# Tag Info

6

I'm using Gazebo everyday on my i7 ultrabook; and at home, on i3-7100 desktop. They both have Nvidia GPUs. But fortunately, Gazebo doesn't depend on the GPU. It mostly works on the CPU side. Most Gazebo plugins are built for CPU by default, AFAIK there is only GPU plugin for laser sensor, for 7.0. But I suggest using GPU for better desktop experience while ...

5

I did a little step-by-step tutorial with images, but if my other answer regarding aligning frames didn't work well for you, or the definition of "Front Plane" or "Top Plane" is confusing in Solidworks (spoiler: it is), then consider making your own axes. From the assembly tab, go to reference geometry -> axis, then select the assembly planes to make an ...

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This is more of a Linux than a Gazebo problem. You can just add this line export GAZEBO_MODEL_PATH=[...]/models:$GAZEBO_MODEL_PATH to your ~/.bashrc file. 4 The MATLAB tutorial doesnt cover this aspect well about when you have matlab and gazebo running on the same linux machine with no virtual box. Change your linux ethernet interface ip address statically using: sudo ifconfig eth0 192.168.1.1 netmask 255.255.255.0 assign to ros master the same ip address using: export ROS_MASTER_URI=http://192.168.1.... 4 just use matlab or and python with a set of fixed features in space represented as points. Don't do any vision processing. At this point any vision processing would be overkill. you are making this way too complex. the measurements for your slam can be angles to features. create a set of 30 features randomly populating a 20m by 20m square. make your view ... 3 What you're asking for cannot be accomplished with a PID controller. As I understand your question, you want to be able to choose PID gains that would always produce a "good" trajectory, without tuning. You said it's alright if the motor output is unrealistic, i.e. the motors are "very strong" therefore can produce unlimited torque. ... 3 It looks like most of your parts have no rotation, but some of them do, so I'm going to guess that you didn't mate your assembly to the origin planes in Solidworks. First, on your base plate, open the Solidworks part file and check that the origin planes run through what you want the origin of the part to be. If they don't and it's a pain to re-draw the ... 3 I feel like I'm having to do a lot of work to understand this question. You are trying to simulate two vehicles, and... what's the issue? You are trying to simulate them in Gazebo, right? Have you seen this answer on the ROS website that shows launching two robots in one simulation? As I mention, it's very difficult to read your post, which may explain why ... 3 You asked two questions. Where does Gazebo set the default model path Where should I set the value The second question is perfectly right answered by @Armin Meisterhirn. Best practice is to set the variable in the .bashrc file. The first question, I asked myself as well when starting working with gazebo. In case of the pure Gazebo (no roslaunch, no ... 3 It's a limitation in Gazebo's ability to convert URDF to SDF, Gazebo's native object description format. Frustratingly, RViz works the other way around: it correctly parses URDF colors, but not the SDF fragments inserted by the gazebo tag. One tip though, instead of inlining your material definitions inside links, it's better to define them once at the ... 2 "Save World as" is broken on Gazebo 5.1.0 . You can either install the experimental version of Gazebo 6 using the gazebo6-prerelease package (assuming you are on Ubuntu) or wait for the fix to be released in Gazebo 5.2.0 . The relevant bug on Gazebo issue tracker is: https://bitbucket.org/osrf/gazebo/issue/1593/world-save-as-broken-on-gazebo-510 . 2 You might want to start by checking out AIM - Autonomous Intersection Management by the University of Texas at Austin. It is a simple 2D simulator, but sounds like it has the features you need. Also, you might want to search for civil engineering traffic simulators. I'm sure there are a bunch of them. One more option, you can use something like MASON a ... 2 I've figured out what the problem was. Ubuntu was running a non-default version of python that I had installed for a University python project a couple of years go. I deleted it and now the default version of python is being used, which has solved the problem. 2 It seems that Gazebo 8 is based on Qt5 instead of Qt4. The dependencies should be updated and most importantly, we need to install qwt-qt5 instead of qwt, otherwise our executable is linked to both Qt4 and Qt5 which leads to segmentation fault at start. Here is my PKGBUILD for Gazebo: https://gist.github.com/lyx-x/e6908ef82351b462d4b2e480a43b076c ... 2 As you mentioned in your update, One of the possibilities is to simply add mass to the chassis This works because, at some point, you need a reaction force. An applied force (or torque) at any point in a structure will be transmitted through the structure back to a "fixed" object. The fixed object is generally the Earth, and connection to the Earth is ... 2 The critical part is the registration between depth data and RGB data. If the registration is calibrated properly then you can just extract the depth for the particular target pixel (X,Y), using interpolation for sub-pixel coordinates. See this answer for help with the registration -- it is a common problem that has already been solved. Once you have the ... 2 Answer: The issue is that <origin>, <mass>, and <inertia> tags must be nested inside a <inertial> element for each of the links, instead of being nested in the <link> tag. correct: <link name="${leg_name}_psi_link"> <visual><geometry><sphere radius=".01"/></geometry></visual> <...

