AsianScientist (Jun. 14, 2018) – Scientists in Hong Kong have developed a material that can alter its volume in response to light, electricity and other stimuli, paving the way for wirelessly-controlled robots. They reported their findings in Science Robotics.
To develop micro and biomimetic robots, artificial muscles and medical devices, scientists have turned to actuating materials—materials that can reversibly change their volume under various stimuli—to replace traditional bulky and heavy actuators including motors and pneumatic actuators.
Among various stimuli, light-induced actuating materials are highly desirable because they enable wireless operation of robots. However, very few light driven materials are available in the past, and their material and production costs are high, which hinder their development in actual applications.
In this study, a mechanical engineering team led by Professor Alfonso Ngan Hing-wan at the University of Hong Kong (HKU) introduced a novel actuating material—nickel hydroxide-oxyhydroxide—that can be powered by visible light, electricity and other stimuli. The material actuation can be instantaneously triggered by visible light to produce a fast deformation and exert a force equivalent to 3,000 times of its own weight.
In addition to its visible light actuation properties, this novel material system can also be actuated by electricity, allowing it to be integrated into existing well-developed robotics technology. It is also responsive to heat and humidity changes, which means that they could be applied in autonomous machines that harness tiny energy changes in the environment to generate power.
The material cost of a typical actuator is as low as HK$4 (~US$0.50) per cm2 and can be easily fabricated within three hours using the simple process of electrodeposition. These properties make it possible to manufacture it at scale for industrial purposes.
The article can be found at: Kwan et al. (2018) Light-stimulated Actuators Based on Nickel Hydroxide-oxyhydroxide.
Source: University of Hong Kong; Photo: Shutterstock.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.