The prep talk for PhDs

Since you are reading it, I assume you are about to start your PhD program in my group or elsewhere. Or at least you are genuinely interested in applying for a PhD program. I still vividly remember my excitement on my first day as a PhD student. My advisor welcomed me and gave me a tour of the lab, introduced me to my labmates and, the most exciting part, handed me a key of the lab. If you are joining my team, unfortunately, I don’t have any lab keys for you. We use smart cards and PINs for access. But even without a physical key, I assure you that your PhD program is still as exciting. It is likely one of the most significant commitments you’ve ever made. And hopefully it will become one of the key cornerstones for your future careers and personal development. So, I think it is the best to lay out some major points at this stage to ensure that we are on the same page before starting this exciting and important journey. Here are some things that I would like to share with you as the “prep talk”.


I have to first point out an unpleasant fact of doing research: Things don’t work in most cases. The word “research” literally means “search again”. And that definition summarizes it well. We as researchers are people who keep searching. Failure is unavoidable. Actually, no, I should say failure is ubiquitous, while success is rare. It does not matter much how smart you are. As long as the subject is research-worthy, you are doomed to fail, again and again. If you persist, you may succeed at last.

Be prepared. Don’t be scared by the challenges, the frustrations, or the deadends. Try to accept them with an open mind, and recognize that they are the things that help you grow. I’m not saying that they are good and you should seek suffering. Accept how the project progresses, fast or slow, celebrate achievements and learn from setbacks. In a word, enjoy the journey.

When you are depressed by a seemingly never-ending frustrations, relax and take a deep breath. We’ve all been there. Take a day off, watch a movie, play some sports. Get it out of your mind before you press on. Don’t treat failure as a waste of time or an end. It is a stair up to reach success, as long as you don’t give up.

You are at the driver’s seat

One awakening moment in my PhD program is when I recognized that it is me who takes full responsible for my research, not my advisor or anyone else. Now I’ve sat at both sides of the table, I can tell you upfront that it is you who is sitting at the driver’s seat. It is you who works on a cutting-edge project full time. No one could know it better than you. No advisor can plan every step for you and offer a correct answer whenever you get stuck. Research is not learning a course, no one knows the correct answer. It is up to you to find, or even make, a path to pass through a maze. And break its wall sometimes when necessary.

As your advisor, it is my job to guide you by offering seasoned comments and suggestions and help you come up with a good enough strategy to address challenges. Maybe I’ve read a paper years ago which studied this problem and here is how they did it. Maybe I’ve already tried one of the options and it didn’t work and here is why.

It is also my duty to train you as an independent researcher with a solid foundation and a sound methodology. This is how we do this kind of experiments. This is how we run this kind of simulations. This is how we write academic articles.

And of course, it is my responsibility to apply for grants and keep the lab alive. You see, I have many duties to fulfill. But being your “cheat sheet” in research is not one of them. I cannot be and I also don’t want to be. Imagine your PhD training as learning to drive. You learn nothing if you don’t touch the steering wheel.

Work-life balance

I admit it sounds unconvincing to say that you should try to maintain a work-life balance, when academia is what it is right now. But I have an argument. Research is creative work. Your brain needs lots of fresh air to come up with interesting ideas. Take good rest, exercise, go outside, and entertain yourself. All these “slacking” things will help you maintain an optimal productivity in your time of actually doing research.

But you also cannot “slack” too much. Research won’t go anywhere without hardworking. So, a balance is important. When you are busy with catching a deadline, of course you can work extra hours for one day or two. But don’t make it a routine to over-work everyday. It is not productive, and it creates an illusion that makes you (falsely) feel that you’ve tried your best. That feeling is toxic.


I am well aware of the so-called “paper inflation”. People publish more paper on higher ranking journals year over year. I am also well aware of the fact that many (let’s be honest, it is actually “most”) universities evaluate candidates for post-doc or faculty positions primarily based on the publication record. But no, I am not in favor of prioritizing publication over everything else. When you publish, it should be something genuinely novel with clear contribution to the field. When you publish, we should both feel confident of the correctness and repeatability of the reported results. When you publish, each and every author should have contributed intellectually to this work.

Unless the university’s policy requires it, I do not pose any specific requirement on how many articles you should publish to graduate. But I do encourage you to share your work with others, by publications, presentations, or other communication channels. Exchanging ideas with your peers is magical. And communication in a professional way is an essential survival skill for a researcher.


There are some other points I think you should also be aware of. One is that research outcome often needs some luck. The curve of reward versus work is highly nonlinear. Be patient and be ready. Two is that academia is a trust system. What you do now will follow you for your whole academic life. So academic integrity is a baseline that you should never cross. On the bright side, what you achieve in this lab will also follow you when you graduate and become your permanent asset.

To summarize, doing PhD is hard, but also interesting. And nowadays doing a PhD is no longer bound with a career in academia. Many students go directly to the industry after graduation. So it will be helpful if you start to think about your future career plan early and try to adjust your PhD plan accordingly. After all, I hope this journey is rewarding for both of us. And good luck!


