Consume speedweight from FW longitudinal config

[Jaeyoung-Lim]

Solved Problem

When trying to enable pure airspeed control with the ROS 2 fixedwing control API, it was apparent that the speed weight of TECS was not exposed by the control API.

• Replaces Set TECS speed weight with setpoint validity #25674

Solution

Expose the speedweight to be configured through the ROS 2 API

Changelog Entry

For release notes:

Feature/Bugfix Airspeed only setpoint for fixed-wing aerial vehicles
New parameter: N/A
Documentation: Need to update the px4 control API.

Alternatives

• We can guess the speedweight depending on the setpoints

Test coverage

Tested in SITL. The following log shows how the vehicle behaves to a equivalent airspeed setpoint of 12m/s

• log: https://review.px4.io/plot_app?log=a30a2ae4-a9fe-48db-bee1-8a309499bfd3

Context

Related links, screenshot before/after, video

[github-actions]

🔎 FLASH Analysis

px4_fmu-v5x [Total VM Diff: 112 byte (0.01 %)]

    FILE SIZE        VM SIZE    
--------------  -------------- 
+0.0%    +112  +0.0%    +112    .text
   +19%     +60   +19%     +60    FwLateralLongitudinalControl::updateLongitudinalControlConfiguration()
  +1.4%     +20  +1.4%     +20    FwLateralLongitudinalControl::FwLateralLongitudinalControl()
  +4.5%     +12  +4.5%     +12    FwLateralLongitudinalControl::getCorrectedLateralAccelSetpoint()
  +3.1%     +12  +3.1%     +12    FwLateralLongitudinalControl::updateParamsImpl()
  +0.0%      +8  +0.0%      +8    [section .text]
  +1.2%      +4  +1.2%      +4    FwLateralLongitudinalControl::parameters_update()
  -0.3%      -4  -0.3%      -4    FwLateralLongitudinalControl::Run()
+0.0%     +55  [ = ]       0    .debug_abbrev
+0.0%    +986  [ = ]       0    .debug_info
+0.0%    +159  [ = ]       0    .debug_line
 -25.0%      -1  [ = ]       0    [Unmapped]
  +0.0%    +160  [ = ]       0    [section .debug_line]
+0.0%    +320  [ = ]       0    .debug_loclists
+0.0%      +8  [ = ]       0    .debug_rnglists
  [NEW]      +2  [ = ]       0    [Unmapped]
  +0.0%      +6  [ = ]       0    [section .debug_rnglists]
-1.3%    -112  [ = ]       0    [Unmapped]
+0.0% +1.49Ki  +0.0%    +112    TOTAL

px4_fmu-v6x [Total VM Diff: 104 byte (0.01 %)]

    FILE SIZE        VM SIZE    
--------------  -------------- 
+0.0%    +104  +0.0%    +104    .text
   +19%     +60   +19%     +60    FwLateralLongitudinalControl::updateLongitudinalControlConfiguration()
  +1.4%     +20  +1.4%     +20    FwLateralLongitudinalControl::FwLateralLongitudinalControl()
  +4.5%     +12  +4.5%     +12    FwLateralLongitudinalControl::getCorrectedLateralAccelSetpoint()
  +3.1%     +12  +3.1%     +12    FwLateralLongitudinalControl::updateParamsImpl()
  +1.2%      +4  +1.2%      +4    FwLateralLongitudinalControl::parameters_update()
  -0.3%      -4  -0.3%      -4    FwLateralLongitudinalControl::Run()
+0.0%     +55  [ = ]       0    .debug_abbrev
+0.0%    +986  [ = ]       0    .debug_info
+0.0%    +159  [ = ]       0    .debug_line
 -25.0%      -1  [ = ]       0    [Unmapped]
  +0.0%    +160  [ = ]       0    [section .debug_line]
+0.0%    +346  [ = ]       0    .debug_loclists
+0.0%      +6  [ = ]       0    .debug_rnglists
-2.2%    -104  [ = ]       0    [Unmapped]
+0.0% +1.52Ki  +0.0%    +104    TOTAL

Updated: 2025-10-08T13:53:55

[Jaeyoung-Lim]

@mahima-yoga Thanks for the review! Is there anything more I can address to get this in?

[mahima-yoga]

Thanks! To me it looks fine 👍 Can you check CI?

[Jaeyoung-Lim]

@mahima-yoga I believe theCI failures are not related to this PR. Thanks!