The brothers share three extraordinary characteristics that make them unique as assembly-line coworkers. Their safety features let you place them on the line next to people without enclosing them in protective cages. They can be reprogrammed to new tasks by anyone, without any coding or computer input—you literally, just take them by the hand and show them what to do. They don’t need a costly programming engineer tending to them. And finally, their minds (operating systems) aren’t patented, encrypted, or protected by corporate attorneys. Both run on an open source program called the Robot Operating System.

Baxter was introduced by Rethink Robotics almost three years ago. The basic robot is 3' tall and weighs 165 pounds. That’s without the pedestal, which provides stability and mobility. Mounted in the pedestal with its four legs and wheels, Baxter stands 5' 10" - 6' 3" and weighs 306 pounds. Substantial enough to sound dangerous, but there are extra sensors in its hands and arms. These allow Baxter to sense when he hits something, providing enough time to stop without exerting force that would cause damage or injury to whatever is struck. The robot’s motors drive springs instead of hinged bars, and these provide the leeway for a tap-sense-stop sequence that compresses a spring rather than exerting the full force of the motor’s motion. A further prevention system is nestled in a sonar array around Baxter’s head that can sense human movement in his vicinity.

Both Baxter and Sawyer have monitors displaying eyes that indicate what they are doing. The eyes track down to the hands (grippers) when picking up objects, look over to where the next task begins, and even take on a perplexed expression when something isn’t going the way it should.

Of course the monitor eyes don’t see. Instead, there are cameras in the head, in the chest, and at the end of each arm to do that, and they comprise one of the critical systems involved in the way you train either of these robots to do something new. Hold the object you want Baxter or Sawyer to recognize in front of one of the cameras, and then take one of their arms, and move it through the sequence of tasks you want it to perform. As imposing as the arms seem to be, they move with almost no resistance, and the robots memorize the sequence as you proceed.

A very interesting overview of what Baxter can do was presented in a Ted Talk video by the cofounder and CTO (Chief Technology Officer) of Rethink Robotics, Rodney Brooks. “Why We Will Rely on Robots” includes a section on how Baxter learns a new task. It’s worth a look.



Two-month old Sawyer isn’t just a smaller, lighter, one-armed version of Baxter. This latest Rethink factory worker shares many of the safety and functional characteristics of his predecessor, but in a number of ways he’s more precise and smarter.

Noticeably more diminutive, Sawyer weighs only 42 pounds and has a single arm. Rethink Robotics President and CEO Scott Eckert explains, “With Sawyer, we have taken that [relationship of robots and people working together] to the next level, with a high performance robot that opens the door for many new applications that have never been good candidates for automation.”

Some of Sawyer’s advantages were outlined in the company’s press release announcing the robot. “Sawyer features a 4kg (8.8 lb) payload, with 7 degrees of freedom and a 1-meter reach that can maneuver into the tight spaces and varied alignments of work cells designed for humans. Its high-resolution force sensing, embedded at each joint, enables Rethink Robotics’ compliant motion control, which allows the robot to ‘feel’ its way into fixtures or machines, even when parts or positions vary. This enables an adaptive precision that is unique to the robotics industry and allows Sawyer to work effectively in semi-structured environments. In addition, Sawyer features an embedded vision system, which includes a camera in its head to perform applications requiring a wide field of view, and a Cognex camera with a built-in light source in its wrist for precision vision applications. Sawyer’s vision system enables the Robot Positioning System for dynamic re-orientation, and over time will support more advanced features that are inherent to the Cognex system, such as barcode scanning and object recognition.”


Sawyer is currently undergoing extensive field testing and will be available later this summer. Basic cost for the robot is about the same as a Toyota Highlander, $29,000. And that brings up the universal question about robotics replacing people on the assembly line. What human cost will be exacted by the success of Baxter and Sawyer?

There is a discussion of the issue in the Ted Talk, but there’s also an interesting study that was conducted in February 2013 by the International Federation of Robotics (IFR). The title of the study, “Positive Impact of Industrial Robots on Employment,” clearly reflects one of the conclusions that more than two million jobs will be created in the next eight years by robots.

NEWS UPDATE: Tesla’s Whole House Battery

In our last post, we reported on the announcement of Tesla’s Powerwall battery. Within a few days after Elon Musk’s press event, the company reported that it had sold out both battery types and wouldn’t be taking additional reservations until mid-2016. More than 38,000 reservations followed the after-midnight (East Coast) broadcast. Included among those queuing up were approximately 2,800 businesses placing their orders for the commercial size batteries called Powerpacks.

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