QtVlm autopilot VLM

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You can program VLM's autopilot

  • Through the menu 'Route>Edit a route' and send POIs to autopilot more help
  • Directly through Autopilot function:

1- Select "Boat > Autopilot" buttons. This will open a new dialog:


2- Click on the '+' button:

3- Click on the drop box 'Constant Heading':

  • If you choose 'Constant Heading' or 'Constant Wind Angle' you have to enter an angle in the next field.
  • If you choose 'Ortho' 'Best VMG' or 'VBVMG',
    • you can capture coordinates directly in the next field, or
    • you can click on the WP button and choose a POI directly on the map

4- Enter the date at which the instruction sould be executed. Pilototo4.png

5- Validate. This will send instructions to VLM's autopilot

Autopilot sends Waypoints to the VLM Server



  • The Autopilot can receive up to six waypoints from the Routes > Autopilot Tab.
  • The command sequence is Select the Route > Right Click > Pick Edit > Route Tab > Check VBVMG
  • Then go to Autopilot Tab > Load Auto > Send which uploads the WP to the VLM server.
  • Additional WP's can be added from the Boat > Autopilot window.
  • The autopilot will execute the waypoints dependent on the Pilot mode, current grib and boat polar.
  • When the last waypoint is reached several things can happen dependent on what has been entered into the last waypoint Position and Next heading. See below.

Boat > Autopilot > Autopilot Instructions Window

Pilot Mode

  • 1. Constant Heading - Steers on a constant bearing (West = 270°). on a rumb-line course.
  • 2. Constant Wind Heading - Steers on a constant wind heading on a variable course determined by grib.
  • 3. Orthodromic Pilot - Uses a great-circle which is the shortest distance between any two points.
  • 4. Best VMG - The bearing that results in the fastest approaching speed to the goal using the current wind.
  • 5. Very Best VMG - Integrates a tack to the goal and minimize the duration.

Heading / Angle - Usually Greyed out with '0.0' (not used). Pilot Mode -Constant Heading uses this.


  • Latitude If '0' the next WP is the race's next closest gate, and there are no intermediate WP.
  • Longitude If '0' the next WP is the race's next closest gate, and there are no intermediate WP.

Next Heading - Usually this angle is entered when doing Route > Autopilot Tab > Load Auto > Send

  • If there is a "Heading-to-follow-after-WP" entered, then the boat will be set in heading mode with this value. -- Nice, but if the wind happens to come from that direction, you might not move a lot...
  • If there is not such value defined (i.e. it has been set to "-1"), then the boat will keep the same navigation mode (VBVMG, VMG or ORTHO) as the one it had before reaching the WP, and will use that mode toward the closest point of the next race gate. --Nice again, but if there is land between the boat and the next gate that might create problems.
  • Note: A WP is considered as 'reached' in VLM when the distance between the boat and the WP is less than or equal to the distance the boat sailed during the previous crank (vacation). So in fact the WP is always reached *before* the boat hits it.

Copy Instruction, Paste Instruction, Select Mark allows a convenient way to pick a WP fro

Boat > Autopilot

To Check or Edit WP uploaded to the Autopilot on the VLM Server. The best way to check and modify what instructions have been sent from a Route to the Autopilot server, is to use Boat > Autopilot which will show the list of waypoints on the server that the VLM engine uses to calculate the boats progress. "Edit All" button on the WP you'd like to check. All parameters can be changed..