Hello Robot, the team behind the Stretch mobile manipulation platform, have announced the release of Stretch 4.
Available now for $29,950, Stretch 4 is an open-source robotics platform designed for researchers, developers, and application engineers building the next wave of Physical AI applications for general purpose robotics.
“In the last few years, Physical AI has brought us videos of robots doing amazing stunts. But these videos are missing something critical – the people the robots are meant to benefit,” says Aaron Edsinger, co-founder and CEO of Hello Robot.
“With Stretch 4, Hello Robot is delivering a robot designed specifically to operate safely shoulder-to-shoulder with people. It is compact, lightweight, ready to work, and a delight to use.”
A pathway to robots in everyday life
From the beginning, Hello Robot has worked toward a future in which robots enhance life for everyone, including children, older adults, and people with disabilities. To this end, Hello Robot has been piloting Stretch to support individuals with severe mobility impairments.
Controlling the robot through a mobile phone app, users have increased agency, accomplishing tasks such as fetching a drink of water, closing the blinds, and feeding themselves.
In developing Stretch 4 to meet the needs of these users, Hello Robot also is tackling some of the most difficult challenges in robotics: safe, reliable, and intuitive human-robot interaction.
Their practical approach – rejecting the complexity of humanoid forms in favor of functional, lightweight, and safe design – positions Stretch to become a pathway to robots becoming a welcome part of everyday life.
“Designing Stretch 4 to meet real needs in homes has resulted in a platform with unprecedented potential,” according to Charlie Kemp, CTO and co-founder of Hello Robot.
“With Stretch 4, developers can confidently target new applications in which robots closely collaborate with people. People are not an afterthought; they are the primary reason for Stretch 4’s design.”
Working safely, shoulder to shoulder
Stretch 4 is a distinctive robot featuring a telescoping arm, an omnidirectional base, and a sophisticated sensor array – including two hemispherical 3D LiDAR sensors, three high-resolution cameras, and six laser line sensors.
The architecture follows the “sensor-rich” philosophy utilized by Waymo to achieve high-fidelity safety in autonomous driving, standing in contrast to the more minimalist, vision-only approaches seen elsewhere in the industry.
“You can’t cheat physics when it comes to robot safety,” added Edsinger. “The inherent physical properties of full-size humanoids means they can become potentially dangerous in the event of a system failure.
“In contrast, Stretch 4 has a unique, compact, and low-potential-energy design. It is intrinsically much safer when things don’t go as expected – as they invariably will.”
Stretch 4 is a major redesign based on customer feedback, resulting in a versatile and easy-to-use platform for developers. Notable features include:
Wide-angle 3D sensing head
- The sensor head is fully-calibrated and rigidly fixed with respect to the arm and mobile base, simplifying autonomy
- Two hemispherical 3D LiDAR and global-shutter fisheye RGB cameras observe the surroundings, dramatically reducing blind spots even when the arm is in use
- One central, high-resolution RGB camera observes the gripper’s workspace, supporting dexterous manipulation
Omnidirectional mobile base
- The mobile base provides quick and smooth motion in any direction
- The large 20 cm wheels let the robot traverse indoor terrain, including carpets, rugs, and thresholds
- Six laser-line sensors ring the base, sensing small hazards on the floor such as cords, rugs, and drop-offs
Greater speed, reach and end-of-arm options
- The arm, lift, and base operate at twice the speed of Stretch 3, while the total reach has been extended by 10%
- The robot features 8 redundant degrees of freedom plus the gripper, including an ambidextrous wrist with an integrated depth camera that can be configured for either left- or right-handed operation
- A new quick-release mechanism allows users to efficiently swap between a compliant gripper, parallel jaw gripper, and a tablet interface
New power and compute system
- An Nvidia Jetson Orin NX runs Physical AI models on the robot
- An all-new power system enables up to eight hours of runtime
- A docking station now supports autonomous self charging, enabling long-duration deployments
A capable platform that is ready to work
Hello Robot launched the first Stretch robot in 2020. Since then, more than a thousand users from 23 countries have pioneered the future of mobile manipulation with Stretch.
Stretch is an adaptable platform that can be used in unique ways. Henry Evans, a non-verbal person with quadriplegia, had this reaction: “I’ve had the privilege of working with the Hello Robot team for some time, and what strikes me about Stretch 4 is its versatility.
“It has an omnidirectional base, which gives it the freedom to move effortlessly, in any direction, and it has simple, intuitive controls, which make it feel like an extension of my body.
“For me that is particularly important, because Stretch 4 represents my only means of interacting with my physical environment. Stretch 4 gives me greater confidence, deeper independence, and a life with more possibility.”
Henry Evans is the co-founder of Robots for Humanity.
Berkeley Artificial Intelligence Research (BAIR) Lab is a leading academic research center advancing the foundations and real-world applications of artificial intelligence, with work spanning robotics, computer vision, machine learning, and human-centered AI systems.
Nur Muhammad “Mahi” Shafiullah, postdoctoral researcher, Berkeley AI Research (BAIR), UC Berkeley, says: “During graduate school, I spent nearly five years bringing robots into homes for experiments and demos.
“At that time, the only mobile robot I’d trust in my parents’ home was Stretch. When it comes to living and working alongside humans, safety-first design will win. To get there, we need more robots that prioritize people above all else.
“I’m glad Hello Robot continues its invaluable work in this direction, and I hope Stretch 4 helps users and researchers move closer to a world where everyday home-helper robots are no longer a dream, but a reality.”
University of Illinois Urbana-Champaign is home to a cutting-edge research center focused on how to develop next-generation smart homes that would allow people of all ages and abilities to live fuller, healthier, and autonomous lives.
Wendy Rogers, Khan Professor of Applied Health Sciences, University of Illinois Urbana-Champaign, says: “We are exploring the potential of Stretch to enable independence for older adults with a range of abilities and limitations; how a robot can support that in practical, everyday ways.
“Our research with Stretch is advancing understanding of how robots can and should function in home environments, with consideration for user needs and preferences.”
Available now for developers
Stretch 4 is available for purchase today for $29,950 at www.hello-robot.com. The Stretch platform empowers developers with open-source code, excellent support, and a global community.
