You either have it or you don’t. ESP – electronic stability program – is probably one of the most important safety features to arrive on the van scene since the introduction of seatbelts. And it’s a device which is closely allied to the other two examples in the first paragraph.
The new Ford Transit, which was launched late last year, has ESP as a standard fitment. The Mercedes-Benz Sprinter has it too and so does the Volkswagen Crafter.
All the other 2.8-3.5-tonne gvw vans on sale in the UK today either offer it as a paid-for option or don’t have it at all.
Thus, as the panel van sector fragments further and further, we see yet another hierarchy forming – safe and not quite so safe.
Until you’ve actually driven a van with and without ESP on a test track and compared the differences, it’s difficult to understand exactly how important this device is.
So Ford invited a party of journalists to sample its wonderful new technology at the ProDrive track in Warwickshire – and all those present were soon persuaded that any fleet managers NOT specifying ESP on new vans were indeed shirking their corporate responsibilities in the safety arena.
For those who don’t know what ESP is, let’s go right back to basics...
Electronic stability programs are also known as anti-skid control and work automatically to correct sideways movement in a vehicle. Adaptive ESP, the latest step forward, automatically adjusts itself depending on where loads are placed.
The good thing about such systems is that drivers don’t need any lessons in how to use them. Most of the ESP systems on today’s vans are made by Bosch.
During our Ford test day we were able to try out the vans with and without ESP and the safety possibilities soon made themselves obvious. ESP won’t save you if you lose it big time, but for most everyday examples of bad driving – especially in the wet – ESP will simply wink its little orange light on the dashboard and correct the vehicle often without the driver feeling a thing.
The only danger, of course, is that once drivers know they have an ESP system on board, they may just be tempted to push their luck that little bit further on the roads.
But that’s a risk management issue and is no reason not to fit ESP as standard.
How ESP works
In a van, the centre of gravity shifts depending on where loads are placed and consequently the risk of roll-over may increase.
Bosch has developed a system specifically for light commercial vehicles that automatically adapts its control mechanisms to the current situation.
Bosch groups the algorithms that detect load under the designation ‘Load Adaptive Control’ (LAC).
This function determines the longitudinal position of the vehicle’s centre of gravity and its actual weight by evaluating its behaviour when accelerating and braking.
In addition, the LAC determines the vehicle’s ‘characteristic speed’. This value depends strongly on the total weight of the vehicle and describes how the vehicle reacts to steering operations.
In vans, the control provided by ESP when supplemented by LAC is now even more comfortable and keeps the van more reliably on course in critical situations – and the danger of rolling over is also significantly reduced.
The safety of vans on the road can be improved even further by other additional ESP functions: for example, the risk of roll-over drops further if critical lateral acceleration forces can be detected as soon as they arise, and a stabilising intervention is initiated.
ESP controls vehicle dynamics by selectively braking individual wheels and reducing engine torque. Within the limits set by physical laws, this markedly increases driving safety. As a side effect, because ESP distributes the braking force across the axles in accordance with the current load, the wear on both brakes and tires is reduced, leading to lower maintenance costs.