Innovative Rescue Technology Using Cyborg Insects
In the wake of natural disasters, the deployment of small robots and drones has become commonplace for searching for individuals trapped beneath rubble. However, a significant challenge arises when the gaps are too narrow, rendering them inaccessible to both humans and the currently available robotic devices. In this context, cyborg insects—living insects augmented with electronic components and remotely controlled—have garnered attention as an agile and energy-efficient tool for search operations. Traditionally, these systems have focused primarily on locating victims, with limited capabilities for direct assistance.
To address this limitation, a research team from the University of Queensland (UQ) and the University of New South Wales (UNSW) has developed a novel system named Paraborg. This initiative employs the rhinoceros cockroach (Macropanesthia rhinoceros), native to northern Queensland, not only for exploration but also to provide first aid to disaster victims. “For the past two decades, cyborg insects have been designed for search and exploration missions. We aimed to take it a step further,” explains Dr. Tan-Vo Doan, a researcher in biorobotics at UQ.
Remote Control and Automation Mechanisms
The rhinoceros cockroach is a relatively large species, reaching lengths of 84 to 87 mm and weighing between 34 and 40 g. Leveraging this substantial size, the research team created two distinct types of Paraborg, each with specific functions: one fitted with a camera to monitor the condition of victims, and another equipped with an automatic injection mechanism (AIM) for administering medication.
By applying electrical stimuli to electrodes implanted in the cockroach’s antennas and tail plates, researchers can control the insect’s direction and speed remotely. Stimulating the left antenna causes the cockroach to turn right, while stimulating the right antenna results in a left turn; furthermore, increasing the stimulation frequency between 10 to 50 Hz amplifies the turning angle. By stimulating both tail plates, the cockroach’s speed can be increased. This mechanism allows for precise control of basic movements by combining these two types of stimuli.
The AIM is a compact device that uses spring force to activate a syringe, injecting liquid into a target by pushing the syringe’s rubber stopper (piston) using carbon dioxide pressure generated by a reaction between citric acid and potassium bicarbonate. The peak pressure from this chemical reaction reaches approximately 470 kPa within an average of 4.5 seconds. Reportedly, the success rate for AIM injections alone was 74% in experiments using silicone as a target and 90% in tests with pig skin. In both scenarios, the injection needle penetrated to a depth of around 5.5 mm.
Successful Field Trials and Collaborative Insect Operations
It is noteworthy that the maximum weight a cockroach can carry is estimated to be around 50 g, equivalent to 1.5 times its body weight. Observations indicated that cockroaches equipped with the AIM increased their total height by approximately 15 mm and gained about 17 g in weight, yet this did not significantly hinder their normal locomotion. In a series of experiments, the team successfully controlled a cockroach to navigate three checkpoints before administering an injection to a simulated target. When the insect began to respond less to electrical stimuli during its journey, researchers adjusted the frequency by increasing it by 10 Hz or stimulated the opposite antenna to redirect its path. With these modifications, the cockroach managed to reach all checkpoints in each trial.
The experimental results revealed that the success rate for injections conducted within 150 mm of the target peaked at approximately 95%. Conversely, the overall success rate for the entire sequence of operations, from departure to injection completion, stood at 72%. “It is essential to maintain sufficient stability to navigate towards the target, accurately determine its position, and execute the injection,” remarks Hai Nyan Le, a doctoral student, highlighting the engineering challenges involved.
Harnessing Nature’s Strengths for Rescue Missions
In addition to developing a climbing cyborg beetle, the research team asserts that the larger size of cockroaches makes them more suitable for specialised rescue tasks. “Instead of creating a single robot that fits all uses, we leverage the innate strengths of different insects and can adapt the equipment according to the mission,” explains Võ Đăng. It is important to note that during the implantation of electrodes and microchips, anaesthesia is administered to the cockroaches, and they continue to live normally after the devices are removed. A representative from the New South Wales Fire and Rescue Department has also indicated that this technology could represent a novel means of extending the capabilities of rescue teams.
Nonetheless, the experiments conducted did not replicate the complex environmental conditions found in actual disaster sites, such as debris, uneven terrain, and narrow passages. Additionally, there is potential to adopt a safer injection method, such as a short-range technique where the device contacts the target before being activated by a gentler spring mechanism, or a microneedle patch that administers medication simply by pressing it against the skin.
Future Prospects for Cyborg Insect Rescue Teams
The long-term vision of the research team involves a framework in which individuals equipped with cameras and environmental sensors, along with others carrying medical devices, collaborate in groups, each assuming a specific role. Vaux Doan is optimistic that, with the necessary resources to accelerate research and field testing, a rescue team composed of cyborg insects operating in real disaster areas could become a reality within the next 5 to 10 years.