Cobots rising – What to expect from robots built to work with humans
Collaborative robots may be the beginning of the next major revolution in the robotics space. Robots have been performing repetitive tasks for decades, but through that time, they have been segregated from humans for safety purposes. Programming a robot to do the same thing over and over again is easy, configuring it to recognize when a person is nearby and stop is not so simple. Recent innovation across artificial intelligence, camera, and sensor technologies are fueling a sea change, however, as they lay the groundwork for a robot that can work beside a human.
A Financial Times report puts this kind of environment into perspective by describing the work at one automotive manufacturing plant that uses cobots. On one side of the factory floor, an assembly line of humans is producing parts one component at a time, with each individual taking on the same task over and over again. On the other half of the factory, a few humans are working side by side with cobots. The people are still present, but the cobots are gathering parts and delivering components to the human to allow for rapid assembly.
This type of environment may still be rare, but it is increasingly on the horizon. Citing information from Barclays, the Financial Times said cobots cost, on average, $25,000, making them a fairly valuable option from a fiscal standpoint.
What are cobots?
For the most part, cobots are made up of a couple of arms, a metal-head, and a torso. They can be mounted on a set stand or on a wheeled platform, providing a degree of flexibility. Cameras – often located in arms, allow the cobot to analyze the environment and work side by side with people in a safe way.
How are cobots typically used?
At this stage, cobots take a great deal of inspiration from industrial robots – many of which are just arms – and are primarily designed for the industry. However, there are also applications in the medical sector, as cobots could prove useful in assisting surgeons. For the most part, cobots can pick up and hold items, use basic tools and complete repeatable processes.
What is holding the cobot revolution back?
Cobots are not, at least in most cases, drones. They aren’t autonomous vehicles either. They depend heavily on people to put them where they need to be for work and they are generally fairly stationary with their arms whizzing around to do all of the work. This presents some limitations in how a cobot can be used, but it is important to note that the safety concerns here are legitimate. Advances in artificial intelligence and machine learning will be necessary to ensure that a cobot trying to do a job doesn’t’ inadvertently injure a human in the process.
What makes cobots tick?
The actual robotics technology in cobots will seem fairly familiar to anybody working in industrial settings. The difference comes in the underlying software that governs how the cobot operates. For the most part, solutions will have embedded vision with cameras and similar sensors to help it work, but cobots often use machine learning as well so they can be taught new things.
Leading cobot options
A variety of cobots are available on the market with many being aimed at a specific purpose. A few of the most mainstream models are:
1. Rethink Robotics – Sawyer
Rethink Robotics has a unique brand identity in that it uses touchscreen tablets for the heads of its cobots, and the tablet screen often shows a humanized face to make the robot more relatable. Sawyer is built for precision manufacturing tasks and equipped with Rethink Robotics’ proprietary Intera software to support manufacturing automation. A robot positioning system, force sensing, and Cognex cameras to support embedded vision come together to help Sawyer understand its surroundings.
The cobot has one arm with 7 degrees of freedom. That arm can reach 1260 mm and repeat tasks within a range of accuracy of approximately 0.1 mm with a tool speed of 1.5 m/s. Sawyer is equipped with a wide range of connectivity options, including Modbus TCP and TCP/IP communications ports, 8 digital in I/O ports and 8 digital out I/O ports. Sawyer can handle a 4 kg payload.
2. Rethink Robotics – Baxter
Baxter features the same human-like facial design with a tablet as Sawyer, has 7 degrees of freedom in its arms and also shares Sawyer’s ability to be trained to complete tasks and work safely with humans. The big difference is that Baxter has two arms, with each being able to carry 2.2 kg. Baxter also has cameras in each arm, but it stands out because it is programmed to gain an understanding of the space around it and join up with work cells in the most intuitive way possible. This includes being able to handle part position changes.
An IEEE report delving into how Baxter workers highlighted that base models will typically cost $22,000 and features a slightly more open Robot Operating System that, while not open source, has some libraries for low-level tasks.
The Next Generation Industrial Robot (Nextage) features a head, torso and two arms that can be mounted during production. Each arm can lift 1.5 kg and the arm assemblies provide 6 axes of freedom, creating a full-body degree of freedom of 16 when incorporating the neck and waist of the robot. It can achieve position repeatability within just 0.5 seconds and is explicitly designed for process automation, with the goal of freeing humans to focus on more high-thinking tasks.
Built around the idea of you and me working together, the YuMi cobot is built with safety as a primary focus, with seven-axis dual-arms, flexible hands, and a universal parts feeding system. The YuMi offers integrated Ethernet, a payload capacity of 500 g and a camera and sensor configuration that allows it to work equally well whether it is beside humans or face-to-face with them. With safety as a top priority for YuMi, the robot is designed to stop what it is doing within milliseconds if it identifies an unexpected object or comes into contact with a coworker. Algorithms provide collision-free task guidance as well.
The cobot industry is still a very closed sector. Clear pricing is typically held back until configuration choices are made, most solutions run on highly proprietary software and many solutions are offering fairly common core functionality with a few minor differences that provide differentiation. The $22,000 price tag for Baxter is widely considered an affordable entry point within the sector, and organizations that want to explore cobots must consider the specific operational demands they will face being introducing such a potentially disruptive change.