I’m Bhavini Jeloka, a second-year undergraduate in the department of mechanical engineering. I’ve been pursuing a minor in the systems and controls department and I’m also a member of the Guidance, Navigation and Control (GNC) Subsystem in the Student Satellite Program (SSP) of IIT Bombay. Apart from academics, I love to read and write. I’ve been trying to read as many books as I can, and write as much as I can in this lockdown period because my pace slows down dramatically when the semester is inflow.
I’m currently involved in a research-based internship under Prof. DHS Maithripala, from the Univ. of Peradeniya, Sri Lanka (SL), where I am working on the optimal control for a quadcopter (as of now, using geometric mechanics). It is an extension of my project in the SysCon Department, under Prof. Ravi Banavar from our own institute.
Initially, I was under the mechanical subsystem in the SSP. While I was working under the thermals subsystem, I noticed how difficult yet interesting the GNC (then, ADCS – Attitude Determination and Controls Subsystem) seemed to me. They were developing a closed-loop framework for controlling a satellite – something that was nothing more than a lot of heavy and complex words to me. However, when I started reading about dynamics and other concepts for my ITSP, I realized that all the daunting jargon was based on simple principles of physics. My first course in my syscon minor introduced me to the mathematical representations of all these physical phenomena. Alongside this, I was also a part of a short workshop on geometric mechanics which was taken by the same professor from SL. This appealed to my interests even further. He had explained, amongst many other things, the PID control. I had some idea about it through various sessions in insti, but this was the first time I had a proper background understanding of the topic. It made me consider the option of exploring the topic further. Apart from controls, I had found the course on fluid mechanics in my third semester, extremely interesting and I thought that this was another engrossing field too – and so the process of seeking a research-based internship began!
Once I had narrowed down the topics mentioned above, I took help from some of my seniors and gathered some insights on the process of writing applications, or by institute lingo, ‘apping’. In my winter holidays, I made a database of all the professors I wanted to contact. Most of them were based in foreign universities, but I had also added ISRO and DRDO to the list. However, the process of apping was highly random – you could not foresee the probability of receiving a reply. It was disheartening to the point where even if I got a reply which rejected me, I was happy to have at least heard back from them. The reasons for rejection were always the same – they weren’t looking for undergraduate interns, only PhDs. In retrospection, seeing my lack of depth in the subjects (because I was only in my second year), I could very well understand their reasons for rejection. Nevertheless, I continued this unmethodical process – hoping to hit the bull’s eye. However, it was only followed by more and more frustration. As winter was coming to an end, and my chances for securing an intern were null, I was advised to approach the professor I was doing my project under, and ask him for help. He readily agreed to help me out and said that he would do whatever was in his reach for the same. This led to the aforementioned internship.
The professor from SL, has worked on several autonomous systems and is also keenly interested in the field of geometric mechanics. He has great experience in the field of drones and quadcopters as well – the main topic of my work. Until now, I’ve read a lot of theory on various topics in controls – Lyapunov stability, classical control, state-space representation and so on. I’ve also explored topics like rotation matrices, Lagrangian mechanics, variational calculus (one of the most mind-boggling/blowing concepts), and dynamics of rigid bodies. Barring theory, I’ve also tried my hands on animation based simulations of rigid body systems using Python.
All that I wrote above was ideally going to happen in Sri Lanka. However, the pandemic struck and just like a lot of other things, my work had to be done from home. I had booked tickets for the trip and the day my flight was due, I became dispirited because I was looking forward to visiting the lab. Nonetheless, I got back my enthusiasm and persisted.
The area I was working in was new to me in many ways and I found it extremely captivating. I had been reading a few papers on the modeling of quadcopters initially, so that I could understand their dynamics properly and apply the control laws. It was quite new to me and I was amazed by the mix of simplicity and complexity. I had read a lot of theory but all this was put to test when I had to solve an entire tutorial like sheet on the concepts. It took me a lot of time to consolidate the concepts and implement them in simulations. Luckily, the communication from both sides was prompt and both the professors were really helpful in clearing whatever doubts I had. I had frequent meetings to discuss my tasks and clear my confusions in any topic. A lot of times I hit roadblocks because some topics were really tricky and had to be read with the utmost patience. Most of my roadblocks were associated with my code not running. I had to learn how to make simple figures and about the animation function under python’s matplotlib library. This was so that I could visualise the motion of rigid bodies according to their equations. Since my work was in 3D, and also involved the equations of motion, I faced a lot of hardships in searching for help on Google. Traditionally, MATLAB was used for such simulations, however I was told that a lot of research work is being shifted to python and it would give me an edge if I developed the skill. So fighting all the frustration and bugs in my code, I was able to perform my first simulation. I uploaded it on Github and although it wouldn’t seem like much effort to an outsider, it was a huge milestone for me. For now, I could apply 3D modeling, animation, and simulation to just about anything!
To talk about the ‘process of research’ – it was similar to what I was expecting. However, it did involve a lot more patience than what I anticipated. Like the general saying, it’s not something that happens overnight! It requires a thorough understanding of topics and the ability to link those topics together. It’s not an easy road and often you lose sight of the purpose but it’s important to know that you’re a part of something big. Even for the small victory of my code running, I looked back and not once did I think that those three weeks went in vain. I came out with a new skill and now I know a little bit more. For me, that’s what made it worth my efforts. I don’t know what the future holds, but for me, grad school is certainly a possibility!