Roush simulator puts AVs through fast paces

You can't bring autonomous vehicles to market without ensuring they are safe, but as the technology gets more complicated, safety testing and validation has proved to be challenging.

Autonomous vehicles are only as reliable as the test that validates them. Modern vehicle technology is pushing durability requirements higher, and that's created a need to go beyond the kind of trial-and-error testing that traditionally takes place on a proving ground.

Gerald Roesser, manager of a new test lab for Roush, an engineering, testing and prototyping company in suburban Detroit, says watching a test driver repeatedly drive around a track, stopping for maintenance fixes and waiting for bad weather to pass is too time-consuming.

Also, there are too many test driver bathroom breaks.

Enter the road-test simulator. Facilities such as the new $6 million Roush Advanced Durability Lab in Livonia, Mich., are giving civilian and military customers an alternative way to test the long-term durability of AVs.

Take sensors. Making sure the sensors on connected and autonomous vehicles are positioned accurately is important for passenger safety. This is one area where simulators can help.

"We can take the vehicle off the road and use this rig to put inputs into the vehicle to understand the positional requirements for the sensors," said Jeff Johnston, president of Roush Testing Services, referring to the flexible test rig, which is one part of the simulator.

"As a vehicle is going down the road, it's bending and twisting on the road inputs —like cobblestone or potholes — therefore, the sensors need to be positionally accurate to each other so that the algorithms knows exactly where the vehicle is in space. This is often done on a proving ground by trial and error, which can take many miles to figure out.

"Here, we can do it in a controlled setting," he said. "Algorithm engineers can come and evaluate whether they need tighter or more relaxed tolerances, for example."

Roush's test lab has the capacity to gauge vehicle durability at subsystem, component and full-vehicle levels.

The lab includes 3,000 square feet of bedplate for the vehicle; subsystem and component durability testing; private, isolated control rooms; a central, 450 gallons-per-minute hydraulic pump; and a cooling tower.

Johnston says the full-vehicle test produces accurate loads in the vehicle suspension and allows simulation of maneuvering events — for example, braking and cornering — along with rough-road simulation.

Roush uses a six-degrees-of-freedom test rig that can shorten vehicle durability assessments from months to weeks, he said.

Automotive and military clients have the option of running flexible test-rig configurations 24/7.

Roush engineers say 1 mile on a proving ground is equivalent to about 20 real-world miles.

They say that ratio can be compressed further at their lab, for faster testing of how long a vehicle can last.

"At the end of it, we can complete a vehicle life in about two to three weeks," said Roesser. "That's one vehicle per month, which is a lot faster than a proving ground test."

Military clients can also minimize the risk of exposing confidential projects by working in the lab's controlled environment.

Moving forward, Roush is looking to make a process where a vehicle isn't needed at all. "We're working on a process where we can enable design-load collection very early on without having a vehicle because there's a trend for fewer prototypes in the military and automotive industries," Johnston said.

"With the collection of some parts, we can get loads for the entire vehicle to help designers and engineers get the design correct the first time. Then, we evaluate the vehicle at the end, and everybody is happy."