The AutoDrive dialog is displayed when you use either of the AutoDrive modes. It allows you to set turning criteria, and to switch between arc and bearing modes.
The Minimum Radius setting is used to limit the turning radius. Enter a value in the box and press the Tab or Enter key. You can select Inner Wheel or Outer Wheel to limit the inside or outside wheel tracking radius respectively, Inner Body or Outer Body to limit the inner or outer body envelope radius, or Centerline to limit the radius at the centre of the steered axle.
Clearance Offset shows a clearance zone around the vehicle. You can edit the offset value. The clearance envelope applies to both body and chassis. An offset envelope will be displayed outside the body static envelope and another outside the chassis static envelope. If you want to use a clearance envelope during driving, see System Settings: Paths: AutoDrive.
The Turn Onto Bearing control is used to switch back and forth between arc and bearing modes.
Freehand Turn (the default) is selected to turn immediately and drive straight to the cursor. In this case the vehicle still turns as tightly as current constraints allow but there is never any straight section preceding the turn.
Picked Alignment is used to specify the alignment by picking a line or line segment from the drawing. You can align the vehicle parallel to the selected line or depress the Perpendicular To button to align the vehicle perpendicular to the selected line. Click Pick Alignment and then pick the alignment.
Turn Through Angle is used to turn as late as possible through a fixed angle. Select the angle from the list or enter a value. The vehicle will turn as tightly as possible, subject to current constraints, through the specified angle and then drive straight to the cursor. As you move the cursor away from the last target point the sections preceding and following the turn adjust accordingly.
After the next target point has been picked following selection of a non-freehand bearing mode the bearing mode will switch automatically back to freehand mode.
Turn onto WCB (whole circle bearing) is used to turn as late as possible onto a fixed bearing. Select the heading from the drop down list or enter a value. Again, the vehicle will turn as tightly as present constraints allow onto the specified heading and then straighten and drive to the cursor. The current angle and bearing are displayed in the adjacent read-only boxes.
Side Overturn is used to start the turn with opposite lock, thereby reducing trailing axle cut-in. By adjusting the side overturn distance you can alter the size of the deviation.
Exit Overturn is used to continue the turn beyond the required exit angle prior to turning back onto the required exit angle. As with side overturn this reduces trailing axle cut-in.
Max Overturn Angle can be adjusted to alter the severity of the overturn. This is the maximum opposite lock bearing deviation. For example, if the vehicle commences a right turn from straight ahead on a bearing of 0 deg, a max overturn angle of 30 deg would allow the vehicle to turn left onto a maximum bearing of -30 before turning back. Note that the maximum overturn angle may not be reached when using smaller overturn distances.
Override Rear Steering can be used if the vehicle has manually controllable secondary steering. Select the option to switch it on, and clear it to switch it off. You can also do this by clicking the mouse wheel. When secondary steering is switched on the dialog expands to show more fields. The secondary steering may involve adjusting a linkage ratio or the wheel angle directly. Either way the slider shows the range of values. The current value is displayed in a box labelled either Linkage Ratio or Wheel Angle depending on the vehicle definition. The easiest way to adjust the secondary steering value is to use the mouse wheel but you can move the slider if you prefer.
Show Settings can be selected to check what other constraints are set. When selected, the dialog expands to show the main settings.
Forward Predictive Turning turns on the Predictive Turning envelope for forward maneuvers, and Reverse Predictive Turning does the same in reverse. You can change the settings for these in the AutoDrive settings. Note that for articulated vehicles the predictive turning envelopes are based upon a percentage (set in AutoDrive settings) of the tightest turn possible without the vehicle over-articulating. Thus it may be possible to turn tighter than the 100% envelope for a short distance.
SnapDrive is used to enable snapping to Autodesk Vehicle Tracking objects. The path will snap to parking bays and valid routes on roundabouts.
Turn On Spot is used to disable any turn transitions for just the current step. The steering will turn instantaneously at the start of the step only. As soon as you click the next target position the option will be reset.
Limit Steering To Percentage or Limit Steering To Angle controls can require an edit to the indicated value. Note that limiting the steering by percentage is vehicle independent whereas limiting to a specific angle is not.
Limit Articulation To Percentage or Limit Articulation To Angle controls can require an edit to the indicated value. Note that limiting the articulation by percentage is vehicle independent whereas limiting to a specific angle is not.
Limit Forward Turn Rate and Limit Reverse Turn Rate can be cleared to allow steering to be turned while the vehicle is stationary. When these limits are disabled, you should be able to see the steering pointer (if displayed) at the last picked position changing as you move the cursor to change the current position.
Dynamic Effects are useful when modelling higher speed maneuvers (above about 15 km/h or 9 mph). This limits the turn radius to allow for passenger comfort.
Offset Forwards TP (Tracking Point) or Offset Reverse TP are used to offset the tracking point.
If you need to modify a value that is not listed click the Current Model button.