urdf-viz

Visualize URDF(Unified Robot Description Format) file. urdf-viz is written in Rust-lang.

Install

Install with cargo

If you are using rust-lang already and cargo is installed, you can install by cargo install.

cargo install urdf-viz

If you don't use mesh other than .obj, .stl, and .dae files, you can skip install of assimp by disabling the assimp feature like below.

cargo build --no-default-features

Note: When the assimp feature is disabled, materials are not fully supported yet.

Pre-requirements for build

Common

You need cmake to use assimp (mesh loader). It can be skipped if you use --no-default-features, but it will make it fail to show mesh files other than .obj, .stl, and .dae.

On Linux

If you have not installed ROS, you may need cmake, xorg-dev, glu to compile assimp-sys and glfw-sys.

sudo apt-get install cmake xorg-dev libglu1-mesa-dev

On Windows

You need freetype.lib in your PATH, which is required by freetype-sys. You can find binaries here

On MacOS

Install freetype by brew.

brew install freetype

Download binary

You can download prebuilt binaries from the release page. Prebuilt binaries are available for macOS, Linux, and Windows.

Install via Homebrew

You can install urdf-viz using Homebrew tap on macOS and Linux:

brew install openrr/tap/urdf-viz

How to use

urdf-viz command will be installed. It needs rosrun and rospack to resolve package:// in <mesh> tag, and it uses xacro to convert .xacro file into urdf file. It means you need $ source ~/catkin_ws/devel/setup.bash or something before using urdf-viz.

urdf-viz URDF_FILE.urdf

It is possible to use xacro file directly. It will be converted by rosrun xacro xacro inside of urdf-viz.

urdf-viz XACRO_FILE.urdf.xacro

For other options, please read the output of -h option.

urdf-viz -h

If there are no "package://" in mesh tag, and don't use xacro you can skip install of ROS.

GUI Usage

In the GUI, you can do some operations with keyboard and mouse.

• l key to reload the urdf from file
• c key to toggle collision model or visual mode
• Move a joint
  • set the angle of a joint by Up/Down key
  • Ctrl + Drag to move the angle of a joint
  • change the joint to be moved by o ([) and p (])
• Inverse kinematics (only positions)
  • Shift + Drag to use inverse kinematics(Y and Z axis)
  • Shift + Ctrl + Drag to use inverse kinematics(X and Z axis)
  • change the move target for inverse kinematics by , or .
• r key to set random joints
• z key to reset joint positions and origin
• Move view point
  • Mouse Right Drag to translate view camera position
  • Mouse Left Drag to look around
  • Scroll to zoom in/out

Web I/O interface

You can set/get the joint angles using http/JSON. Default port number is 7777. You can change it by -p option. (jq is used for JSON formatter in the following examples)

Set joint angles

POST the JSON data, which format is like below. You have to specify the names of joints and positions (angles). The length of names and positions have to be the same. You don't need write all joint names, it means you can specify a part of the joints.

{
  "names": ["joint_name1", "joint_name2"],
  "positions": [0.5, -0.1]
}

You can try it using curl.

$ curl -H "Accept: application/json" -H "Content-type: application/json" -X POST -d '{"names": ["r_shoulder_yaw", "r_shoulder_pitch"], "positions": [0.8, -0.8]}' http://127.0.0.1:7777/set_joint_positions | jq
{
  "is_ok": true,
  "reason": ""
}

Get joint angles as JSON

The result JSON format of getting the joint angles is the same as the Set method.

$ curl http://127.0.0.1:7777/get_joint_positions | jq
{
  "names": [
    "r_shoulder_yaw",
    "r_shoulder_pitch",
    "r_shoulder_roll",
    "r_elbow_pitch",
    "r_wrist_yaw",
    "r_wrist_pitch",
    "l_shoulder_yaw",
    "l_shoulder_pitch",
    "l_shoulder_roll",
    "l_elbow_pitch",
    "l_wrist_yaw",
    "l_wrist_pitch"
  ],
  "positions": [
    0.8,
    -0.8,
    -1.3447506,
    -1.6683152,
    -1.786362,
    -1.0689334,
    0.11638665,
    -0.5987091,
    0.7868867,
    -0.027412653,
    0.019940138,
    -0.6975361
  ]
}

Set Robot Origin

$ curl -H "Accept: application/json" -H "Content-type: application/json" -X POST -d '{"position":[0.2,0.0,0.0],"quaternion":[0.0,0.0,0.0,1.0]}' http://127.0.0.1:7777/set_robot_origin
{"is_ok":true,"reason":""}

The order of the quaternion elements is w, i, j, k.

Get Robot Origin

$ curl http://127.0.0.1:7777/get_robot_origin
{"position":[0.2,0.0,0.0],"quaternion":[1.0,0.0,0.0,0.0]}

Get URDF Text

curl http://127.0.0.1:7777/get_urdf_text

Gallery

Dependencies

• kiss3d: urdf-viz is strongly depend on kiss3d, which is super easy to use, great 3D graphic engine.
• nalgabra: linear algebra library.
• k: kinematics library which is based on nalgabra. It can load URDF files using urdf-rs.
• assimp-rs: assimp rust interface. kiss3d supports .obj files natively, but urdf contains dae or stl files. These files are converted to kiss3d mesh model by assimp-rs
• urdf-rs: URDF file loader.
• structopt: super easy command line arguments parser.