Overview:

I started learning ROS in 2017 and first purchased two mini advanced 7-DOF desktop robot arms (inspired by 7Bot) for the purpose of learning ROS and integrated almost all my previous work into ROS Kinetic on Ubuntu16.04 . Due to the expiration of Ubuntu 16.04 EOL (end of life: April 2021), a lot of ROS packages, especially ROS robot controller spawners, new python scrips, are not easily upgraded. Therefore, I upgraded my ROS workspace to ROS Melodic (Ubuntu 18.04) . Most ROS nodes were developed by C++ .
To run ROS on an embedded system, I managed to get Ubuntu 18.04 running on the Raspberry Pi 4B mini-computer, then installed ROS Melodic on it and eventually migrated all ROS applications to Raspberry Pi platform.
Hardware Specification:
Hex7Bot dual Robot arm (platform) consist of two identical robot arm ( Hex7Bot). Hex7Bot is a 6-axis arm with 7 single-axis TTL-controlled servos and the motor 4-7 have been upgraded
with HLS3606M (manufacturer: FeeTech)for more torque controls.
| Parts Name | Qt | Description |
| Robot body | 2 | Hex7bot Robot arm Assembly |
| Raspberry Pi 4B | 2 | Raspberry Pi 4B Mini-Computer (Host ) |
| Arduino Atmega2560 | 2 | Motor control board (Client) |
| 3D depth camera | 1 | RealSense D435 Depth Camera |
| OS on MicroSD | 2 | RaspberryPI OS image: Ubuntu 18.04/ROS Melodic |
| AC Power adapter | 2 | Power Adapter 6V x 10A |
- Cable Connection:
Single Robot Arm System Structure:
Software Architecture
- Robot Model : Robot arm forward/inverse Kinematics with Common Interface (BaseRobot Model):

- Robot Control (Ros_control – ROS1)
- Robot Hardware Interface:
- 3D Vision:

- Perception Processing:

- Off-line Programming and Simulation with Rviz, Gazebo and MoveIt!

- HMI ( Human Machine Interface): Support Keyboard, joysticks , remote control over Web App
- Deep Learning with TensorFlow:
- Workspace ( ROS1)
ROS Running Graphic Representation:
- ROS Running Graphic Representation ( For one arm):
BOOK:
BOOK:
All above work was summarized in the book ( Published 04/26/2016):
The ROS Cookbook:Building Intelligent Robot Arms f ….
Shi, Peitao and Shi, Helen
ROS Cookbook: Building Intelligent Robot Arms from Scratch. (Amazon)
Buy Now(IngramSpark)










