Remarkable Trip Through Model Digestive System

The slime robot, which was developed by a research team of CUHK Mechanical and Automation Engineering Department, can deform, grab objects and move, just like the sci-fi movie creatures. Indeed, the robot design was inspired by the movie Venom, but it is different from Venom in a way that it is expected to bring benefit to human beings in the future. 

The secret of Slime Robot

Magnetic particles (NdFeB) and borax were sequentially added to a polyvinyl alcohol (PVA) solution to obtain a self-healing magnetic slime robot. The passive and active deformation capabilities of magnetic slime robots give them a remarkable advantage, not only for adapting to complex terrain environments but also for entering confined spaces in a controlled manner while maintaining their mobility and integrity. Magnetic slime robot aims to offer the opportunity to non-invasively access human tissue to perform medical operations and deliver drugs. Magnetic slime robot can solve the challenges of soft medical robots due to the diverse, dynamic, and complex nature of tissues, biological fluids, and fluid-air interfaces inside the human body, benefitting clinicians and patients. Magnetic slime robot allows easy loading or coating with drugs, imaging agents, or biosensing molecules and the integration of functional micro- or nanomaterials. In addition to the advantage of adapting to the complex environment of the human body, the material of magnetic slime robot and its degradation products are biocompatible, have no negative impact on patient health, and can provide feedback signals to medical imaging devices.

Figure 1. Programming complex shapes of the magnetic slime robot using ferromagnets in disk-, hexagon-, and ring-shapes.

The magnetic slime robot can deform into complex shapes, such as circles, hexagons, and rings, under the configured magnetic field.

Figure 2. Frames of the stretchable behavior of the magnetic slime robot. Scale bar, 10 mm.

The magnetic slime robot can be driven by a permanent magnet (NdFeB) and stretched more than seven times its original length along the direction of the magnet motion.

Figure 3. Overlapped sequential snapshots of videos show that the magnetic slime robot is actuated to navigate through the channel, tube, maze, and uneven surfaces in air. Scale bars, 10 mm.

Under the control of a magnetic field, the slime can navigate freely through various terrains such as narrow channels, confined tubes, complex mazes, and uneven substrates.

Figure 4. Slime robot grasps a wire by curling behavior. Scale bar, 10 mm.

By controlling the rotation of the magnet, the slime robot can be driven to curl.

Figure 5. Slime robot swallows tiny object. Scale bar, 10 mm.

By moving the ring-shaped magnet, the slime robot can be made to open its mouth and swallow small objects.

Figure 6. The healed slime robot can withstand at least up to 8.6 times the stretch deformation. Scale bar, 10 mm.

Slime robots are self-healing and can assemble robots of different compositions.

Media Coverage

The study was widely covered by international media outlets like BBC, Guardian, and New Scientist. The news videos have gained over 10 million views online. The research team was thrilled about the overwhelming response, ‘It is encouraging to know that our study has aroused people’s interest and attention. We will keep it up and explore how the slime robot can be put into practical use in the future.’ 

'Soft robot' made of magnetic slime


Researchers at The Chinese University of Hong Kong have created a “soft robot” made of slime containing magnetic particles, which can be manipulated using external magnets.

What Are Soft Robots?


we’re exploring the advent of soft robots and some of the challenges encountered in creating them

Slime could grab objects inside your body

New Scientist

Slime that can be controlled by a magnetic field can navigate tight spaces and grasp objects, making it ideal for possible uses inside the body

‘Magnetic turd’

The Guardian

Scientists have created a moving magnetic slime capable of encircling smaller objects, self-healing and “very large deformation” to squeeze and travel through narrow spaces. 

This Slime Robot Could Operate in Your Body


This slug-like slime robot created at the Chinese University of Hong Kong could be used to retrieve foreign objects in your stomach and intestines. 

Robot ‘slime magnet’ could save lives

New York Post

Accidentally swallowed a magnetic ball? Not to worry: Hong Kong scientists have created a state-of-the-art “slime robot” that can be magnetically manipulated to retrieve inadvertently ingested objects, among a myriad of other real-world applications.

