let's look at the error. On a 1:3 hill (probably the steepest to be encountered), the angle will be arctan(1/3) = 18 degrees. For a hypotenuse of 1 unit (the true distance that the car travels), the horizontal distance that the GPS senses will be cos(18 degrees) = 0.95 So the GPS will read 95%% of the true speed and the error will be (1-0.95)/1 = 5%%. I suppose a...

...Good point. Let's look at the error. On a 1:3 hill (probably the steepest to be encountered), the angle will be arctan(1/3) = 18 degrees. For a hypotenuse of 1 unit (the true distance that the car travels), the horizontal distance that the GPS senses will be cos(18 degrees) = 0.95 So the GPS will read 95%% of the true speed and the error will be (1-0.95)/1 = 5%%. I suppose a really ...

...GPS + the current speed sensor for when there's no satellite coverage (such as inside tunnels) would be enough. The speed sensor could be calibrated from the GPS when there is a signal. This is already used for some upmarket in-car GPS navigation systems. GPS doesn't give an accurate speed on gradiants. If you're the amazing engineer you make out you'll know why won't you. B2003

...... On Mon, 15 Sep 2008 05:29:39 -0700 (PDT), Boltar <boltar2003@yahoo.co.uk> wrote: I suppose one reason is that the radius, or rather, the circumference of the wheels of cars/lorries etc aren't constant. It will change as the tyre wears down and as the pressure of the air inside it expands/contracts/leaks. Perhaps a different means of measuring the speed of a ...

... in east London when a car mounted the kerb and hit his... mention those cases. Yes but cars are much more damaging and ... 'trying to avoid having her car towed'...' "...The woman driver was ....worldcarfree.net/ Help for your car-addicted friends in the U....'t have been driving the car even if clean and sober....>Point two: Driving an untaxed car. Yep, thats not allowed either....

...and train speedos can be accurate why can't they do the same for cars? It can't be hard in these days of electronic everything to have... correct pressure so they're not the culprit. So why don't car manufacturers bother? I suppose one reason is that the radius, or rather, the circumference of the wheels of cars/lorries etc aren't constant. It will change as the tyre wears ...