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2017-02-25 18:47:17 -0600 received badge  Scholar (source)
2017-02-25 18:47:12 -0600 answered a question Ackermann Steered Vehicle Controlled by ROS

So my final solution was to keep using the ackermann_vehicle package. If you tune the PID in the .yaml files then it seems to work fine for a larger vehicle. There is still a problem with heavy weight (so the vehicle can be large in size, intertia and everything else but not in weight) but that seems to be more widespread within Gazebo.

If anybody has a fix for the drifting associated with the heavy weight that would be beyond awesome!

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2017-02-14 21:38:40 -0600 asked a question How to prevent model drifting?

Hey!

I am trying to simulate a model of an ev (like the polaris ranger) using ackermann steering. I currently have a functional simulation that moves around and responds to messages as required. Unfortunately I recently realized that one of the people I am working with set the weight to 50kg instead of the more realistic 500kg which makes it a lot more likely to tip over when going around corners at speed.

However...when I bump the weight to 500kg, everything goes out the window. The model bucks a little bit when it spawns and then proceeds to slide around despite the wheels being still.

Does anybody know a solution to prevent this from occurring?

Thanks!

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2017-01-17 11:34:19 -0600 asked a question Ackermann Steered Vehicle Controlled by ROS

Hey!

I am very new to Gazebo and I am try to make / find a package that will allow me to simulate an ackermann steered vehicle in gazebo and control it through ROS. I was hoping for something along the lines of the database polaris ranger EV.

There are a variety of existing packages out there but most seem unfinished or outdated (don't work with ROS kinetic, etc.).

The best I could find is the ackermann_vehicle package but it uses a small RC car as the model which isn't exactly what I was looking for and apparently has problems scaling it up to a larger vehicle due to assumptions of size in the code.

Does anybody know of a good package I could use that would do this or a way to edit an existing package to change it to control the polaris ranger ev?

Thanks for any help you can provide!

2017-01-17 11:34:17 -0600 commented answer Trying to replicate the ackermann steering from DRCSim

Hey! Would you be able to upload or share a final package? Thanks so much!

2017-01-17 11:34:16 -0600 asked a question Change model used in ackermann_vehicle package

Hey!

I am pretty new to Gazebo and in desperatly in need of help! I am trying to create / find a model of an ackermann-steered vehicle that I can connect to ROS. The ackermann_vehicle package operates perfectly for this. However the model for it is that of ... well essentially a remote control truck that is described in a urdf.xacro file. I was hoping to replace this with a different model (for instance the database provided model for the polaris ranger ev) but can't seem to figure out how without re-writing the whole polaris ranger model in a urdf.xacro file.

From what I can tell what happens is:

The 1st .launch file calls spawn_model and gives it the model information as a parameter from another launch file. This 2nd launch file gets that parameter by reading the urdf.xacro file. These both interact with a lot of other components along the way to get it working which looks very complicated.

There are probably some necessary components in the model for the plugin to work so I was first just trying to just replace the urdf.xacro file with an sdf equivalent (created by editing and saving without any changes the model that is spawned by the launch file) and get that working and then I can add the required components to the sdf of the ranger.

I could go on for a while about all the different things I tried but essentially none of them worked.

So my question is: How can I change the ackermann_vehicle package to spawn and control a model of the polaris ranger ev instead of the current vehicle it creates?

Alternatively is there a different package that takes the same msg format (i.e. this) but will more easily allow me to interchange the model it controls?