Some new features and suggestions of webots in underwater applications

[AaaGss]

Hello, development team. I'm a researcher working on underwater applications. Recently I have been using webots software, and I recently encountered several problems as follows:

1. Underwater vehicles are often used, but I did not find the existing model in the software, so I designed a simple one by myself, but I still sincerely hope that the development team can integrate a ready-made underwater vehicle in webots. If you want, I can open source mine to everyone.
2. There seems to be no simulation model such as sonar and forward looking sonar in the software, but this is very common in underwater, just like using cameras on land. I hope the development team can integrate forward looking sonar and sonar sensors in the software, which will undoubtedly make the ecology of the software better and better.
3. Since 2020a, the software has removed most resources in order to save volume, but every time it is used, it may have to download resources online, which is very bad, especially when the network environment is not good. So I sincerely hope that all resources can be packaged together, although the download time is a little longer, but the use will have a better experience. If you can, it is recommended to do two versions, one version with resources, generally without resources, so as to provide users with a better choice.

[omichel]

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