The Design of Stretch: A Compact, Lightweight Mobile Manipulator for Indoor Human Environments
This work addresses the problem of limited adoption of mobile manipulators in indoor settings by reducing barriers like size and cost, though it appears incremental as it builds on existing robotic concepts.
The authors tackled the challenge of creating a compact, lightweight, and affordable mobile manipulator for indoor human environments, resulting in the Stretch design that reduces size, weight, and cost while supporting various tasks, with empirical validation from real-home deployments.
Mobile manipulators for indoor human environments can serve as versatile devices that perform a variety of tasks, yet adoption of this technology has been limited. Reducing size, weight, and cost could facilitate adoption, but risks restricting capabilities. We present a novel design that reduces size, weight, and cost, while supporting a variety of tasks. The core design consists of a two-wheeled differential-drive mobile base, a lift, and a telescoping arm configured to achieve Cartesian motion at the end of the arm. Design extensions include a 1 degree-of-freedom (DOF) wrist to stow a tool, a 2-DOF dexterous wrist to pitch and roll a tool, and a compliant gripper. We justify our design with anthropometry and mathematical models of static stability. We also provide empirical support from teleoperating and autonomously controlling a commercial robot based on our design (the Stretch RE1 from Hello Robot Inc.) to perform tasks in real homes.