Of all the elements of a car that give it the level of dynamic response and safety expected by a discerning driver, steering is one of the most important. Because of this, steering test programs are an essential part of achieving required standards and Anthony Best Dynamics (ABD) has expanded its range of steering robots to support them. Its new SR60 Torus is designed to decrease test setup time, aid vehicle operation, and enhance the safety of vehicle handling tests.
Differing from conventional steering robots, the SR60 Torus combines a large diameter hollow center with the ability to clamp the unit to an existing steering wheel, keeping the steering wheel airbag in place, stated the company at the system’s launch.
To reduce test setup time, ABD wanted to avoid the need to remove the original steering wheel or disable the steering wheel airbag. Using the new system, the airbag can safely deploy through the center of the steering wheel without the robot motor becoming detached from it. The new system is said by ABD to overcome the drawback of sensor deactivation that occurs when the standard steering wheel is removed from some vehicles—and it allows the driver to access the steering wheel mounted controls.
A direct drive continuous rotation brushless motor with low-friction bearing is used to power the SR60 Torus. No gears or clutches are necessary. The vehicle can be driven manually between tests using the integrated steering rim.
Performance envelope of the motor is similar to ABD’s conventional SR60 motor and is designed to exceed the specification requirements of NHTSA’s fishhook and FMVSS126 tests that require a maximum of 60 Nm @ 1200 o/s. The motor is compatible with ABD’s Omni and Mono in-vehicle controllers and can be used in conjunction with the company’s brake, accelerator, clutch, and gear change robots.
The new Torus and the existing SR60 model each complement the SR30 steering robot, which is the smallest model in the range and designed to match the performance of a typical human driver.
Peak torque of the SR60 Torus and SR60 robots are approximately twice that of the SR30 and are suitable for heavy-duty applications that may require high speed and torque, such as the NHTSA rollover and stability control tests. ABD produces steering robots with torque outputs up to 150 N·m (111 lb·ft) that can be engineered to meet a variety of requirements.
The SR60 Torus is designed to apply accurate and repeatable inputs to a vehicle’s steering system for testing its transient handling behavior on a test track or for evaluating the steering system itself. A wide range of test profiles can be applied to the vehicle’s steering system with “very precise control” for direct comparisons between vehicles, stated ABD. A database is used to store the test definitions and specific vehicle information for each vehicle tested and to keep track of stored results.
The software enables the driver to define and run new tests quickly via a library of standard tests designed to meet NHTSA and ISO 7401 requirements. They include single sine, sine sweep, step, and ramp inputs. Test profiles can be recorded from direct driver input using a learn mode or played out from data stored in an ASCII file. The robot can also follow an external analogue voltage input.
The SR60 Torus steering robot can also be used with ABD’s Path Following option, which uses a GPS-corrected motion pack to give real-time feedback on vehicle position and heading. This enables the robot to control the vehicle and follow a predefined path.