TimeDelayEstimation

This delay estimation node estimates a time delay from inputs to outputs for accel, brake, and steer.

Input / Response

The following topics are used to estimate the delay.

• /vehicle/raw_vehicle_cmd: used as accel/brake target value
• /control/control_cmd: used as steer target value
• /calibration/vehicle/accel_status: used as accel observed value
• /calibration/vehicle/brake_status: used as brake observed value
• /vehicle/status/steering: used as steer observed value
• /calibration/vehicle/is_engage: used to check the driving operation status

output.

For users, the TimeDelay.msg output contains the following items:

• time_delay: Estimated time delay.
• mean: Mean value of the estimated time delay
• stddev: Standard deviation of the estimated time delay
• is_valid_data: Validity determination of the current data
• first_order_model_coefficients：size 2 array of model coefficients(b,k,t)
• second_order_model_coefficients：size 2 array of model coefficients(m,b,k,t)

In addition, the following items are output for developers.

• Mean average error of delay estimation
• Standard deviation of the mean error of delay estimation

These values can be confirmed in rqt_multiplot, described below.

How to Run Time Delay Estimator

Note: You need to build the Autoware beforehand.

The following command will start the delay estimation node.

ros2 launch time_delay_estimator time_delay_estimator.launch.xml is_showing_debug_graph:=true

Change the estimator type

You can decide the estimator_type with the following parameters

• “cc” : Cross Correlation
• “ls” : Least Squared
• “ls2” : Least Squared Second

Note: Only “cc” Cross Correlation will display the debug graph

How to check the estimated delay

The necessary information is plotted in the rqt_multiplot, which displays the following information from top to bottom.

• First row: Input data processing results examination
• Second row: Estimation results confirmation
• Third row: The confidence level of the estimation results
• Fourth row: Input/output error after delay compensation

Input data processing results examination

Check the input and output data. It is also used to adjust parameters of the estimation logic.

• input raw : input data
• response raw : response data
• input processed : input data after compensation (*)
• response processed : response data after compensation (*)
• data stddev : standard deviation of the data used for estimation (used to determine validity)
• is valid data : Whether the data is valid or not
  • 0.0 : invalid because the standard deviation is less than the threshold (*_min_stddev_threshold).
  • 1.0 : valid because the standard deviation is greater than the threshold (*_min_stddev_threshold).

(*) Smoothing, normalization, and resampling are applied as preprocessing.

You need to adjust the value of *_min_stddev_threshold according to the standard deviation to determine the validity of the data.

Estimation results confirmation

Check the estimation results.

• delay : Time delay estimated at each step
• average : Average of the time delays
• stddev : Standard deviation of the estimated delay

File truncated at 100 lines [see the full file](https://github.com/autowarefoundation/autoware_tools/tree/main/vehicle/time_delay_estimator/README.md)

Changelog for package time_delay_estimator

0.6.0 (2026-02-14)

0.5.0 (2025-12-30)

0.4.0 (2025-11-16)

0.3.0 (2025-08-11)

0.2.0 (2025-03-24)

0.1.0 (2025-01-28)

• unify version to 0.0.0

• chore: sync files (#11) Co-authored-by: github-actions <<github-actions@github.com>> Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

• feat: add vehicle, control and localization calibration tools (#22)

  • add vehicle control localization tools
  • style(pre-commit): autofix
  • fix pre commit
  • Fix to pass cspell about localization
  • ignore words from spellcheck
  • ROS2 -> ROS 2
  • feat: convert autoware_auto_msg to autoware_msg (#42)
  • merge
  • delete autoware_auto

  * style(pre-commit): autofix ---------Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

  • add prefix to vehicle_info_utils
  • style(pre-commit): autofix
  • fix: add s to VehicleInfoUtil

  * fix

  Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com> Co-authored-by: Shintaro Sakoda <<shintaro.sakoda@tier4.jp>> Co-authored-by: SakodaShintaro <<rgbygscrsedppbwg@gmail.com>> Co-authored-by: tomoya.kimura <<tomoya.kimura@tier4.jp>>

• Contributors: Yutaka Kondo, awf-autoware-bot[bot], yabuta