The POSIM multibeam sonar plugin uses a ray-based point-scattering model to generate intensity-range data. The original research is credited below.

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POSIM backend status · 2026-10-01: experimental WGPU development is now in POSIM PR #6, transferred from DAVE PR #44. The new PR is unmerged. Neither POSIM main nor the published PR #5 validation images includes WGPU.

CUDA requires NVIDIA hardware, compatible driver/toolkit and built plugin targets. Apple Silicon Linux containers do not expose native macOS Metal. Four CUDA-conditioned paths were outside the headless candidate acceptance set; 14/14 headless passes do not certify sonar.

See POSIM Quickstart & Backend Support for installation and backend limits.

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Earlier candidate measurements (historical)

On Apple M2/Metal, the candidate range-axis remapping reduced CPU–WGPU RMSE from 1.4532 m to 0.0540 m (96.28%) across 16 conditions × 5 frames. Contributor validation on an NVIDIA RTX 4060 reported 0.0552 m for CUDA and 0.0574 m for WGPU/Vulkan; the two reported RMSE values differ by 0.0022 m. These are pre-merge validation results, not features released in POSIM main.

These earlier measurements are retained as recorded, not re-measured by the 2026-10-01 documentation update and not evidence that the published PR #5 images contain WGPU.

Key Features

• Physical sonar beam/ray calculation with the point scattering model
  • Generating intensity-range (A-plot) raw sonar data
  • Publishes the data with UW APL’s sonar image msg format
• NVIDIA CUDA core GPU parallelization
• Experimental WGPU backend in POSIM PR #6 (unmerged; previous DAVE #44 discussion retained)

Below is a diagram showing how the plugin is structured and how CUDA is utilized to perform the sonar calculations.

Original Research paper

• Choi, W., Olson, D., Davis, D., Zhang, M., Racson, A., Bingham, B. S., … & Herman, J. Physics-based modelling and simulation of Multibeam Echosounder perception for Autonomous Underwater Manipulation. Frontiers in Robotics and AI, 279. 10.3389/frobt.2021.706646

POSIM build and implementation references

• POSIM Sonar — Build & Troubleshooting
• POSIM CUDA Sonar — Optimization Reference

Getting started

The implementation carried in POSIM main uses CUDA and requires an NVIDIA/CUDA environment. On Apple Silicon (ARM64), the CUDA-only build does not install the multibeam sonar demo launch files or the multibeam_sonar_system library. The experimental WGPU path is reviewed in POSIM PR #6 and is not part of POSIM main or the published validation images.

To install the required system dependencies, follow the instructions below:

• POSIM Native Installation : Native Local Installation Manual