Speed Accuracy

Captain Kirk · 24 May 2006 at 14:20

I was having a "debate" with a friend the other night (whilst drunk) on speedo accuracy. I said it was crap, due to so many different factors (i.e. tread depth, tyre pressure, sensor accuracy etc) and that TOMTOM on my pda was a lot more accurate due to the gps. Could someone settle this argument or add any other comments on which one is more accurate. Cheers

Acolyte · 24 May 2006 at 14:21

GPS is far more accurate compared to your speedo.

Glaucus · 24 May 2006 at 14:23

Acolyte said:
GPS is far more accurate compared to your speedo.

debate closed.

MrMatteh · 24 May 2006 at 14:25

how could tomtom be *less* accurate is what you need to ask your mate

Psycrow · 24 May 2006 at 14:47

GPS is accurate to something like 0.1m/s with a 3 or more satellite lock. Your speedo can be up to 10% out due to the many many little errors that mount up as you go through the system.

Nozzer · 24 May 2006 at 14:49

Psycrow said:
GPS is accurate to something like 0.1m/s with a 3 or more satellite lock.

Unless you're going up/down hill. But it's still more accurate at a cruise.

NathanE · 24 May 2006 at 15:02

Nozzer said:
Unless you're going up/down hill. But it's still more accurate at a cruise.

How comes? GPS can determine altitude too ya' know?

Nozzer · 24 May 2006 at 15:03

Simple trigonometry, my dear boy.

Captain Kirk · 24 May 2006 at 19:02

Thank you, I knew I was right. I don't like being wrong, and I'm not very often

The_Dark_Side · 24 May 2006 at 20:01

Captain Kirk said:
Thank you, I knew I was right. I don't like being wrong, and I'm not very often

so when you're at warp 9 does you're speedo read slow or fast?

PMKeates · 24 May 2006 at 20:02

Mine just says 120mph, so definitely slow :confused:

Captain Kirk · 24 May 2006 at 20:12

At about 70, it reads around 65, so need to do about 75 according to speedo to be doing a real 70. In theory

Dr Who · 24 May 2006 at 20:28

Speedo accuracy varies at the speed you are travelling at...

My accord was about 5mph over at 50 mph, at 100mph it was 1mph different to the tom tom gps!!!

:eek:

daz · 24 May 2006 at 20:55

Captain Kirk said:
At about 70, it reads around 65, so need to do about 75 according to speedo to be doing a real 70. In theory

I think you mean at 65, it reads 70. T'other way around.

Lashout_UK · 24 May 2006 at 20:59

Speedo in the 1850 was spot on.

Speedo in the 1500....doesn't work, Officer