A robot being developed at Tel Aviv University "hears" electrical signals, thanks to a natural sensor: the ear of a dead locust.

So far, the call and response made possible by a locust-eared robot is a basic one. When a researcher claps, the locust's ear registers the sound and the robot moves forward. When a research claps twice, the robot moves backwards.

The demonstration, however, of combining robotic platforms and biological elements opens the door for an exciting set of new applications, according to Dr. Ben M. Maoz, a lead researcher on the project and a professor at the Iby and Aladar Fleischman Faculty of Engineering and the Sagol School of Neuroscience.

"You can imagine all kinds of tasks that today use animal sensors, that can be replaced by such robots. for example, like smelling drugs and explosives," Dr. Moaz told Tech Briefs.

The results of the study were published in the journal Sensors .

What the Locust-Ear-on-a-Chip Looks Like

A microfluidic chip connects to a custom designed suction electrode. The locust auditory nerve, housed inside of the chip, is pulled into the suction electrode prior to recording. The "ear-on-a-chip acts as a sensor and then responds to sounds.

In addition to the customized chip and suction electrode, the robotic platform includes a signal amplifier and a controller and signal processor system (CSPS).

The ear-on-a-chip keeps the ear alive by supplying oxygen and food to the organ, while allowing the electrical signals to be taken out of the locust's ear and amplified and transmitted to the robot.

Along with locust expert Prof. Amir Ayali (from the School of Zoology) and sound expert Prof. Yossi Yovel (from the Sagol School of Neuroscience), Dr. Maoz replaced the robot's electronic microphone with a dead insect's ear.

The ear detects signals from the environment, in this case vibrations in the air. The special chip then converts the insect input to that of the robot.

This kind of achievement — a replacement of technological systems with biological ones — enables better sensitivity and energy efficiency, according to Dr. Maoz.

"Biological systems expend negligible energy compared to electronic systems. They are miniature, and therefore also extremely economical and efficient," said Maoz in March .

In a Q&A with Tech Briefs below, Dr. Maoz describes the kind of future he envisions with technology that truly takes from nature.

Tech Briefs: What is the significance of this achievement?

Dr. Ben M. Maoz: The significance of this work is to show a proof of concept that we are able to integrate biological elements with robotic platforms. More specifically, we show that we can take the hearing system ,which can serve as an input for sound, to navigate a robot.

Here we show it for the sound system, but it opens many doors for more applications.

Tech Briefs: Do you intend to build a system that requires oxygen and food to be supplied? Or do you intend to try to mimic the locust’s ear and build a hardware equivalent?

Dr. Maoz: This matter is one of the main challenges of the project. We had to design a sophisticated device that gives constant oxygen and nurtrients to the locust ear to keep it alive.

Tech Briefs: Do you have to renew the nutrients? How often?

Dr. Maoz: Yes, fresh nutrients need to be given to the ear. We can either do it manually after 4-6 hours or with a perfusion system that we have, which can do it continuously.

Tech Briefs: What does this system look like?

Dr. Maoz: The device is a "microfluidic chip" that has special channels and holders which hold the ear close to the air, but also inside there is a special liquid which provides the necessary nutrients to the ear.

Tech Briefs: What inspired you to go with a locust?

Dr. Maoz: I was blessed to work with Prof. Yossi Yovel who is a sound expert and Prof. Amir Ayali who is a locust expert. So we decided to start with this, on top of the great hearing capabilities that the locust has.

the robot with a locust ear, being developed at Tel Aviv University
The robot, developed at Tel Aviv University

Tech Briefs: Is the locust application more of a demonstration? What can you do with a robot that has that kind of detector?

Dr. Maoz: Since the project was so ambitious, we wanted to start by integrating a sense that will be relatively "easy" to compare to electronic sensors (which, in this case, will be a microphone). Now, that we know that the concept is actually working, we are working on other sensing capabilities (such as smell) that are much more challenging to create with today's technology.

Tech Briefs: Do you envision a future where the technology is more biological, like “Smellicopters?” What are the advantages of going with more biological tech?

Dr. Maoz: Millions of years of evolution were able to create small, sensitive and efficient sensors that we are not able to mimic with todays' technology. Therefore, we would like to use and integrate these amazing capabilities of sensing with robotic platforms.

Tech Briefs: What’s the next test? Is it about refining the locust application, or trying out new ideas with kinds of organisms?

Dr. Maoz: We are currently thinking about integrating "the best of all worlds," which can be array of sensors from different insects. This can include either working with one sense of multiple organisms, or multiple sensors from different organisms. After publishing the paper, many people contacted us with crazy and interesting ideas and applications that we are currently looking on.

Do you have any ideas? What do you think of a more biological take on tech? Share your questions and comments below.