“Measure twice. Solder once. Learn forever!”
Title: Professor and Graduate Group Chair Courses: Fluid Mechanics and Discover, Design, Build and Test: A Hands-On Introduction to Product and Device Design Focus Areas: Soft Matter and Complex Fluids; Cellular and Biomolecular Engineering; Molecular Simulation and Thermodynamics
Dr. Crocker’s research is multidisciplinary, and he has made pioneering contributions to the fields of soft matter and biophysics, in particular the use of optical trapping and microrheology methods, and the use of DNA for forming colloidal crystals. Open-source software tools he co-developed for particle tracking are in use by hundreds of research labs around the world. He was awarded a Packard Fellowship in 2002 and a ‘Brilliant 10’ award in 2005. His professional service has largely been to the Colloid and Surface Chemistry Division of the ACS and the Division of Soft Matter (DSOFT) at the APS, who named him a Fellow in 2018.
What courses do you teach, and what excites you most about them? I really enjoy teaching fluid mechanics and taking advanced calculus concepts that the students have only previously experienced in a math course, mapping them onto real world problems and connecting them to the students’ physical intuition. My challenge as an instructor is to overcome student intimidation by breaking down the ideas, and introducing them in a measured way, adding complexity at each step.
I enjoy teaching labs, because it is close to what got me into science and engineering in the first place. With Hands-on design, I get to take a bunch of students who are completely clueless about the material and introduce them to a wide range of interrelated topics, let them learn from a lot of mistakes, and in a half credit of contact time, they are comfortable building remarkably complex devices hooked up to computers.
Can you describe one topic or problem students find especially interesting or surprising? Nearly every project the students build, from a simple LED lighting up, to a glucose meter doesn’t work the first time they turn it on. The most interesting part for me is teaching them how to debug and fix their projects, first by doing it for them, and then later by guided questions.
What’s something students tend to struggle with, and how do you help them work through it? There are several important but subtle concepts in building electrical circuits, like what is a ground, or an output impedance, that students struggle with. The activities in the first lab part of the class demonstrate these concepts for them, or specifically what goes wrong if the concepts are not handled correctly.
Do you have a favorite example, analogy, or classroom moment that brings your subject to life? When the student get their final projects to work, whether it is seeing a pulse waveform on a computer screen, or a glucose concentration readout, their excitement is palpable.
What’s a memorable question a student has asked you that made you stop and think? “Why does my X/Y/Z not work?”
If your course had a tagline, what would it be? Measure twice. Solder once. Learn forever!
What’s one piece of advice you’d give students taking your class (or any CBE class)? Black is negative. Red is positive.
Looking back, what do you hope students carry with them long after graduation? I hope they carry with them a sense of confidence that they can understand how complex instruments work.
