Rethink Robotics | Industrial Products
Human-centered Design
Too often, systems are designed with a focus on business goals, fancy features, and the technological capabilities of hardware or software elements. Human-centered Design (HCD) is an approach to problem solving, commonly used in design and management frameworks that develops solutions to problems by involving the human perspective in all steps of the problem-solving process. It is the practice of understanding the customer at the center of your defined product or service, and making them the focal point. It is an iterative process and involves refinement and putting concepts in the hands of users to acquire feedback to reach the best solution with the best chance of having it embraced by the user. Getting to know and understand users in order to express their needs is the dawn of an opportunity. To deliver a solution that meets and even exceeds those needs is the goal.
Meet Baxter
Baxter is an adaptive, collaborative manufacturing robot- a “cobot”. Baxter has cameras, sensors and sophisticated software that enable it to “see” objects, “feel” forces and “understand” tasks. The result is a robot that automatically adapts to changing environments.
Baxter isn’t programmed using teaching pendants or engineering algorithms. It’s trained manually by people by moving its arms and ‘showing’ it what to do. Whether it’s a simple pick and place task, or a more complex and integrated order fulfillment job, the entire process is defined by hand. Baxter can be trained to hold a part in front of a scanner or camera, to take a specific path between points, or to pick things from a shelf or machine… all manually. At the core of this process is Human-centered Design.
I worked with the Rethink Robotics team to develop his hands called “grippers” and the user guides to facilitate installation of those grippers. I worked with the engineering, UX and training teams to devise some physical product solutions to test both with Baxter and with users who would be setting Baxter up by using a hands-on “teaching” process instead of programming tasks. Once the grippers were finalized, I worked to refine and create artworks for the directions for use.
Frame the Task
I worked with the team at Rethink Robotics to explore the world of end effectors and grippers. With a library of about 100 or so parts from the consumer, medical and industrial worlds, a basic understanding of the competitive landscape of existing robotic grippers, and a defined gripper technology of a linear actuator, our task began. How could Baxter pick all these different items up and put them down?
Ergonomics
Determining finger length was driven by the objects, and by ergonomics. Understanding human hand geometry and applying what we learned to the fingers for Baxter helped us build a solid platform for the list of tasks we needed to accomplish, and to plan for future tasks as well.
4 Fingers
The next evolution of concept work focused on selection between 4 sets of fingers, including 2 widths and 2 lengths. Though slightly more complex in the selection process, this concept gave us a better mounting technique and increased finger strength, while also addressing the additional challenge of grip clearance and overlap when picking up an object.
Choosing the Right Fingers
Because we had 4 finger types to choose from, we dug in and came up with a strategy to help users pick the right fingers based on the object they planned to pick up. A series of iterations on infographics helped to hone the selection process. Choosing fingertips was simplified significantly and based on shape and material that the object was made of.
Directions For Use (DFU)
To accompany user testing, we produced several iterations of step by step directions for use. The strategic vision for Baxter was to be so simple that you didn't need instructions, so the user guides were simple tips and pointers combined with line drawing images to make the process easy.
User Testing
We conducted several rounds of user testing. Some were focused on guides alone to ensure understandable word choices. Others reviewed task analysis and clarity of communication of steps and order. Some tests were conducted with Baxter to ensure the guides worked harmoniously with the hardware. Each test provided feedback that was utilized to simplify both the guides and the overall system.
New Needs = New Kits
As systems evolve, user needs change and evolve as well. As part of that evolution process. Rethink Robotics discovered that the vacuum cup gripper was in need of a revised approach. The single cup is still an option, but a new generator and array cup configuration kit addresses the need to pick up larger items and more than one item at a time in industrial applications. To address this need, the gripper was recently re-designed and the Retrofit Guide and Array Guide were designed to address those needs and to provide a baseline for continued growth.
Understanding the User
Baxter is a new kind of robot. More user-friendly, Baxter is often trained by a line worker without programming experience and limited computer expertise, so using a hands-on approach makes the teaching new tasks aspect much more accessible and easy to learn. The GUI uses expressions and thought bubbles to make task teaching easy to understand for the lineworker. The same approach was applied to designing the grippers.
Electric Parallel Gripper
Lots of experimentation, whiteboard sketch sessions and discussion led to the concept of using fingers. After all, Baxter is a friendly robot and that's how humans pick things up. We looked at several concept directions and then focused to using 2 sets of fingers or 4 sets of fingers...
2 Fingers
Based on the object to be picked up, the line worker must select one of 2 different lengths of fingers. Selection from 2 options rather than 4 options seemed much more intuitive from the user perspective. As we explored the manufacturing realities, it was the mounting technique and the fixed area for mounting hardware, combined with the strength requirements that caused us to step slightly away from this direction.
4 Fingers
Thinking about the user process for a line worker to assemble a gripper to complete a specific task was complex. Task analysis, order of assembly, number of parts required, and establishing intuitive rationale for the selection process was the key to making a complex task easy to perform. This new direction met all of the requirements and was refined for user testing, and eventually production.
Build to Test
In similar fashion, we designed a vacuum cup gripper to use for objects which were difficult to manipulate with the fingers approach. Captured fasteners, use of a single allen key size, intuitive graphic placement and one-way fit paved the way for ease of use. With both kinds of prototype grippers, we began testing with Baxter and with users to see what we could improve upon.
User Guides
Because users are trained on the basics when they make a purchase, most people found that after completing the process once, they didn't feel they needed the instructions except as occasional reminders and support. In that regard, the instructions were designed as reminders and guides, and provided springboards creativity and adaptability.
Gripper Kits
Once the task analysis and user testing was complete, we designed kits to organize, present and store the components to each gripper. When you order Baxter, you choose the Electric Gripper Kit or the Vacuum Cup Gripper kit depending on your needs. Each kit contains the basics to get you started, and creativity is encouraged to define new iterations of accessories to meet additional needs.