How Venom inspired scientists


The jellylike substance designed by researchers at the Chinese University of Hong Kong could help retrieve objects from the body

Soft Robot/MR Goggles



Soft Robot from CUHK

BBC Chinese


ABC News: VIDEO: The reconfigurable magnetic slime robot
ABC News: A slime robot that grabs objects inside your body is not an April Fool’s joke, but the rest of these are
BBC Science & Environment: Researchers in Hong Kong create ‘soft robot’ made of magnetic slime BBC Newsaround: Scientists have developed a magnetic slime robot!
Engadget: Magnetic slime ‘robot’ could help recover swallowed objects
BGR: This robot made of magnetic slime is gross, but brilliant
Cover Image India: ‘Slime Robot’ Could Search Our InsidesEsqiure France: ‘La “roomba de las cañerías”: un robot de porquería para limpiarte por dentro
India Today: Slime Robot
CNet Science: Your Next Surgeon Could Be a Slime Robot
CNet Science YouTube: Viral Magnetic SLIME ROBOT explained by Creator
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UpBeat Media Facebook: 中大研「軟泥機械人」 能進入人體取出物體
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HK01: 中大「史萊姆」鬼口水機械人 可進入人體取物 冀兩年內活體實驗
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HKEJ: 外表如糞便 動態如外星生物 機械人專家張立新發明國際爆紅
CUHK in Touch: Slime Robot Makes Remarkable Trip Through Model Digestive System

Research Team

Soft Slime Robot

Prof. Li ZHANG

Prof. Li Zhang is a professor in the Department of Mechanical and Automation Engineering (MAE) and a professor by Courtesy in the Department of Surgery, at The Chinese University of Hong Kong (CUHK). He is also a director of the Shenzhen Institutes of Advanced Technology (SIAT) of the Chinese Academy of Sciences (CAS) – CUHK Joint Laboratory of Robotics and Intelligent Systems. Dr. Zhang received his Ph.D. degree from the University of Basel, Switzerland. During his Ph.D. research, he was also with the laboratory for micro- and nanotechnology (LMN), Paul Scherrer Institute (PSI). Before he joined CUHK, he worked in Prof. Bradley Nelson’s group as a postdoc and then as a senior scientist and lecturer in the Institute of Robotics and Intelligent Systems, Swiss Federal Institute of Technology (ETH) Zurich, Switzerland. Dr. Zhang’s main research interests include miniature robots and devices, milli-/micro-/nanorobotics and their biomedical applications.

Prof. Philip W.Y. CHIU

Prof Philip W.Y. CHIU is currently Professor, Honorary Consultant and Head of Division of Upper Gastrointestinal and Metabolic Surgery, Department of Surgery, Prince of Wales Hospital; Director of Multi-Scale Medical Robotics Center; Director of CUHK Chow Yuk Ho Technology Center for Innovative Medicine and Associate Dean (External Affairs), Faculty of Medicine, The Chinese University of Hong Kong. His research interests include esophageal cancer management, minimally invasive and robotic esophagectomy, novel endoscopic technologies for diagnosis of early GI cancers, endoscopic surgery as well as robotics for endoluminal surgery. Prof. Chiu is first in Hong Kong to perform endoscopic submucosal dissection (ESD) for treatment of early GI cancers in 2004 and Per-oral Endoscopic Myotomy (P.O.E.M.) in 2010. In 2011 he pioneered world first robotic gastric ESD, followed by world first robotic colorectal ESD in 2020.

Prof. Kai Fung CHAN

Prof. Kai Fung CHAN’s research interests include medical miniature devices, micro-/nanorobotics, and translational medicine. His research interests are (1) Miniature medical devices for the in vivo diagnosis and treatment of gastrointestinal diseases; (2) Microrobotic sensing platforms for automated pathogen sensing; (3) Micro-/nanorobotics for minimally invasive endoluminal intervention; and (4) the corresponding translational research. His research on microrobotic platforms for biomedical applications was published in Science Robotics in 2021 and Advanced Materials in 2022. One of them was highlighted in Nature Spotlight and many local media. He has 7+year of experience in biomedical engineering research and preclinical studies.

Dr. Mengmeng SUN

Dr. Mengmeng SUN, the first author of the research paper has proved that science and fiction can merge. He says he got his inspiration for slimebot from the Venom character in the Spiderman movie. For the less fictional future, with the laboratory’s 10 years of experience on magnetic actuation technology, the team hope to deploy the slimebot in a robotic arm that can magnetically control it from outside the body. Precision with real time monitoring and safety are of the utmost importance if the robot is to be deployed in human body. Now, the team is working on pre-clinical trials. 

The findings have been published in Advanced Functional Materials:

M. M. Sun, C. Y. Tian, L. Y. Mao, X. H. Meng, X. J. Shen, B. Hao, X. Wang, H. Xie*, L. Zhang*, Reconfigurable Magnetic Slime Robot: Deformation, Adaptability, and MultifunctionAdvanced Functional Materials, Vol. 32, Issue 26, 2112508, 2022. [Link]