Path Following
The AB Dynamics path-following system uses a steering robot and real-time feedback from a GPS-corrected motion pack to guide a vehicle along a specified path. The system is capable of accurately controlling the vehicle at high speeds and high levels of lateral acceleration, so that handling manoeuvres can be performed with outstanding repeatability.
Indoor path-following
Path-following can now be done indoors with no GPS signal, proven in this video showing a demonstration of indoor path-following at IIHS Vehicle Research Center in the USA. A vehicle fitted with AB Dynamics’ driving robots, an OxTS motion pack and the Locata indoor positioning system performed path-following which was indistinguishable from normal operation under open skies with GPS which demonstrates that AB Dynamics’ robots can be used for high-precision driving both indoors and outdoors.
Accuracy and repeatability
Using AB Dynamics' path-following and differential GPS, absolute lateral position accuracy in a straight line is 2cm or better. In cornering, lateral positional accuracy is typically 10cm or better, with absolute repeatability of approximately 2cm.
Path-following even works on snow and low-friction surfaces
Working with our clients at winter proving grounds, AB Dynamics has shown that its path-following system works reliably and accurately even on low friction surfaces like snow. The algorithm recognises vehicle oversteer and understeer, automatically applying corrective steering to stay on the path.
Our customers use path-following to evaluate vehicle behaviour and stability control systems on frozen surfaces, as well as for testing winter tyres on a range of surfaces.
Path-following with speed control
By combining an AB Dynamics steering robot with pedal robots such as the CBAR, a path can be followed with accurate and repeatable speed control, time after time, lap after lap. This makes the test driver’s job easier and produces more repeatable data.
Motion packs
Path following requires a suitable GPS-corrected motion pack. AB Dynamics can offer its ultra-compact Pinpoint motion pack, and path following can also be used with motion packs from OxTS, GeneSys and iMAR. Other motion packs can be integrated on request.
Applications for path-following
AB Dynamics developed path-following in 2000 initially for vehicle dynamics testing. Since then, we’ve worked with our customers to develop and enhance this technology, and today it forms the basis for how many different types of tests are performed.
