Put a gecko-inspired robot on the teachers’ heels: More lively lectures

Lizards like geckos and agamas have inspired scientists to develop a new robot-controlled camera that can make streamed lectures less dull.

By Birgitte Svennevig, 2/9/2022

Most students have tried it; to follow an online lecture with the teacher sitting or standing on the very same spot throughout the lecture. If the teacher would just walk around a bit!

– We as teachers don’t like it either, it’s boring to death. A lecture can become incredibly static when the teacher has to sit or stand in the same place throughout – but that is necessary when you want to record the lecture on video, says Jakob Christensen-Dalsgaard, associate professor at the Department of Biology.

The reason for this is that usually only a single camera on a tripod is set up, and then the teacher has to stay within the camera frame.

Where does the sound come from?

– Our idea was to see if we could change that, says Jakob Christensen-Dalsgaard.

In addition to teaching, he also studies animal hearing and has a special interest in the hearing of reptiles and birds, including how they orient themselves to sounds in the environment.

This expert insight has now led to the development of a small, simple robot with the potential to liven up online lectures.

– Like a lizard, our robot registers where the sound comes from and then turns itself towards the sound source – in this case the teacher. If the teacher moves, the robot will follow. We then put a camera on the robot, and thus the camera will always follow the talking teacher, who is now free to walk around, Jakob Christensen-Dalsgaard explains.

The central component of the robot is an electronic model of the ear, found in a number of lizards, including geckos, agamas and certain iguanas.

– Their mechanism for directional sound is very, very simple. It must be taken completely literally when I say that sound goes through one ear and out of the other, Jakob Christensen-Dalsgaard explains.

However, this makes their eardrum very directionally sensitive, and thus the animal becomes aware of where the sound is coming from. Unlike us humans and a lot of other animals, they don’t need to use computing power in the nervous system to calculate where the sound comes from.

Simple is good when you are a robot designer

– Their detection of sound direction is much simpler, and they spend less resources on it.

“Simple” and “small resource consumption” are sweet words to a robot scientist.

– Simple systems in a robot means that the robot does not need as many electronic chips, and they do not use as much computing power. It saves on energy consumption, so the battery can last longer, and electricity consumption will be lower, says Jakob Christensen-Dalsgaard.

Agamas at SDU

No one has yet succeeded in training lizards to participate in behavioral experiments – for example to test if they respond to sound. This is nevertheless the goal of Jakob Christensen-Dalsgaards research team, who is currently working with 10 agamas on campus.

The irony is that lizards like agamas apparently do not use their directional hearing in the same way that the robot does.

– An agama does not turn itself towards sound sources. Apparently sounds do not cause it to change its behavior. Also, they do not communicate with each other via sounds. So, you may ask yourself; what is the purpose of their sensitive ears? Our bid is that they use the sense of hearing to orient themselves to biologically interesting sounds, says Jakob Christensen-Dalsgaard.

He has studied agamas for many years, and his research group keeps xx of them for research use at SDU. Until now, the researchers have mapped the path of sound from the agama’s middle ear to the auditory nerve. The next step will be to examine the central nervous system of the agama; does it function along the same principles as humans when it comes to assessing whether the body should perform an action caused by sound?