Conventional approaches to cyborg insect preparation involve cutting antennae or cerci (sensory appendages) to implant electrodes, or using adhesives (like poly ionic liquid gels) to attach noninvasive films. "The methods have flaws: (1) Invasive implantation irreparably damages sensory organs, reducing the insect's ability to detect obstacles and navigate; (2) Adhesive-based films degrade over time, cause exoskeleton harm during removal, and require skillful application—extending preparation time and limiting reuse; (3)Ethically, cutting appendages violates the "3Rs" framework (Replacement, Reduction, Refinement) for humane animal research, raising concerns about animal welfare." explained study author Hirotaka Sato.
Researcher designed two key wearable components—headgear for antenna stimulation and abdominal buckles for acceleration control—that attach securely without adhesives or injury, preserving the insect's natural functions. Antennae are critical for insects to sense obstacles, odors, and airflow. The researchers targeted the scape—the sturdy, base segment of the antenna—to avoid disrupting the more sensitive pedicel and flagellum (which house sensory receptors). The headgear features: (1) C-shaped elastic connectors: These grip the scape tightly, transmitting electrical signals without penetration. The elastic material expands temporarily during attachment, ensuring a snug fit; (2) Triangular hook mechanism: Three hooks (one top, two bottom) anchor the headgear to the cockroach's hard head capsule, avoiding sensitive areas like compound eyes and mouthparts. This design lets the insect eat normally and keeps the device stable during movement. Instead of implanting electrodes into small, mobile cerci, the team focused on the second and sixth abdominal segments—rigid, stable areas with overlapping exoskeletons. The abdominal buckle includes: (1) U-shaped clamp: Fits the natural contour of the abdomen, securing the device vertically; (2) Gripping hooks: Clamp onto the edges of abdominal terga (exoskeletal plates), preventing slipping; (3) Overlapping structure integration: Leverages the insect's natural segment overlap to enhance stability, allowing the abdomen to flex and extend freely during locomotion.
"To create these intricate, functional devices, we used digital light processing (DLP)-based multimaterial 3D printing and selective electroless copper plating—technologies that enable precise control over conductive and nonconductive regions." emphasized the authors. The researchers tested their devices on Madagascar hissing cockroaches (Gromphadorhina portentosa)—a common cyborg model due to its 15g load-bearing capacity. Key results include stable neural responses, precise motion control, accurate S-Path navigation, and superior obstacle negotiation.
"The noninvasive design preserves the insect's natural sensory capabilities, which is game-changing for real-world use," said Hirotaka Sato, corresponding author and professor at NTU's School of Mechanical and Aerospace Engineering. "This work moves cyborg insects from lab demonstrations to scalable, practical tools in robotics and biohybrid systems."
Authors of the paper include Phuoc Thanh Tran-Ngoc, Kewei Song, Thu Ha Tran, Kazuki Kai, Qifeng Lin, and Hirotaka Sato.
This work was supported by the KLASS Engineering & Solutions Pte. Ltd. (RCA_Klass_REQ0374521) and NTUitive Pte. Ltd. (NGF-2022-11-020).
The paper, "Ergonomic Insect Headgear and Abdominal Buckle with Surface Stimulators Manufactured via Multimaterial 3D Printing: Snap-and-Secure Installation of Noninvasive Sensory Stimulators for Cyborg Insects" was published in the journal Cyborg and Bionic Systems on Sep 22, 2025, at DOI: 10.34133/cbsystems.0406.
