Soft robots have gotten a lot of press lately because of their flexibility and safety. The fluidic systems in these robots, on the other hand, continue to employ pumps that are huge, heavy, and loud. Researchers have developed a fluid pump that is simple, lightweight, quiet, and capable of self-sensing actuation, with potential applications in wearable technology and touch display displays.
The name “robot” conjures up thoughts of tough mechanical bodies that are impenetrable to assault. Robots, on the other hand, are seldom required to defend against hostile assaults in contemporary life. Instead, they have to deal with more basic activities like handling delicate products and communicating with others. Regrettably, traditional robots fail miserably at such apparently basic jobs. Furthermore, they’re bulky and often loud.
“Soft” robots have the upper hand in this situation. Soft robots absorb shocks better, adapt better to their surroundings, and are safer than traditional robots because they are made of “elastomers” (materials with high viscosity and elasticity). A wide variety of applications, including medicine and surgery, manipulation, and wearable technology, have resulted as a result of this. Many of these soft robots, however, depend on fluidic systems, which still rely on mechanical pumps (motors and bearings). As a consequence, they remain cumbersome and loud.
Chemical processes may be used to drive pumps as a solution to this issue. However, although such systems are certainly light and silent, they do not work as well as traditional pumps. Is there a way to avoid this compromise? The answer, it turns out, is yes. Prof. Shingo Maeda led a team of researchers from Japan’s Shibaura Institute of Technology (SIT) to propose a “electrohydrodynamic” (EHD) pump that employs electrochemical processes to drive pumps. The EHD pumps offer all of the benefits of chemical reaction-driven pumps with none of the drawbacks.
Prof. Maeda, Yu Kawajima, Dr. Yuhei Yamada (all from the Department of Engineering Science and Mechanics, SIT) and Associate Professor Hiroki Shigemune (Department of Electrical Engineering, SIT) have now designed a “self-sensing” EHD pump that uses an electrochemical dual transducer (ECDT) to sense fluid flow, which then activates electrochemical reactions and increases current in a recent study. “Recently, self-sensing technology has gotten a lot of press for compacting soft robots. Sensors in soft robots improve their multifunctionality, but they typically result in complicated wiring and bloating. Self-sensing actuation technology may help overcome this problem and enable soft robots to be miniaturized “Prof. Maeda adds. On January 7, 2022, this work was made accessible online, and on January 19, 2022, it was published in Volume 14 Issue 2 of the journal ACS Applied Materials & Interfaces.
The ECDT pump was based on the EHD pump that the team had previously built. The pump was made out of a symmetrical set of planar electrodes that enabled the flow direction to be easily controlled by adjusting the voltage. Furthermore, due to the identical intensity of the electric field on both sides, the configuration allowed for an obstruction-free flow in both directions.
The researchers assessed sensing performance in terms of flow range, rate, sensitivity, responsiveness, and relaxation durations, as well as using mathematical modeling to better understand the sensing process. “Without bloating or complexity, the ECDT may be simply incorporated into a fluidic system,” explains Yu Kuwajima, a PhD student at the Smart Materials Laboratory (SIT) and the study’s lead author. The researchers also put it to the test by using it to operate a suction cup that could detect, grip, and release items.
“The ECDT has the benefit of not requiring any specific equipment or complicated procedures to manufacture. Furthermore, it is compact, light, and has a broad range of sensitivity “Prof. Maeda agrees.
The ECDT, on the other hand, is about more than soft robot shrinking. It’s a step toward a future in which people and robots not only coexist, but also interact in a fluid and natural manner. Certainly an interesting opportunity for entertainment!