Hello Robot unveils Stretch 4 robot that can actively assist people at home and on the job

Hello Robot, the organization behind the Stretch mobile manipulation platform, announced the release of Stretch 4.

The company said that Stretch 4 is an open-source robotics platform designed for researchers, developers and application engineers to build the next wave of physical AI applications for general-purpose robotics.

A pathway to robots in everyday life

Since its founding in 2017, Hello Robot has said that it 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 said that it has been piloting Stretch to support individuals with severe mobility impairments. Controlling the robot through a mobile phone app, the company said that its users have increased agency, accomplishing tasks such as fetching a drink of water, closing the blinds and feeding themselves.

“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,” said 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.”

In developing Stretch 4 to meet the needs of these users, Hello Robot said that it is also tackling some of the most difficult challenges in robotics: safe, reliable, and intuitive human-robot interaction. The company said that its 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,” said Charlie Kemp, co-founder and CTO 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

Hello Robot said that Stretch 4 is a distinctive robot featuring a telescoping arm, an omnidirectional base and a sophisticated sensor array - including two hemispherical 3D lidar, three high-resolution cameras, and six laser line sensors. The company said that this architecture follows the "sensor-rich" philosophy utilized by Waymo to achieve high-fidelity safety in self-driving, contrasting the more minimalist, vision-only approaches seen elsewhere in the industry.

“You can’t cheat physics when it comes to robot safety,” Edsinger said. “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.”

Hello Robot said that Stretch 4 underwent a major redesign based on customer feedback, resulting in a versatile and easy-to-use platform for developers. The company said that notable features in Stretch 4 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 end-of-arm tools between a compliant gripper, a 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 8 hours of run time
  • A docking station now supports autonomous self-charging, enabling long-duration deployments

A platform that is ready to work

Hello Robot said that it launched the first Stretch robot in 2020. Since then, the company said that over 1,000 users from 23 countries have pioneered the future of mobile manipulation with the Stretch adaptable platform.

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,” said Henry Evans, a non-verbal person with quadriplegia and the co-founder of Robots for Humanity. “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.”

Click here to learn more about Stretch 4.