Manipulators description

This package contains two very basic manipulators:

• Theta-rho manipulator has 1 angular DoF and 1 prismatic DoF.

• Theta-theta manipulator has 2 angular DoFs.

Install

To run the package you have to download it inside your catkin_ws/src folder. You can use:

~catkin_ws/src $ git clone https://github.com/narcispr/manipulators_description.git

or just download the ZIP file and uncompress it in catkin_ws/src folder. Notice that the name must be manipulators_description!

Once you have the package downloaded it is a good habit run the catkin_make command (from the root of your workspace) to check if something has to be compiled or generated.

~catkin_ws $ catkin_make

or if you use the catkin build tools use

~catkin_ws $ catkin build

Visualize the manipulators

This package do not contain any piece of code just the URDF files and a launch. To execute it run the following command:

$ roslaunch manipulators_description view_theta_theta.launch
or
$ roslaunch manipulators_description view_theta_rho.launch

By default, the launch file runs the node joint_state_publisher_gui that allows you to move the manipulator manually. However, if you want to run your own controller (anything publishing /joint_state messages) firts comment this node in the launch file.

Kinematics

Denavit-Hartenberg parameters

• Theta-rho:

DoF	theta_i	d_i	a_i​	alpha_i​
1	theta_1	0.5	0.0	Pi/2
2	Pi/2​	d_2	0.0	0.0

• Theta-theta

DoF	theta_i	d_i	a_i​	alpha_i​
1	theta_1	0	0.40	0
2	theta_2​	0	0.45	Pi/2