Renault Trucks reports that it has conducted the most stringent testing programme in its history on the open road and at its La Valbonne test centre site in France, on its

new Euro 6 truck range, which will be first delivered to customers at the end of September/early October.

The testing programme used the most highly sophisticated computer-assisted design and development tools, says the company.

The tools Renault Trucks now has at its disposal enable it to develop both the vehicle’s interior and exterior. Using a special helmet and gloves, the virtual reality platform simulates visibility, taking into account driver size and corpulence, as well as the ergonomics of the controls.

It also assesses the quality of driving and resting comfort drivers experience by analysing life on board. “Right from the beginning of the project, well before completion of the first prototype, the virtual reality platform enables us to define the forms and layout of the controls on the dashboard together with the storage spaces, but also the size of the windscreen and the position- ing of the rearview mirrors,” explains Renault renewing of long distance and construction ranges VP Thierry Hours.

All the information gathered with the use of simulation and the first test drives is used by the Renault Trucks design office. It is also valuable for its suppliers as well as for staff at the production plants, who use the information to develop the manufacturing processes, which will ensure the products’ high quality, as well as vehicle maintenance procedures for the Renault Trucks network.

Stereolithography

To develop the cab interiors for its new range, Renault Trucks employed the technique known as stereolithography, also used in Formula 1.

This technology, based on a principle similar to that of three-dimensional printing, uses computer files to produce prototype parts in a few hours and without any manufacturing tooling. The part is formed in a resin bath by solidification, using a laser and, upon completion, is totally fault free. “This technology brought us a great deal of flexibility and reliability,” explains Hours.

Electromagnetic-chamber Testing

Electromagnetic fields are encountered just about everywhere on the roads, such as at toll booths and under high-voltage cables. To make sure that the vehicle’s on-board electronics can operate with total reliability, Renault Trucks has developed a comprehensive testing procedure. In particular, this features an electromagnetic chamber, which checks vehicles’ electromagnetic compatibility and ensures their immunity. All vehicles in the new Renault Trucks range have been tested in this facility.

Road and Bench Test Trials

“In 20 weeks the vehicles undergo the equivalent of a year’s actual use,” says Hours. Some of the trials take place at 90 km/h on a speed circuit, while others are on tracks that simulate extreme conditions by deliber- ately deforming the cab or vehicle body significantly, so that the vehicle can be tested to the extreme under all conditions.

If a part breaks, it is analysed, immediately modified and then the engineers test it again to ensure optimum quality for the final end product.

The purpose of the reliability tests is to subject every part of the vehicle to the customers’ typical patterns of use. Body, cab, and pneumatic and electric circuits are all tried and tested with respect to torsion and vibration on the test benches.

The engines accumulate endurance hours on the test benches in every possible on-the-road situation.

Tests that subject the doors and grille to misuse when being opened and closed are also done.

All the electronic components are put under strain on a specially designed bench that contains all the electronic functions inside the truck as well as those in the body and the engine.

Constant improvements are also made to the cab, which is tested on specially designed test benches as well. A cylinder system puts it into a series of extreme situations that test its solidity, shock absorption capacity, behaviour on the road and under difficult conditions, and its longevity.

In addition, for these vehicles, Renault Trucks also conducted tests in a life-size wind tunnel, which helps engineers improve the trucks’ aerodynamics and rework some parts to better the fluidity of airflows, thereby reducing fuel consumption.

These test bench trials amount to the equivalent of over five-million hours of tests on all the vehicle components: body, cab, engine, gear-box and electronic components.

All functions are tested and the operations are repeated thousands of times, for absolute certainty that every component works properly and is totally reliable.

Simultaneously, the new trucks are driven on the open road, so that they can be tested under real-life conditions with respect to features like fuel consumption, road holding, noise and vibration levels, and life on board during the daytime and at night.

A total of 32 different features are measured to ensure product quality, performance and reliability, says Renault.

Renault Trucks also carried out several series of tests under extreme conditions, and at high and low temperatures. The extreme cold trials took place during three winters in Lapland, Finland, where temperatures regularly fall to –40 °C. The extreme heat trials were conducted during three summers in southern Spain or Oman, where temperatures regularly reach 45 °C and can hit 60 °C in the sun.

“During these trials, every aspect of the truck is tested – road handling, of course, how well it starts after a really cold night, how it performs on seriously snow-covered roads or in thick dust, and life on board, too.”

“Our testers live and sleep in the vehicles, checking that the cab is sufficiently insulated, that the air-conditioning works properly, the heating, the demister, on-board accessibility, even whether they can open the tool box when it’s extremely cold. The idea is to find themselves confronted with all the different kinds of situations our customers might have to deal with,” explains Hours.

Renault Trucks has an engine development and testing facility employing 1 000 people in Lyon, France. It incorporates the means of testing the performance, endurance and consumption of the new range’s drivelines.