Unitree G1 humanoid robot performs live gallbladder removal

What actually happened in this experiment?

Researchers at the University of California San Diego performed the world's first laparoscopic gallbladder removal on a live animal using general-purpose humanoid robots, not the specialized surgical systems that have dominated operating rooms for decades. The study, published July 8 in Nature, used two Unitree G1 robots, a Chinese-made platform that stands 1.5 meters tall and weighs 27 kilograms. The team ran two separate procedures: one where a G1 robot worked alongside a human surgeon, and a second where two robots completed the operation entirely by remote control with no human at the table. Neither procedure required switching to conventional open surgery.

The robot used in the study, nicknamed "Surgie," relied on a teleoperation framework built by Ph.D. student Lucas Zekai Liang. Visual markers attached to the surgical entry point let the robot's head-mounted camera track the pivot location in real time, while an inverse kinematics solver continuously adjusted arm position. That software-based approach replaces the rigid mechanical structures that purpose-built surgical robots use to maintain precise instrument angles through the abdominal wall.

How does the cost and size compare to existing surgical robots?

The contrast with Intuitive Surgical's da Vinci system is stark. A da Vinci unit weighs around 816 kilograms, costs between $1.8 million and $2.5 million, and requires a specially configured operating room with a dedicated technical team. The base Unitree G1 sells for $13,500. Even with the surgical hand adapters and modifications the UCSD team added, total cost comes to roughly $67,000, less than one-tenth the price of a da Vinci.

A 27-kilogram robot that costs $67,000 performing surgery that previously required an $2 million machine changes the entire calculus of who can afford robotic-assisted care.

That price gap matters beyond hospital budgets. Co-corresponding author and UCSD Assistant Professor of Surgery Shanglei Liu pointed to the system's small footprint as a practical advantage for deployment in remote clinics, battlefield settings, or even space, places where a multi-ton specialized machine is simply not an option.

What are the real limitations right now?

Precision is not the problem. In controlled lab tests, Surgie's weighted error on a two-handed task scored 4.53, nearly identical to the da Vinci Research Kit's 4.59. Among surgeons in the test group, error was actually lower when using the humanoid robot. The gap is speed and stability. The system's control latency runs about 156 milliseconds, and breathing movement from the animal caused the virtual pivot point to drift repeatedly during live surgery. Each drift required pausing the procedure for several minutes to recalibrate, pushing total operating time well beyond what a mature da Vinci system requires.

Liu drew a historical comparison to put that in context: the first robotic laparoscopic cholecystectomy in 1997 took six hours, while the same procedure now takes 30 minutes. The implication is that speed is an engineering problem with a known solution path, not a fundamental barrier. Still, the road from animal trials to human patients involves additional hurdles: sterility protocols, greater force output from the robot arms, and more robust handling of communication latency all need work before any regulatory body would consider human use.

Why does this matter for the robotics industry?

The surgical robotics market has been built around expensive, single-purpose machines sold to well-funded hospitals in wealthy countries. That model leaves roughly 67 percent of the global population without access to basic surgical care, according to the UCSD paper. The United States alone is projected to face a shortage of more than 10,000 surgical specialists by 2036.

UCSD Professor Michael Yip, who leads the broader research program, argued that a general-purpose humanoid platform changes the value proposition entirely. A specialized surgical robot does one thing. A humanoid robot can perform the procedure, then fetch instruments, then help clean the room. "Our goal is to develop autonomous surgical assistants and create the operating room of the future, where humanoid robots and humans work as an integrated team to provide surgical services to those in need," Yip said.

For the broader humanoid robot industry, this is a significant proof of concept. Companies like Unitree have positioned their platforms as general-purpose machines for logistics and manufacturing. A peer-reviewed demonstration of surgical capability, even at an early stage, opens a credible path into healthcare, one of the largest and most regulated markets on earth. Established players like Intuitive Surgical, Medtronic, and Johnson and Johnson have invested heavily in purpose-built systems. A low-cost, lightweight alternative that can be shipped to a rural clinic or a forward operating base represents a genuinely different competitive angle.