My thoughts on the motivation for small-scale robotics

Small-scale robotics, or more often referred to as Microrobotics, has become a hot research topic in the past ten years or so. Back in 2014, when I first started my PhD, I remember it was a relatively niche research field, and we joked about that probably a single classroom could accommodate all relevant researchers in the whole world. There is no denying that we all hoped this field would grow bigger. But I think it is safe to say that its growth has surpassed our expectation. As a researcher in this field, I want to reflect on what has fueled its exponential growth and what has motivated more and more people to join us.


Microrobotics is not the best name for this field. A better one is Small-scale Robotics. People use Microrobotics to vaguely refer to any robotic devices that are dramatically smaller than conventional robots, which are mostly at centimeter and meter size scale. But within this field, we use Microrobots more specifically, referring to the ones with a characteristic length between one and a hundred microns. Correspondingly, the larger ones with a characteristic length at millimeter are termed as Millirobots. And the smaller ones with a characteristic length from one to a hundred nanometers are called Nanorobots. When we are amazed by a millirobot that is 1000 times smaller than a conventional meter-scale robot, a microbot is 1000 times smaller than a millirobot, and a nanorobot is 1000 times even smaller. The differences between these three categories of small-scale robots are huge. Simply grouping them together and referring to everything as microrobots is not the best idea, because it implicitly conceals the distinctive challenges, methodologies, and applications associated with each of them.

Fantastic Voyage

With the definition clarified, we can now examinate the motivation. It is almost mandatory to mention a 1966 American movie Fantastic Voyage whenever people talk about the motivations for small-scale robotics. OK, we’ve also mentioned it. Mission completed. Well, joking aside, that movie is half a century ago and it is not the only movie (we don’t mention relevant novels here for conciseness) that tells a story about downscaling people. Admittedly, it is probably the one with the most specific application of such downscaling to address a fictitious medical need. The basic idea is simple, there are some regions inside human body that conventional medical approaches cannot reach, or it is too dangerous to reach. If only we were able to downscale doctors and put them into the patient’s body, into the heart or the brain for example, to diagnose and treat the disease locally, maybe the patient could be saved? That is the same reasoning of using catheters, isn’t it? If we can access every single site inside our body, and conduct localized operations such as tissue removal, drug delivery, sampling, etc., we will surely be able to treat more diseases better. This is the premise for our following discussion.

The Healthcare Potential

The small-scale robots attract much attention for the promised capability to access hard-to-reach and constrained space inside human body, conducting medical operations at a resolution and delicacy that is unimageable before. They can navigate within our body using the natural networks of ducts and cavities, such as our blood circulation system, digestive system, urinary system, reproductive system, etc., pushing minimally invasive healthcare and precision medicine to a whole new level. This potential is just fascinating. And we are reasonably confident that this potential is true, as long as we can make it happen. Once it happens, it will become an enabling tool that unlocks tons of new possibilities in healthcare. Diseases will become less dreadful as doctors don’t need to “cut patients open” that often and implantable small-scale robots will also help diagnose diseases at an earlier stage. This promised paradigm-shifting potential in healthcare is so crucial and intriguing that I think it is the single most important motivation for the rapid advancement of small-scale robotics. At that future time when this potential is achieved, small-scale robotics may no longer survive as a research field because the maturity of the technology, but I bet most researchers in this field are more than happy to help it happen and then find other topics to work for a living.

Other Potentials

Of course, the development of small-scale robotics will not just impact healthcare. Having a miniaturized robotic tool brings new possibilities to various fields, such as microfabrication, lab/organ-on-a-chip, environmental monitoring and remedy, deep sea/space exploration, etc. We human beings are at the meter scale. But our curiosity spans from subatomic sizes to lightyears. We have invented a library of tools to help us explore the world. Moving towards a larger size scale, we invented cars, trains, and planes to help us cover a distance that would have taken a person’s whole lifetime to travel. Similarly, moving towards a smaller size scale, we invented microscopes and micromanipulators to maneuver cells and even a single atom. Small-scale robotics is the extension of one of our greatest invention, robotics, to a smaller size scale. Simply put, whatever a conventional robot can do, we hope a small-scale robot could also do similar things, just at a smaller size scale.


It will be lying if I say I am not happy to see the prosperity of this field. But I am indeed surprised by its advancement speed. And that also raises some concerns for me. A fast uprise is often followed by a steep downturn. People are enthusiastic about it. People cannot wait to see the next-generation small-scale robot, then the next-next-generation. But things won’t just go well because we hope so. We will meet frustrations, roadblocks, and even dead ends. I am worried that such an acute interest in pushing this field forward will eventually backfire, luring researchers to quick success by not asking the inconvenient questions. In the very near future, when all low-hanging fruits have been harvested, will we be able to deliver the next milestone to keep the field afloat? Who is quietly cracking the hard nut while others are chasing the waves? I hope that, many years later when people look back, small-scale robotics is not a flash in the pan. Afterall, I’ve invested a decent amount of my life into it. I hope it goes somewhere.

by ZHANG Jiachen on 30 Oct 2022