Flexible 6-DOF Desktop Robot for Research:myCobot 320 Review

1. Introduction

With the rapid development of artificial intelligence and robotics, robots have been widely used in both daily life and industry. From single-arm and dual-arm robots to robotic dogs and humanoid robots, a variety of products have emerged. The myCobot 320, a small robotic arm, stands out for its flexibility and versatility. This article provides a comprehensive review of this robotic arm, covering its design, performance, and practical applications, aiming to help engineers, educators, and professionals in the manufacturing industry better understand its features and appropriate usage scenarios.

2. Product Overview

The myCobot 320 is a 6-degree-of-freedom robotic arm available in two versions: one based on the M5Stack-Basic as an embedded development board, and the other using a Raspberry Pi 4B. Weighing only 3360g, it is lightweight and portable, making it easy to carry. The robotic arm has a maximum payload capacity of 1000g at the end effector, suitable for most experimental setups. Additionally, it allows for the installation of a camera or actuator (such as a gripper or vacuum pump) at the end effector, leaving approximately 600g of available payload capacity. With a maximum working radius of 350mm, the myCobot 320 offers flexible movement in various scenarios.

3. Design and Structure

Let's start by examining its appearance.

The design of the myCobot 320 is highly modern, featuring a streamlined joint structure that gives it a clean and tech-savvy look. Its compact structure gives an impression of flexibility, making it well-suited to integrate into various complex working environments, particularly in human-robot collaborative scenarios. The clever design balances industrial practicality with aesthetic harmony, providing users with confidence and ease when using this collaborative robotic arm.

Compared to other products, myCobot 320 offers a unique all-black version that resembles a strong snake in the dark. Each joint is equipped with high-performance servo motors. The myCobot 320 is an all-in-one robotic arm, with a single complete arm structure that requires no additional materials for assembly, allowing users to deploy it quickly and carry it anywhere with ease.

At the end of the robotic arm, there is a 5x5 LED display, accompanied by an M8 aviation connector. The base features 12 IO ports of 24V each. The M5 version of the myCobot 320 comes with a display screen and three physical buttons for operation. M5Stack, the hardware company behind it, is globally known and has a community of creative users whose DIY projects can inspire the development of custom applications for the robotic arm.

The Pi version is equipped with a built-in Raspberry Pi 4B, pre-installed with a customized Ubuntu operating system. Once connected to a monitor, keyboard, and mouse, users can immediately start developing. Raspberry Pi is well-known in global maker communities, and due to its compact size and powerful performance, it is one of the most popular choices for robotic development. The Raspberry Pi 4B, in particular, stands out as one of the top hardware platforms for robotics.

4. Performance Review

Next, let's take a look at how it performs. The working radius of a robotic arm significantly influences the areas in which it can be applied. From the diagrams, we can see that each joint of the myCobot 320 is independently supported, giving it a much more flexible range of motion compared to some industrial-style robotic arms that prioritize stability.

• Another important factor for a robotic arm is its repeatability. The myCobot 320 can handle a payload of 1000g while maintaining a repeatability accuracy of within 1mm. Despite using servo motors, the myCobot 320 demonstrates high precision performance.

Currently, the myCobot 320 has already undergone one iteration of improvements. The serial communication speed has been upgraded from 100ms to 20ms. Most notably, the internal motion control algorithm of the robotic arm has seen significant upgrades, resulting in greater stability and smoother motion compared to the previous version.

5. Software and Control

With its performance already meeting the demands of certain use cases, let's now focus on the software support for the myCobot 320.

The main points of introduction include:

● Quick Start and Easy Development

One of the most important features of a new product is how quickly users can get started. Taking the Raspberry Pi version as an example, it comes pre-installed with the Ubuntu 20.04 system, which includes all the necessary environments such as Python, ROS, and the pymycobot library. This setup eliminates the need for manual installation, allowing users to dive into development immediately.

For beginners, a graphical programming software called myBlockly has been developed. Even without any coding knowledge, users can control the robotic arm by simply dragging and dropping code blocks.

● Support for Multiple Programming Languages

Every developer is familiar with different programming languages. To address this, control APIs for the robotic arm have been developed across multiple major programming platforms. Whether using Python, Java, C++, or other languages, myCobot 320 is compatible.

Specifically, the Python library, pymycobot, includes nearly all control interfaces one might need. For example, it allows users to control the arm via angles, move it using coordinates, check motor statuses, and adjust motor torque. Since the code is open-source, developers can easily access and use data related to the robotic arm for their projects.

Comprehensive Documentation

myCobot 320 is also supported by extensive documentation through Gitbook and myStudio.

● Gitbook is an electronic manual that provides a complete guide to myCobot 320, from basic mechanics and 3D views to DH parameters and tutorials. After going through the materials, users will be well-equipped to start independent development.

● myStudio is a firmware update and tutorial software. It offers users the ability to update the robotic arm's firmware, and provides access to the latest motion control algorithms from Elephant Robotics.

6. Practical Application Experience

Here are a few case studies that demonstrate the applications developed using the myCobot 320, which might provide some inspiration.

● A Medical Student’s Assistant

In this case, a medical student from Japan aimed to integrate advanced technology with the robotic arm. By attaching an ultrasound device to the end of the arm, they enabled the robot to perform ultrasound scans autonomously. This project replicates the ultrasound process typically done by doctors. If this idea is further developed, it could potentially address the issue of prolonged ultrasound procedures in hospitals, making it a highly meaningful project.

https://www.hackster.io/Elephant-Robotics-Official/mycobot-320-review-a-medical-student-s-robotics-journey-06bd1c

● A Gesture-Recognizing Robot

Imagine if your robotic arm could understand your gestures—how fun would that be? For example, if you opened your hand, the arm could hand you something, similar to Tony Stark's assistant in Iron Man! This particular project involved integrating the MediaPipe gesture recognition algorithm, allowing the robotic arm to execute specific actions based on corresponding hand gestures. This concept showcases the potential of combining gesture recognition with robotic actions in an interactive way.

https://www.hackster.io/gary26/hand-gestures-as-the-remote-controlling-mycobot-320-5dd749

7. Application Scenarios

● Educators and Students:

Given its potential in education and research, the myCobot 320 is particularly suitable for STEM courses and robotics projects in secondary and higher education institutions. Educators can design practical lessons using the myCobot 320 Pi, while students can use it to learn programming, robotic control theory, and foundational artificial intelligence concepts.

● Researchers:

Researchers can utilize the myCobot 320 for prototyping and testing in robotic technology, AI, and automation experiments. Its flexibility and scalability make it an ideal choice for research laboratories.

● Business Demonstrations and Marketing Professionals:

Companies can use the myCobot 320 as a demonstration tool at exhibitions or events, effectively capturing the attention of audiences and showcasing the company’s technological prowess and innovative products.

● Personal Hobbyists and Self-learners:

For individuals interested in robotics, regardless of their technical background, the myCobot 320 offers an accessible and affordable platform to explore programming, robotics, and AI applications.

8. Conclusion and Recommendations

In summary, the myCobot 320 is a highly cost-effective desktop robotic arm, particularly suited for research projects and educational purposes. Its ability to be quickly deployed allows users to dive straight into experimental and teaching applications. However, it is not suited for industrial production or high-intensity scenarios like light manufacturing in the 3C (computer, communications, and consumer electronics) industry. Thanks to its excellent expandability, the myCobot 320 supports secondary development, allowing users to flexibly pair it with cameras, grippers, or other custom end effectors. This robotic arm provides a reliable tool for researchers and educators seeking efficient and adaptable solutions.