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Welcome to the MOIRs-MARK-2-URDF wiki!

Files Required in order for URDF visualization:

1. moir_mark2_urdf_ros/config/module_config.yaml
2. moir_mark2_urdf_ros/urdf/modular_robot.urdf.xacro
3. moir_mark2_urdf_ros/urdf/material.xacro
4. moir_mark2_urdf_ros/meshes (folder containing meshes for the modules for visualizing)
5. moir_mark2_urdf_ros/scripts/ElementTree_pretty.py
6. moir_mark2_urdf_ros/scripts/moir_modular_composition_generator.py
7. moir_mark2_urdf_ros/scripts/moir_modular_generator_DH.py The generated files will be saved in moir_mark2_urdf_ros/urdf/generated/

Using DH parameters

Write DH parameters in module_config.yaml

robot_name: mod<n>r_name  
offset_length: < in meters>    
dh_config:
- /alpha /a /d /theta /H or L  

Note: The DH table order is as follows.

Twist angle	Link length	Offset	Joint angle	Module Variant

• n is the number of DoF of the configuration. Example: mod6r_standard or mod2r_planar
• Use /alpha in radians, for 90: 1.56
• Robot base is formed, just as a stand. Height of the stand is decided by the offset length.

Navigate to the directory: moir_mark2_urdf_ros/scripts python moir_modular_generator_DH.py Navigate to the main workspace.

source devel/setup.bash
cd /your_ws/src/moir_mark2_urdf_ros/urdf/generated
roslaunch urdf_tutorial display.launch model:=mod<n>r_name.xacro

taa daa...

Using Modular Sequence

This methods skips the usage of DH and allows the designer to assemble modules as desired in whatever twist angles. To use this, first navigate to the directory: moir_mark2_urdf_ros/scripts

    python moir_modular_compostion_generator.py

The following set of Instructions will be asked to the designed in the terminal. Put the appropriate values in instructed format given below.

   - Enter the name of the robot: mod<n>r_<name>
   - Enter the type configuration: 1 or 2 or 3 or 4
   - Enter the initial offset length: (in meters)
   - Enter the number of modules required: <n>
   - Enter module configuration: refer below

for any arbitrary configuration, Best is to refer type of the configuration as 4 the enter module configuration will take command as follows,

Modular Variant and Unit	Twist_1	Twist_2	Link type

for example:

1. E, as in Table 4 of this article

  - Enter the name of the robot: mod4r_E
  - Enter the type configuration: 4
  - Enter the initial offset length: 0
  - Enter the number of modules required: 4
  - Enter module configuration: h1 0 0 0 and then enter, add again until the table is complete. 

Modular Variant and Unit	Twist_1	Twist_2	Link type
H1	0	0	0
H2	0	0.785	0
L2	0	-0.523	0
L2	0	0	0

2. F, as in Table 4 of this article

  - Enter the name of the robot: mod4r_F
  - Enter the type configuration: 4
  - Enter the initial offset length: 0
  - Enter the number of modules required: 4
  - Enter module configuration: refer below

Modular Variant and Unit	Twist_1	Twist_2	Link type
H1	0	0	0
H4	0	0.523	1
L4	0.785	0.785	0
L2	0	0	0

Once the file is generated, Navigate to the main workspace.

source devel/setup.bash
cd /your_ws/src/moir_mark2_urdf_ros/urdf/generated
roslaunch urdf_tutorial display.launch model:=mod<n>r_name.xacro