Robots can sense!

‍

Imagine that if there are robots that have senses like what humans possess, what will happen? To draw an example for that, let’s get back to the old days when the miners took caged canaries in the coal mine. This kind of bird is able to sense dangerous chemicals such as carbon monoxide. However, the canaries would then die after facing those chemicals, so the miners could recognize it as a warning sign.
‍

Thus, if we can invent the robots or machines that own the ability of sensing, there is no need of sacrifice; all of us would be out of danger.
Here, researchers at Carnegie Mellon University have now developed soft robots that can sense and respond to chemical signals. 
‍

‍

The combination between biology, engineering and robotics

“The ones that always stuck out to me were the octopus and cuttlefish and how they can interact with their environment and camouflage themselves to hide from predators. The fact that these organisms have cells that can sense and respond to their surrounding environment and basically act as soft machines was really exciting to us,” said Kyle Justus, an alumnus of the mechanical engineering doctoral program.

Justus and his team intended to combine synthetic biology, mechanical engineering, and robotics in order to create their ideal robot inspired by incredible organisms with their great sensing ability. This project was supervised by Carmel Majidi, an associate professor of mechanical engineering; and Philip LeDuc, a professor of mechanical engineering. 
Furthermore, to increase proficiency in synthetic biology, Carnegie Mellon researchers have collaborated with Cheemeng Tan, an associate professor of biomedical engineering at the University of California, Davis.

Turning a biological signals into an electornic signals
‍

‍Researchers have put “engineered bacteria cells”  into a flexible gripper on the robot’s arm. Theses cells are able to respond to IPTG, a chemical that can unlock an engineered genetic circuit. The important part is that once IPTG unlocks that circuit, the engineered bacteria cells will release a “fluorescents protein” which can be a signal. 

But the question is that how we can train the robot to understand that signal. LeDuc said, “That was one of the hardest things we had to accomplish: how do you turn a biological signal into a signal that a robot can process?”

‍

“Turning a biological signal into an electronic signal is the answer.” Researchers created a flexible light-emitting diode (LED) circuit, which its function is to detect and arouse the fluorescent protein. After the LED circuit detect that kind of protein, it will send an electronic signal to the gripper’s central processing unit. Consequently, their robot arm can understand whenever it senses IPTG.

‍

Justus said, “What we have in most living systems are largely soft organism-level architectures that rely on the smaller subcomponents—cellular systems—to sense and respond to different cues and maintain life. Obviously, we’re doing it in non-living systems, but we’re using living subcomponents and trying to increase device capabilities by relying on that existing biological hardware.”

‍

This technology—the gripper with the sensing ability—was tested to sense chemicals in liquid media and hydrogels (polymer networks that can retain large of water), and the results indicated that the gripper could sense the IPTG in the laboratory water bath, and decide to deploy the object into the bath after it could not find IPTG on the object.

Retrieved from: https://engineering.cmu.edu/news-events/news/2019/09/12-leduc-majidi-soft-robotics.html