The robot, which can wrap around and lift objects as delicate as a glass vase or as bulky as a watermelon, is made from inflatable, vine-like tubes that extend, twist, and coil around a target. A larger version has even shown it can safely lift a human from a bed, opening the door for applications in eldercare and rehabilitation.
The design centers on a pressurized box placed near the object to be picked up. From this box, soft tubes inflate and grow outward, similar to turning a sock inside out. As they extend, the tubes twist and wrap around the object, then route back toward the base, where they're clamped in place and wound up gently, creating a sling-like hold that lifts the object without forceful gripping.
This approach allows the robot to handle a variety of fragile and heavy items, squeeze into cluttered spaces, and operate in environments where conventional robotic arms might struggle.
The researchers envision a wide range of use cases for this robot in the future, from agricultural harvesting to warehouse logistics. But for now, they're exploring the robot’s potential in healthcare settings, especially in assisting caregivers with one of the most physically demanding tasks: transferring a person out of bed.
Transferring a person out of bed is one of the most physically strenuous tasks that a caregiver carries out. This kind of robot can help relieve the caretaker, and can be gentler and more comfortable for the patient.
Kentaro Barhydt, Ph.D. Candidate, Department of Mechanical Engineering, MIT
Barhydt and his co-first author from Stanford, O. Godson Osele, present the new robotic gripper design in Science Advances.
Open and Closed
The Stanford team, led by Professor Allison Okamura, pioneered the development of soft, vine-inspired robots that grow outward from their tips. These robots are built from thin yet durable pneumatic tubes that inflate and extend using controlled air pressure. As they grow, the tubes can twist, bend, and navigate through tight, cluttered spaces, making them ideal for complex environments.
Until now, most vine robots have been explored for tasks like safety inspections and search-and-rescue missions. But at MIT, Kentaro Barhydt and Professor Harry Asada, whose lab focuses on assistive robotics for eldercare, began to ask a different question: could these flexible robots help address the physical challenges of caregiving, particularly when it comes to safely lifting someone out of bed?
In many nursing and rehabilitation settings, transferring a person out of bed requires a caregiver to roll the patient onto their side, slide a sling or sheet beneath them, then hook it to a mechanical lift that hoists them up. It's labor-intensive and physically demanding for the caregiver, and not always comfortable for the patient.
The MIT and Stanford team envisioned a new approach: what if a robotic vine could gently snake under and around a patient on its own, creating a kind of supportive sling - no manual repositioning required?
To make that possible, the team had to address a key limitation in current vine robot designs. Most are what engineers call “open-loop” systems - long, flexible tubes that can extend and maneuver but don’t connect back to themselves or their base. To lift a person or object securely, the robot would need to form a “closed loop,” essentially wrapping fully around the target and anchoring back to its source.
Barhydt and his collaborators saw an opportunity to combine both behaviors. In their new design, detailed in the study, the robotic vine starts in an open-loop mode: it grows and twists around an object, or even burrows beneath a person lying in bed, to establish a gentle hold. Then, it continues to grow back toward its base, where it latches into place, creating a closed loop that can be safely retracted to lift the object or person.
By merging open- and closed-loop functionality, the robot gains a new level of control and adaptability, allowing it to position itself flexibly and then switch into a stable configuration to carry out the lift.
People might assume that in order to grab something, you just reach out and grab it. But there are different stages, such as positioning and holding. By transforming between open and closed loops, we can achieve new levels of performance by leveraging the advantages of both forms for their respective stages.
Kentaro Barhydt, Ph.D. Candidate, Department of Mechanical Engineering, MIT
Gentle Suspension
To demonstrate the capabilities of their open- and closed-loop design, the team built a large-scale robotic system specifically designed to lift a person safely from a bed. The setup features two pressurized boxes mounted at either end of an overhead support bar. Inside each box, an air pump inflates and unfurls thin, flexible tubes that extend downward toward the head and foot of the bed.
These vine-like tubes can be carefully controlled to maneuver under and around the person lying in bed. Once in place, they extend back up to their respective boxes, effectively forming a loop. Each tube then passes through a clamping mechanism that locks it in position. Finally, a built-in winch system retracts the vines, gently lifting the person in a soft, supportive cradle.
This system showcases how the robot's unique ability to grow, wrap, and then close the loop allows it to safely and comfortably handle a task that’s traditionally labor-intensive and physically taxing for human caregivers.
Heavy but fragile objects, such as a human body, are difficult to grasp with the robotic hands that are available today. We have developed a vine-like, growing robot gripper that can wrap around an object and suspend it gently and securely.
Harry Asada, Ford Professor, Engineering, MIT
Osele adds, “There’s an entire design space we hope this work inspires our colleagues to continue to explore. I especially look forward to the implications for patient transfer applications in health care.”
“I am very excited about future work to use robots like these for physically assisting people with mobility challenges. Soft robots can be relatively safe, low-cost, and optimally designed for specific human needs, in contrast to other approaches like humanoid robots,” added co-author Okamura.
Although the team's initial focus was on addressing challenges in eldercare, they quickly recognized the broader potential of their design for a wide range of grasping tasks. In addition to the large-scale system for lifting people, the researchers developed a smaller version of the vine robot that can be mounted onto a standard commercial robotic arm.
This compact version has demonstrated impressive versatility, capable of gently gripping and lifting objects that vary widely in size, weight, and fragility. The team successfully used it to handle a glass vase, a watermelon, a kettlebell, a stack of metal rods, and even a playground ball. The flexible vines can also navigate through cluttered environments, reaching into bins or tight spaces to retrieve specific items.
These results suggest that the robot’s unique combination of adaptability and gentle grasping makes it well-suited for applications beyond healthcare, including manufacturing, logistics, and automated material handling.
“We think this kind of robot design can be adapted to many applications. We are also thinking about applying this to heavy industry, and things like automating the operation of cranes at ports and warehouses,” said Barhydt.
This study received partial support from the National Science Foundation and the Ford Foundation.
Loop closure grasping: Topological transformations enable strong, gentle, and versatile grasps
Video Credit: Massachusetts Institute of Technology
Journal Reference:
Barhydt, K., et al. (2025) Loop closure grasping: Topological transformations enable strong, gentle, and versatile grasps. Science Advances. DOI: 10.1126/sciadv.ady9581. https://www.science.org/doi/10.1126/sciadv.ady9581