Back in June I showed you a video of a Saab 9-5 driven by robotic controls, programmed according to GPS data and used for closed loop testing.
Here’s a quick recap:
A lot of vehicle testing takes place where the car is driven around a circuit by real people. There are times when this is absolutely necessary. People with experience in such things need to ‘feel’ the car as it develops. In some instances, however, the testing process can be hampered by human error because humans are ‘variable’. That is, they won’t necessarily repeat the exact same action time after time after time.
If we can develop a machine to do some of these tests, you get the same circuit driven the same way every time and the vehicle data retrieved from such a test should be based on consistent inputs in every respect. More than that, steering robots are actually able to give more precise and more dramatic (i.e. faster) steering inputs that humans can, and they don’t get tired either.
The simple version of “How” involves a track modelled on GPS data and some sophisticated hardware being installed into the car to steer it according to this pre-programmed course. The hardware used to control the steering is a steering robot from Vehico and the work is done in cooperation with them. The steering robot is currently only able to perform so-called ‘open loop’ tests (steering as function of time) such as step-steer, sine-sweep steer, and sine-with-dwell steering, which are used for vehicle dynamics characterisation. The task for Klas and Carl, which even the experts say is very challenging one, was to create the control software necessary to control the steering such that the vehicle follows a pre-defined path using advanced GPS and motion sensors as input data.
The guys responsible for this job were Klas and Carl, two students from Chalmers University who completed this project in conjunction with Saab as their Masters thesis.
Their thesis presentation was made back in June and I’ve just been forwarded a copy of the video they made as part of that presentation. In the video, you can see the robotic steering system in action, a vehicle’s eye view of the road they’re driving as well as speed and tracking information.
It’s all fascinating stuff and indicative of just some of the technical work that goes on behind the scenes here at Saab.