The VBOX is a powerful instrument used for measuring the speed and position of a moving vehicle. It is based on a new generation of high performance satellite receivers, and will measure acceleration, braking distances, lap times, cornering forces and much more.


Due to the small size and simple installation procedure, the VBOX is ideally suited for use in cars, bikes, off-road vehicles and boats.

About GPS

The Global Positioning System is a satellite based navigation system made up of a network of 24 satellites placed in orbit by the U.S. Department of Defence. GPS works in any weather conditions, anywhere in the world, 24 hours a day. There are no subscription fees or setup charges to use GPS.

Each GPS satellite has an on-board atomic clock, and by receiving signals from at least three satellites, the receiver can tell the distance from itself to each one. By triangulation, the position of the receiver is then calculated. The length of time it takes the signal to travel from each satellite to the receiver is slightly affected by the conditions in the outer atmosphere, and this affects the precision which can be achieved without any additional corrections.

If you try to measure velocity using the change in GPS position over time, then the result is too noisy to be used for any vehicle testing.

However, when the receiver moves in relation to the satellites, the movement causes a shift in the signals, (the Doppler effect), and these small changes can be measured, and used to calculate Velocity.

Applying this technology to vehicles can provide useful measurements about the behaviour of a vehicle during testing, and have a number of advantages over existing sensors. They are compact, very quick to fit, accurate, and they work in any weather.

About VBOX

The VBOX is based on a survey grade GPS engine with gives an extremely accurate velocity measurement (see about GPS). Since the launch over 1200 systems have been sold to vehicle manufacturer's, tyre companies, magazines and race teams all over the world, making the VBOX the highest selling GPS based test equipment available today. The VBOX sets new standards of accuracy with a velocity accuracy of 0.1kmh, and a braking distance accuracy of less than 5cm. That is why it is the number one choice for speed measurement systems in the world.

It has the most comprehensive and easy to use software available for speed measurement equipment, developed by a team of in-house engineers over the last four years. With this software you quickly and easily measure Accleration, Braking distances, Laptimes, Peak and average g-force, Circuit Position, Coastdown tests and many more.

The VBOX can be used to measure a number of different parameters of a vehicle's performance, both straight line acceleration / braking and cornering. Complicated tests can be set up in a number of minutes, using comprehensive templates, and to trigger at a certain point on a test track, you can define a "virtual" gate which is referenced using the GPS.

Frequently Asked Questions

How long does it take to lock onto the satellites?
The satellites are acquired between a minimum of 10 seconds and a maximum of 2 minutes from power up.

How does the VBOX measure lateral acceleration without an accelerometer?
The lateral acceleration is calculated using the velocity and heading information. From this it calculates the radius of turn, and then uses the formula latacc = V (squared) / Radius.

Can I use the system on a motorbike, and where do I put the antenna?
Yes, the VBOX system is small enough to be carried on a person, so motorbike testing is easily achievable. You must put the antenna on the top of the helmet to get the best satellite reception.

Can I put tape over the antenna to hold it in place?
Yes, if the surface is non ferrous (eg aluminium, fibreglass etc), then a strip of tape over the top will hold it in place, and will not affect the signal.

How does the VBOX still work whilst going under a bridge?
When a vehicle passes beneath a bridge, the bridge wipes across the antenna's view of the sky over short period of time. This means lock is broken and then re-made on each satellite in view.

We have spent considerable time optimising the settings and firmware on the GPS engine we use to regain lock on a satellite instantly it comes back into view, (as long as other satellites are in lock). Therefore, as you pass under the bridge, you lose around 1 or two satellites out of the total, but at all times there still should be enough in view to continue calculating velocity and position.

We do not use "off the shelf" GPS engines to achieve this high performance re-acquisition, and if your test track has a bridge, then this is an essential feature to prevent loss of data.

How sensitive is the system?
If you move the VBOX aerial with your hand, the speed with which you move the aerial is displayed instantly on a laptop screen, the response is instantaneous, and sensitive right down to 0.1 kmh.

Does it require a laptop computer?
The VBOX stores data on a compact flash card, which means you can log for anywhere from 4 hours to 400 hours depending on the size of the card.

After the test is completed, a laptop is required to download the data and analyse the results. Alternatively, the laptop can be connected at all times during the test, and then the results can be monitored in real time.

There is also the option of a digital display which can be mounted on the dashboard or windscreen and will show vehicle Speed, Distance or Time.

What else can be connected to the VBOX?
A brake trigger can be used to signal when the brake pedal was pressed for use in certain brake distance calculations and there is a switch to start/stop logging. There is a choice of a digital or analogue output to allow the VBOX to be connected to a separate data-logger, and information is also transmitted over RS232 and CAN.

A number of different modules can be connected via CAN to measure various analogue and digital inputs. As these modules are linked via CAN, they can be distributed around the test vehicle, minimising the sensor connection distance.

Without a shadow of a doubt, GPS is set to become the new reference by which the performance parameters of a vehicle are determined. All other forms of speed measurement are superseded by this technology in ease of use, and by obviating the need for calibration.

The VBOX encompasses this new technology, and exploits all of the available features in an easy to use, and powerful package.