Test Marathon: New Generation Opel Astra Enters Finishing Straight

• Arctic Circle: Testing dynamics and warm-up behaviour at -30^oC in Swedish Lapland
• Dudenhofen Test Centre: Chassis development for safety and comfort in Germany
• EMC lab in Rüsselsheim: Resistance to electro-magnetic waves

Development of the all-new Opel Astra is fully on target, the premiere of the 11^th generation of the brand’s best-selling compact model is now just weeks away. Initially created – like all modern automobiles – with the assistance of computer-aided design, since last winter the new model has been undergoing final testing, fine tuning and validation in real life conditions. Now the Astra is entering the finishing straight of a true test marathon.

Opel engineers took prototypes and development vehicles far north to test the new model on the icy roads and in the deep frozen air of Swedish Lapland. Closer to home, they have been pounding around the test tracks at the Dudenhofen Test Centre and most recently, carrying out validation drives on public roads in the Rhine-Main region, accompanied by senior management. At the same time, the all-new Astra was taking its final tests in the Rüsselsheim EMC laboratory (Electro-Magnetic Compatibility) before receiving type approval for commercialisation.

“The demanding test programme of the all-new Astra is going exceptionally well”, says Astra Chief Engineer, Mariella Vogler. “The development team – which, by the way, comprises more female engineers than ever before – has created an uncompromisingly cool new generation of Astra that will thrill our customers.”

With the new Astra, Opel is demonstrating German precision in every detail and taking direct aim at the sweet spot of the compact market sector. The pure and bold design, top technologies and exciting powertrain line-up – including plug-in hybrid electric drive – will make it a benchmark in its class.

Winter testing: High comfort and safety under all conditions

Winter 2020/2021 in Sweden. As usual at this time of year, Lapland is a frequent travel destination for Opel engineers. On this occasion, they brought the next generation Astra with them. At temperatures as low as -30^oC, chassis experts turned lap after lap on the slippery surfaces of the specially prepared tracks, continuously optimising the electronically controlled systems for stability, traction and anti-lock braking. The objective: the new Astra must always handle safely and consistently, regardless of the surface – be it ice, snow, slush or wet or dry asphalt. Or in other words, it has to behave like an Opel – under all conditions.

“During development we made sure that the new generation Astra will once again offer drivers and passengers a lot of driving fun and comfort”, says Opel’s head of vehicle dynamics, Andreas Holl. “On the one hand, our sophisticated and dynamic design ensures that occupants will always feel safe, even at high speeds on the motorway. On the other, it offers plenty of comfort – even on poor road surfaces – for a relaxed driving experience.”

During their stay in Lapland this year, Opel’s chassis specialists were joined by their colleagues from “HVAC” (heating, ventilation and air conditioning). One of HVAC’s goals is to make sure that the passenger compartment warms up quickly. So they monitored the new Astra’s engine heat rejection, coolant flow, heater core performance and blower airflow, as well as the heated steering wheel and the heating of the front and rear seats.

But warm-up testing is not only done so that customers feel warm and comfy on cold winter mornings. Warm-up performance is also precisely defined by regulation and even more stringent in-house safety standards, which state that the frozen windshield and side windows of an Opel must be clear of ice and fog in the shortest time to ensure safe driver visibility.

Furthermore, as the next generation Astra as plug-in hybrid will play an important role in continuing the electrification of Opel’s product portfolio, the engineers also kept a close watch on the warm-up times of the lithium-ion battery, to make sure that the performance of the cells meets the standards for electric driving experience even in cold weather.

Dudenhofen Test Centre: Torture, on and off the test tracks

Performance of a different kind is evaluated at the Dudenhofen Test Centre in Germany. Engineers from the competence centre for “ADAS” (Automated Driver Assistance Systems) in Rüsselsheim used the proving ground’s high speed oval and long straight to calibrate the new Astra’s advanced technologies – from Adaptive Cruise Control and Emergency Braking, to Forward Collision Alert and Rear Cross Traffic Assist.

The pre-production cars used for these tests also had to meet high standards on Dudenhofen’s long straight. Here, like every Opel, the next generation Astra had to demonstrate it is “Autobahn-proofness”, meaning that it must remain controllable at speeds well above 140 km/h and stable under hard braking. While driving at high speeds on the oval, the Opel engineers also took the opportunity to evaluate components such as the bonnet and windscreen wipers. Nothing is allowed to flutter, vibrate or cause irritating noises.

After working up a sweat in the high-speed driving tests, the new Astra cooled down in the drive-through water trough, at various depths of a minimum 25 centimetres. Despite pushing a big wave of water in front of itself, the test car is not allowed to “inhale” or “swallow” any water – the powertrain, the electrical system and every part under the bonnet must stay protected from water.

There was no respite for the new Astra even after it left the test tracks. Despite the tortures meted out on the high-speed oval, the handling circuit or in the water trough, the Opel engineers also took the test vehicles into the Dudenhofen climatic chamber. This environmental test facility is for evaluating the operability of vehicles, subsystems and components in extreme conditions. For the next generation Astra, the climatic chamber was set up to test the car’s sealing against dust and sand.

In addition to the climatic chamber, Opel put test cars into a climatic wind tunnel to validate the new Astra’s performance under a variety of operating conditions. For example, the climatic wind tunnel simulated driving in traffic jams, uphill and down, in order to test the cooling of the brakes. The engineers were even able to find out if swirling snow in front of the vehicle could block the air intakes.

On the boss’s agenda: Validation drives around Opel’s hometown

Climatic conditions conducive to dust, sand or snow were not expected during the current phase of testing. Validation drives take place with prototypes and engineering cars at several stages throughout the development of a new model. They are for verifying systems and subsystems and validating their overall integration in the vehicle. As development approaches the final stages, the cross-functional team of engineers and technicians is joined by members of senior management, including the boss himself – Opel CEO, Michael Lohscheller.

The most recent validation drives of the still-camouflaged new Astra took place in June on public roads in the Rhine-Main region around Opel’s hometown – and the car’s “homeplant” – of Rüsselsheim. The engineers and managers were occasionally joined by journalists from the press.

Electro-magnetic immunity: Prerequisite for type approval

While development prototypes and pre-production vehicles are driving in the far north, in Dudenhofen and on public road in and outside Germany, others also undergo intensive testing on test rigs and in laboratories in Rüsselsheim. Electro-magnetic compatibility (EMC), for example, is tested throughout development. Furthermore, no car can be sold in Europe without passing EMC tests during the type approval process. EMC testing ensures that a car’s electronic systems do not suffer from interference.

The Opel team tested the new Astra’s immunity to electro-magnetic emissions in the purpose-built EMC lab in Rüsselsheim. While the test car is exposed to emissions radiated across a wide range of frequencies, special absorbers on the walls “soak up” the transmitted emissions so that they do not reflect back into the chamber. The engineers thus obtain clean, reliable data. The new model only gets the “green light” – and finally receives type approval – when all its systems have demonstrated their immunity to electro-magnetic emissions.