SIMRunning SimulationsOpenSim
Driver Inputs
Create OpenSim Driver Input timelines for throttle, brake, steering, and optional gear control.
Driver Inputs are reusable OpenSim control timelines. They are different from Drivers: a Driver stores driver profile limits, while a Driver Input stores prescribed control traces over time.
If your team calls these control inputs, use the Driver Inputs screen in 4ACE.
Before you start
- Select the correct team.
- Decide the control sequence you want OpenSim to run.
- Use seconds for segment times.
- Use percent for throttle and brake, degrees for steer angle, and integer gear numbers when gear is enabled.
Create a Driver Input
- Open Driver Inputs from the sidebar.
- Select New.
- Enter Name.
- Add Notes when the timeline needs context.
- In Driver Inputs, define required segments for:
- Throttle.
- Brake.
- Steer angle.
- Optional: turn on Specify gear channel if gear should come from the Driver Input.
- Add gear segments when gear channel is enabled.
- Review the charts above each channel.
- Select Save.
After saving, the Driver Input appears in the Driver Inputs table and in OpenSim setup.
Segment fields
| Field | What it means | Notes |
|---|---|---|
| Segment | Readable summary of the time and values in the row. | Generated from row values. |
| Start | Segment start time. | Seconds. Must be 0 or greater. |
| End | Segment end time. | Seconds. Must be greater than Start. |
| From | Value at Start. | Uses channel unit. |
| To | Value at End. | Uses channel unit. |
When you add a segment, it starts at the previous segment end when one exists. The new segment lasts 5 seconds by default.
Channel reference
| Channel | Unit | Required | Value range | Notes |
|---|---|---|---|---|
| Throttle | % | Yes | 0 to 100 | Required for save. |
| Brake | % | Yes | 0 to 100 | Required for save. |
| Steer angle | ° | Yes | -700 to 700 | Required for save. |
| Gear | n/a | Only when enabled | Integers 1 to 8 | Off lets the model handle gear shifts. |
Timeline rules
- Name is required.
- Throttle, Brake, and Steer angle each need at least one segment.
- Segment times cannot be negative.
- A segment start must be before its end.
- Segments in the same channel cannot overlap.
- Adjacent segments can share a boundary, but the next start value must match the previous end value.
- Gear values must be whole numbers from 1 to 8.
OpenSim duration is the latest visible channel segment end time. If no segment extends the timeline, duration is at least 1 second.
Use a Driver Input in OpenSim
- Open Simulations.
- Select New.
- Choose OpenSim.
- In Setup, select Vehicle, Ambient, Driver, and Driver Input.
- Review the Driver Input preview before continuing.
Troubleshooting
| Problem | What to check |
|---|---|
| Save shows Fix Driver Input before saving | Review the validation list and fix each channel. |
| Throttle, Brake, or Steer angle error | Add at least one segment to each required channel. |
| Segment overlap error | Move the segment start after the previous segment end. |
| Boundary value error | Make adjacent values continuous at the shared time. |
| Gear error | Use integer gear values from 1 to 8, or turn off Specify gear channel. |
| Driver Input missing from OpenSim setup | Confirm the correct team is active and the Driver Input saved successfully. |