Soft robots that mimic the movements and behaviors of animals have been attracting a lot of attention in recent years, as they can offer advantages over traditional rigid robots, such as flexibility, adaptability, and safety. One of the most fascinating examples of soft robots is the inchworm-inspired robot, which can crawl on various surfaces by alternately contracting and extending its body segments, just like a real inchworm.
Researchers at Nagoya University and Tokyo Institute of Technology have recently developed a new inchworm-inspired robot that can carry loads of more than 100 g at a speed of approximately 9 mm per second. This is a significant improvement over the previous models of inchworm-inspired robots, which had lower speed and load capacity. The new robot, introduced in the journal Biomimetic Intelligence and Robotics, could potentially be used to transport objects and place them in precise locations, such as in automated logistics applications or in the handling of delicate materials.
The new robot consists of three body segments, each equipped with a McKibben artificial muscle, which is a type of pneumatic actuator that can contract and expand by changing the air pressure inside a rubber tube surrounded by braided fibers. By controlling the activation sequence and timing of the three muscles, the robot can generate a “Ω”-shaped movement, similar to that of an inchworm, and move forward or backward.
The researchers tested the performance of the robot by measuring its speed and load capacity under different conditions, such as the number of activated body segments, the size and material of the objects carried, the air pressure supply, and the command execution rate. They found that the robot could achieve the highest speed (8.54 mm/s) and load capacity (113.4 g) when all three body segments were activated, the object was small and light, the air pressure was high, and the command execution rate was low. They also observed that the robot could adapt to different surface textures, such as smooth, rough, or sticky, by changing its movement strategy.
The table below summarizes the main parameters and results of the robot’s performance.
| Parameter | Description | Range | Optimal value |
|---|---|---|---|
| Number of activated body segments | The number of body segments that contract and extend during movement | 1, 2, or 3 | 3 |
| Size and material of the object | The length, width, height, and weight of the object carried by the robot | Length: 10-50 mm <br> Width: 10-50 mm <br> Height: 5-20 mm <br> Weight: 1.2-113.4 g | Small and light |
| Air pressure supply | The pressure of the compressed air that inflates and deflates the McKibben muscles | 0.1-0.4 MPa | 0.4 MPa |
| Command execution rate | The frequency of sending commands to the robot to activate the muscles | 0.5-2 Hz | 0.5 Hz |
| Speed | The distance traveled by the robot per unit time | 0.67-8.54 mm/s | 8.54 mm/s |
| Load capacity | The maximum weight of the object that the robot can carry without losing its movement ability | 1.2-113.4 g | 113.4 g |
The researchers believe that their inchworm-inspired robot could be further improved by using deep learning techniques and other computational models, which could enable the robot to autonomously adjust its movement strategy according to the environmental conditions and the object characteristics. This could enhance the robot’s performance and efficiency in real-world scenarios, where the robot may encounter various challenges and uncertainties.
The inchworm-inspired robot is an example of how biomimicry, the imitation of nature’s designs and principles, can inspire innovative solutions for engineering problems. By studying and replicating the simple yet effective mechanisms of biological organisms, such as the inchworm, researchers can create soft robots that can perform complex tasks with minimal energy and material consumption.
