README.md

Arm URDF Package

Authors:

• Jonathan Qiao
  • Email: jonathanqfxw@gmail.com
• Yousif El-Wishahy
  • Email: yel.wishahy@gmail.com

This README has been copied and modified from the old arm repo.

Descripton:

This package is meant to be an envorment to develope the URDF of the arm.

The vast majority of the URDF is defined in ob1_arm_description/urdf/arm_no_base.xacro.urdf. The xacro file contains a xacro macro with name arm and parameter prefix (string), prefix will be used to defined unique arm. This file acts like a function definition but for URDF

The xacro file with path arm_urdf/urdf/arm_no_base.xacro is used to generate the urdf.

Converting Onshape CADs to URDF

Onshape-to-robot is a python package used to convert onshape cads to urdf using onshape apis. This was used to generate the urdf for our custom robotic arm. Modifcations were made after.

Useful links:

• Documentation
• https://youtu.be/C8oK4uUmbRw

Usage:

Example: define a new arm with prefix arm1 and attach it to world origin

<!-- world origin is just a designated link that is set as "fixed frame" in rviz. 

World origin link is named "base_link" in this case -->
<link name="base_link"/>

<!-- use xacro to define arm with prefix "arm1" -->
<xacro:arm prefix="arm1"/>

<!-- attach arm1 to world origin  -->
<joint name="base" type="fixed">
    <parent link="base_link" />
    <child link="arm1_base" />
</joint>

View the model in rviz:

rviz: a renderer that comes installed with ros

Execute following command in termial:

# only need to be sourced once for every new terminal session
source <path to workspace>/devel/setup.bash

roslaunch arm_urdf arm_urdf.launch

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