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I wanted to do a similar thing to point to a custom Python logging ROS configuration file. From the way I read the documentation you only need to create a .sh script and it should be run by all of the fancier shell environments (e.g. bash with setup.bash). So I added the following line to CMakeLists.txt for my package: catkin_add_env_hooks(logging_env ...

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Modelling a quadcopter is a complex process. I would highly recommend starting with an existing model which is fully operational and then modifying it or extending it to match your design. You're going to need a lot more components than just converting your CAD model to URDF to get the simulation going. There's a large variety of open source examples you can ...

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That is a long list of broad questions. Some of the answers depend heavily on application and personal preference. Assuming you're not using ROS2, then you might consider looking at the ros_control package. Not necessarily to use - just read through their architecture and tutorials for now. It will at least help give you an idea of where to start. As for ...

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Shapes are called links because they're not joints. Keep in mind that these are for robotics and robotic simulations, so the primary concern is going to be expressing the robot's physical structure in such a way that it can be readily used/evaluated by conventional kinematic and dynamic techniques. Notably, Gazebo and the URDF formats are not drafting ...

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It depends. If you're spawning the robot at runtime, either through the spawn_model service or from the Gazebo model database, then you can just just remove the robot from the simulation (click it and hit the <Delete> key), edit the model file and load it again. If it's directly included in the world file, then as far as I can find, no, you cannot reload ...

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You might be confusing Gazebo worlds and models. A world is a single SDF file structured as below: <sdf version="VERSION"> <world name="NAME"> <!-- Included models, links etc. --> </world> </sdf> For example, these are the contents of the sample /usr/share/gazebo-9/worlds/willowgarage.world world file: <?xml ...

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If you mean merging other world's contents into an open world file in the Gazebo GUI, no, there is no way to do that. You can however open the world files in a text editor and just copy contents over. Most worlds are structured as a sequence of <include> tags pointing to external models, so this would be quite easy to do. Notice you can add a <pose&...

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You said: the RGBa values I set in my model in gazebo all have value 1 and you also said: but no values are 255 Which I would expect is correct, because you just said you set them all to 1. Did you mean to scale them from 1 to 255 at some point? Casting 1.0 from float to uint8 will give you 1, not 255.

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It is always recommended to mention your ROS distribution and OS. I believe the error is coming from missing ROS package controller_manager. You can download and install it from the following link https://github.com/ros-controls/ros_control

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Weird motion I'm pretty sure it happen because you make wrong implementation on orientation control. Orientation of end-effector There are 4 main representation of end-effector orientation which is axis angle, rpy (expanded into 6 types), euler angle (expanded into 6 types) and unit quarternion. Normal jacobian derived freshly from forward kinematic ...

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Since you're using gazebo already and it should then be generating simulated time you can ask gazebo to run slower than realtime. In the physics section of your world you can ajdust the maximum realtime factor to tell gazebo to run slower than realtime using the real_time_factor parameter. There's a tutorial on the physics parameters here which you may find ...

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There are several world files with enclosed spaces in the Ignition Fuel website: https://app.ignitionrobotics.org/fuel/worlds The Edifice Demo world is indoors, though perhaps the roof is too high https://app.ignitionrobotics.org/OpenRobotics/fuel/worlds/Edifice%20demo Just about all of the sub-T worlds are in tunnels, which have a roof. https://app....

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Industrial robot controllers (and most "real" robot arm controllers) will have a feedforward term to remove the effect of gravity. Often called gravity compensation. You noticed how necessary this is when you disabled gravity... Check your chain of libraries for an artificial limit being set on the joint effort (torque). You might take a look at moveit! ...

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