Carrera GT

Geek speek: "full scale deflection" (an analog gauge which has the indicator needle against the "pin" that prevents the needle from rotating off the dial scale)

AllanJ

Gotchya. As you can tell, I haven't gotten around to installing it yet.

Carrera GT

Nice comparison software for the VBOX-- being able to see the vehicle position on the line (not just the distance point around the track) is pretty compelling. I wonder what kind of GPS sampling resolution they achieve to be able to position the car location within 10cm or whatever -- I see they advertise a 100Hz unit (at $6K+) but I wonder if there's a differential beacon or something to improve the fix?

BnS Racing

Yes, the videos are very basic. Just meant to get you going. As far as I know, there is no way to change the range on the accelerometer displays ( the graphics cross, like a friction circle, as opposed to the graph). One thing you might try is to zero the accelerometers. The accelerometers are zeroed when they leave the plant. If you mount the systems unit in the car, at a place that is not level (let's say it's tilted forwards, just a little) then the accelerometer will be off, and the unit will think that you are braking, even when the car is at rest. If you navigate on the website to 'Support', 'Discussion Forums', 'Support' you can see additional information, including a utility to run on the box once it is installed in your car, that zeros the accelerometers to the particular orientation in your car. Be sure that the car is perfectly level before doing this.

About exporting the raw data, I have requested this some time ago (look in the Wish List section of the discussion forums.

BnS Racing

There is actually a detailed description of focusing the cameras on the website. Navigate to the 'Support' page, then 'Discussion forums' and then the 'Race-Keeper Discussion' forum. There is a description of how to focus the cameras. I like using a cheap DVD player that has a 'video in' port so I can actually see what the cameras are seeing, real time. Switch the system to single stream and connect the camera that you are focusing to video port #1. If you have a good 12v power supply outside of the car, you can even do this indoors.

AllanJ

...it would be nice if the default range was +/-1.5g instead of the tiny range they have now, if they can't get to a GUI mod any time soon. 1.5g will cover most sports cars (although a local A-MOD autox car can do 3g in the corners!)

Cheers,

BnS Racing

Check out their manual. The resolution is 10cm, however their 'absolute positioning' accuracy is +-5m 95% of the time. Also, you have to download a map of the track that they provide to show the path of a car around a circuit. If they don't have a track map for the track you are at, you will have to create one using the procedure they describe which involves driving around the course with the antena mounted in a specific place on your car, and driving around once on the left side and once on the right side, again subject to the +-5m accuracy.

I am not saying that this in not useful, or cool. It all depends on how much time and money you are willing to put into data/video acquisition systems.

If you need to increase accuracy, you can get a DPGS unit that transmitts correction data to the GPS receiver.

The sampling rate 10Hz or 100hz just defines how much data you are collecting. A higher sampling rate will generate a lot more data in the same amount of time.



It's like the units that advertise that they have two GPS receivers and can plot the angle that the car is moving. But very simply, if you have two receiving antena's 3 meters apart with a 5 meter accuracy, they could tell you that the back of the car was in front of the front of the car (hopefully this is not the case!!!!! cause then you would be traveling backwards). This may be very simplistic, so correct me if I am wrong.

BnS Racing

I'll check and see what the deflection scale is for the acceleromter graphics (not the graphs).

Bill Verburg

Where can we obtain a list of the tracks for which there are maps?

alternately is there a map for Lime rock, Watkins Glen(long), Monticello(full)?

BnS Racing

Bill: Sorry, I thought I responded to you, but I may not have hit the send key.

Their website is www.racelogic.co.uk or their US outlet - www.vboxusa.com. Although I could not see anything about downloading track maps from their site.

Carrera GT

billstevens61 -- Karma win to you. You've got the second most laid back sales operation on the planet.

Bill Verburg

Ok, they appear to have LimeRock but not the others

BnS Racing

I found a way to determine what full deflection is on the accelerometers. If you look at the accelerometers in video mode, and advance frame by frame, you will notice that the accelerometers go from a dot to a dot with a circle around it at full deflection. Advance the video to the point where the dot appears and switch to the standard or graph display (press either 'x' or 'g'), and the value for the accelerometer will be displayed on the right side of the window.

When I checked, it looked life full deflection was about .9 g's.

AllanJ

That's way too low. Not sure how the programmers came up with that number unless they tested it on a Toyota Tercel and assumed sports cars would be a little higher.

Like I said earlier, if they can set the default to be 1.5g for now and add a GUI update later on so the user can change it, it would make the accelerometer useful. Right now there is no point in using it when it'll max out so easily.

Cheers,

BnS Racing

Allan: Please go to the Race-Keeper website, click 'Support' then 'Discussion Forums' and 'Wish List'. I have submitted your suggestion. Check here for an resonse.

BTW, there are only two months more to register for their New Year's Eve giveaway - a SE system. This is open to everyone! Even if you have already purchased a system! Present users will have their choice of a second system, or a refund of the system price.