New Soft Sensors - Evolving Robot Soft Skin

2023-12-18

Recently, a new type of intelligent, stretchable, and highly sensitive soft sensor has emerged, which is expected to become the new skin for robots. Its arrival has brought new changes to the appearance of robots and applications such as artificial limbs. Thisa new product jointly developed by Honda and the University of British Columbia, one of the earliest developers of humanoid robots.

When this type of sensor skin is applied to the surface of prosthetics or robot limbs, it can provide the robot with touch sensitivity and flexibility, allowing the machine to perform previously difficult tasks, such as easily picking up soft fruits. At the same time, due to the similar tactile characteristics of soft sensors to human skin, it helps to make the interaction between robots and humans safer and more realistic.

The University of British Columbia, abbreviated as UBC, is one of the leading institutions in robotics research in Europe. The UBC team collaborated with Frontier Robotics at Honda Research Institute to develop this technology. Honda has been innovating in the field of humanoid robots since the 1980s and has developed the famous ASIMO robot, as well as other assistive walking devices and the emerging Honda Avatar robot.

This sensor is made of silicone rubber, which is commonly used in movie special effects to make skin materials. Its unique design allows it to bend and wrinkle like human skin. Sensors use weak electric fields to perceive objects, even in the distance, just like touch screens. But unlike traditional touch screens, this type of sensor is very soft and can detect the force of an object entering and moving along its surface. This unique combination is necessary for robots to interact with humans.

This sensor uses the sum and difference of signals from four deformable capacitors to distinguish between simultaneously applied normal and shear forces. The crosstalk between shear force and normal force is less than 2.5%, and the crosstalk between shear axes is less than 10%. The sensitivity of normal stress and shear stress is 0.49 kPa and 0.31 kPa respectively, with a minimum displacement resolution of 40 μ M. In addition, the detection range of finger proximity can reach 15 millimeters.

One of the main authors of this study, Ryunosuke Ishizaki, Chief Engineer of Frontier, said, "UBC's Dr. Maden Laboratory has extensive expertise in the field of flexible sensors, and we are pleased to collaborate with them to develop this tactile sensor technology suitable for robots."

Researchers point out that the manufacturing of this new type of sensor is relatively simple, making it easy to expand to cover large areas and carry out large-scale production. Dr. Maden emphasized that the continuous development of sensors and intelligent technology has made robots more powerful and realistic, allowing people to collaborate and interact more with them.

However, the role of soft sensors goes far beyond that, Dr. Maden stated: "The perception points on human skin are 100 times more than our current technology, making it easier for robots to perform more precise tasks, such as lighting matches or sewing. As sensors become closer to the characteristics of human skin and can also detect temperature and damage, robots need to have a more intelligent understanding of which sensors to focus on and how to respond. The development of sensors and artificial intelligence needs to be promoted synchronously."

The UK Welding Institute will conduct comparative testing between handheld laser welding and arc wel