Very often I have seen that students who do no5 necessarily fare well in exams or the like, nevertheless blossom when you give them hands on projects to do or ideas to work on. In fact, innovative pedagogy involves bringing out the best in the student- a good teacher should be able to bring out the best in the student and be understanding enough to see what makes the student tick. Here's an example of how a simple undergrad project blossomed into a world class work leading to a publication in Nature Electronics, one of the world's best scientific journals.

Students at Amrita, who do remarkably well in Dr Balakrishnan’s ‘Electronic Materials’ course, or similar courses, at times get an opportunity to work in Dr Das state-of-art nano-electronics labs, as part of Amrita’s wide spread Student Exchange Program.

Several such students who have gone there have published in Nature and leading journals.

One such outstanding research student was Darsith Jayachandran, from Mechanical Engineering, Amrita's Amritapuri Campus, who went to Dr Das’s lab.

What started as an undergraduate project, continued to be Darsith’s Ph.D. work in Dr Das’ lab where research is going on, on biomimetic devices. Darsith is pursuing his Doctorate in Engineering Science and Mechanics, focusing on low-dimensional nano-electronics, biomimetics and artificial vision.

The project involved developing a collision detector. Collision detection is a critical element in fields like autonomous vehicles and robotics where many models inspired from insect vision are developed for the same. A neuron called the lobula giant

movement detector (LGMD), found in locusts, is well-known for detecting objects on direct collision course with the insect. Different collision avoidance models have been developed, but none are as efficient as this neuron in terms of energy

and area efficiency. So, we developed a nanoscale collision detector that consists of molybdenum disulfide photodetector stacked on top of a non-volatile and programmable floating-gate memory architecture.

This unique device structure helps in mimicking the LGMD like escape response to an incoming object. It consumes a small amount of energy (in the range of nanojoules) and has a small device footprint (~1 µm × 5 µm).

This is a great example of Biomimetic research -

The researcher’s report in the (Aug. 24) issue of Nature Electronics that this "is a leap forward towards the development of smart, low-cost, task-specific, energy efficient and miniaturized collision-avoidance systems."

According to the researchers, locusts move at two to three miles per hour and make directional changes in hundreds of milliseconds. The decision to move employs non-linear mathematics and a minuscule energy expenditure.

This quick reaction and modest energy use is attractive for mechanized collision detectors. Current detectors for autonomous automobiles are very large and very heavy.

The researchers' collision detector responds in two seconds. Also, rather than be a jack-of-all trades detector, the molybdenum sulfide-based sensor is task specific, but because it is so small and uses so little energy, that is acceptable,

according to the researchers.

The photodetector causes an increase in device current in response to an oncoming object, the excitatory signal, while the underlying programmable memory stack always causes a decrease in the current, the inhibitory signal.

When an object approaches, the excitatory signal is added to the inhibitory stimuli, causing a non-monotonic change in the device current, mimicking the escape response of the LGMD neuron found in locusts.

Also working on this project from Penn State are

- Amritanand Sebastian, who is also an Amrita alumnus, now a graduate student in Engineering Science and Mechanics;

- Tanushree H. Choudhury, Assistant Research Professor, 2D Crystal Consortium – Materials Innovation Platform; and

- Joan M. Redwing, Professor of Materials Science and Engineering, Chemistry Engineering and Electrical Engineering, and Associate Director of the Materials Research Institute.

This is a great example of a successful collaboration between Amrita and Penn State.