About the Driving Machine
You can use Adams Car to study full-vehicle behavior for many different aspects of vehicle development, such as handling, ride, and durability.
Adams Car offer several standard full-vehicle analyses (ramp steer, straight line braking, and so on) allowing engineers and analysts to quickly characterize certain vehicle attributes. In addition to standard full-vehicle analyses, the Driving Machine supports an XML event file that lets you create your own custom full-vehicle analyses. These analyses are typically built from a number of mini-maneuvers, which when simulated in succession, define a meaningful vehicle test. An example of such a test could be a braking-in-turn analysis, which would consist of the following mini-maneuvers:
1. Drive along a road in a straight line, maintaining a constant velocity. When a constant velocity has been achieved for a specified amount of time and within a prescribed tolerance, end the first mini-maneuver.
2. Start the second mini-maneuver by steering the vehicle onto a prescribed radius and maintaining the same velocity. When the velocity has stabilized for a set amount of time and within a prescribed tolerance, end the second mini-maneuver.
3. Start the third mini-maneuver by maintaining the previous radius and velocity from the second mini-maneuver. After a two-second delay, apply the brake to achieve a desired longitudinal deceleration while maintaining the radius from the second mini-maneuver by controlling the steering wheel.
For a human driver, this is quite a simple task: you simply drive in a straight line, turn the steering wheel, and then apply the brake. In the Adams Car environment, you have more control over the driving event. Such an analysis requires a reasonably complex event file.
Looking at the mini-maneuvers described above, the control attributes for each mini-maneuver are.
■Steering wheel has to keep the vehicle straight. Throttle has to maintain vehicle speed. Gear, clutch, and brake are not used.
■Steering wheel has to steer the vehicle, then control the radius of turn. Throttle has to maintain vehicle speed. Gear, clutch, and brake are not used.
■Steering wheel has to maintain the radius of turn (steering motion will change during braking based on the understeer/oversteer characteristics of the vehicle). Brake has to be applied and controlled to achieve the desired lateral acceleration. Throttle has to be lifted. Application of the clutch will need to be considered also.
The Driving Machine permits a fine level of control over the full-vehicle model. This control has historically been exercised by using a .dcf file, which is based on the TeimOrbit data file standard. The Driving Machine now uses XML event files to describe mini-maneuvers. You can still access .dcf files, however, Driving Machine automatically converts them to XML event file format.