In context
In early 2024, the robotics field was actively exploring soft, bio-inspired solutions for medical diagnostics, particularly for gastrointestinal examinations. Traditional endoscopy is invasive and uncomfortable, while capsule endoscopes lack active control. This research from Jiangnan University and Shanghai University, published in the Chinese journal Robot, addressed the need for a patient-friendly, nondestructive method to inspect the intestines.
What was reported
Researchers designed a soft robot mimicking a leech's peristaltic crawling. It comprises two adsorption actuators acting as front and rear suckers, and a self-binding multi-chamber actuator serving as the body for extension and contraction. The adsorption actuators feature a novel double-layer structure: a stiffer outer chamber (Dragon Skin 10) and a softer inner chamber (Ecoflex 00-30), improving airtightness and preventing collapse under negative pressure.
Experiments demonstrated a maximum adsorption force of 3.05 N per actuator, with a pressure differential of 7.19 kPa—below the 10 kPa threshold that could harm intestinal tissue. The robot achieved a crawling speed of up to 5 mm/s on flat surfaces, slopes, and in an intestine-like environment. The body actuator's axial extension was validated through finite element simulation and physical tests, showing controllable displacement up to 80 kPa input pressure.
The double-layer design also isolates internal air chambers from the external environment, preventing contamination of the intestinal microbiome. The robot is fabricated from silicone rubbers (Ecoflex 00-30, Ecoflex 00-50, Dragon Skin 10) with Young's moduli matching human tissue, ensuring safe interaction.
Why it mattered
This work offered a promising alternative to conventional endoscopy, potentially enabling painless intestinal examinations, targeted drug delivery, and biopsy sampling. The design's reduced contact area and lower force on mucosal surfaces could minimize tissue damage, addressing a critical barrier to patient compliance and advancing soft robotics for medical applications.
This work is expected to provide a non-destructive and patient-friendly approach for the application in the examination and treatment of intestinal diseases.
Source: 《机器人》期刊 (robot.sia.cn) · Published 2024-03-27 · “仿水蛭蠕动爬行软体机器人设计”