Subject Code/Name: BMEN20001 Biomechanical Physics and ComputationThis is a relatively new subject, 2016 semester 1 marked its second offering. It's still got some teething problems to grow out of, which I would put down to an underexperienced teaching team.
The subject's aim is to serve as a combination of
ENGR20004 Engineering Mechanics and
COMP20005 Engineering Computation, embedded in a biomechanics context. That is, we study the same topics but where engineering students might focus on steel bars supporting loads we'll look at human limbs holding weights. We also spent some time considering the complications that arise when analysing
organic materials such as bone and skin.
The intended audience is biomed students looking to master the physics foundations necessary for studying biomechanics. I don't fit this description, as a Physics and Computing student interested in applying what I know in a new context. For someone like me, this subject wasn't that bad. It acted as an interesting extension of VCE Physics topics (the 'mechanics' core AoS and the 'structures and materials' detailed study) plus an introduction to yet another programming language (MATLAB).
However, for someone with zero background in physics or computation (the intended audience), I think this subject would have been a lot more difficult to manage. I'd say
possible with a fair bit of work getting up to speed on the basics, but otherwise the necessary time wasn't really spent laying those foundations, and the MATLAB learning experience was liable scare anyone new to computing away from the field for good.
The rest of this review is pretty long. I've included a lot of detail about the topics we covered, the class experience, and the assessments. I hope it aids people in their decisions about this subject, and helps people taking it / required to take it know what kind of experience to expect.
Workload:Three 1h lectures (less on average, however; see comments!)
One 2h workshop (sometimes a tutorial, sometimes a MATLAB class)
Assessment:5% - Assignment 1
10% - Assignment 2
10% - Assignment 3
15% - Assignment 4, groups of 4
10% - Mid-semester test
50% - 3h exam in exam period
Lecture Capture: YPast exams available:There were no past exams available because all of the previous exam questions had been included as tutorial questions (only one previous exam this time round).
Lecturer:The content lectures were presented by Vijay Rajagopal.
Additionally, there was a guest lecture from one of the tutors, a series of three guest lectures on head injury by Andrew Short, and a series of three further guest lectures from various biomechanics researchers.
Year & Semester of completion: 2016 Semester 1
Rating: 3/5
Your Mark/Grade: 95
Technologies:This subject served as an (admittedly poor) introduction to programming using MATLAB. Learning MATLAB was the focus of most of the workshops, and the first three assignments were mostly programming.
Textbook Recommendation:There were four recommended textbooks, from which the course material was drawn. These were:
- Humphrey JD, and Delange SL, An Introduction to Biomechanics
- Nihat O. Nordin M, Goldsheyder D, and Leger D, Fundamentals of Biomechanics, 3rd Edition
- Meriam Jl and Kraige LG, Engineering Mechanics: Dynamics, 7th Edition
- Hibbeler RC, Statics and Mechanics of Materials, 3rd Edition
I personally used a very old edition of Hibbeler (like 1991 or something, I think it's technically not even the same book as it was just called 'Mechanics of Materials') and I found it absolutely fantastic, but that's coming from a strong maths and physics background and with a preference for comprehensive textbooks that leave no ambiguity and don't shy away from complexity. It was also a regular engineering text, with no biomechanical context. Nevertheless, it was an enlightening read; one of those textbooks that answers all of your questions as soon as they form, and also really gives you a big-picture view of the material.
Some of the other texts might serve as a better introduction to these physics concepts, but they seemed to also assume a bit of a background in biology, of which I had none. Therefore, I recommend the Hibbeler option for anyone with my background.
Comments:Content:The 'physics' in 'biomechanical physics and computation' stands for
statics (the study of materials undergoing forces but not moving), and
dynamics (the study of objects in motion). These topics were the focus of the lectures. The 'computation' represents an approach to these problems that utilises computers, which can do the grunt work of crunching numbers, repeating calculations and plotting graphs. This was the focus of the workshops. Of course, everything was looked at through a biomechanics perspective.
In terms of statics, we quickly whizzed through the basics of forces and moments (a.k.a. torques, shout out to VCE Physics students) and then looked at the much more confusing topic of
internal forces and moments (like within bones or at joints). After that was a look at the concepts of stress and strain (normal and shear), extending to applications of forces in 3D, as well as other material properties (especially those relevant to biological materials, like skin). We were going to discuss beams but skipped that topic and went straight to axial loading, and finally looked at thin-walled spherical and cylindrical pressure vessels (arteries/veins and aneurysms!).
For dynamics, again we quickly touched on the basics of motion and relative motion of particles - position, velocity, and acceleration. We also looked quickly at work and energy. We then spent some time on linear momentum (for collision analysis) and things like the coefficient of restitution, and then on rotational motion and angular momentum. Finally, we had a brief look at rigid bodies (bodies bigger than a particle, where rotation matters) and some more powerful and general equations of motion that can be used to analyse rigid body systems.
Despite the appearances from the handbook entry, I think this subject was pitched a little too fast as an introduction to these physics concepts. I think for someone completely new to mechanics (statics and dynamics), a bit much was assumed and the basics/foundational points were skimmed over. I would recommend that someone in this position try very hard to master the basics before tackling the later topics, and recommend resources such as khanacademy's high school motion playlists for this purpose.
The 'computation' part spanned everything from variables and data types to control structures (branching and looping) and functions. Despite the presence in the handbook, numerical methods for solving differential equations were not explored. Numerical simulations were carried out, but they were for simple projectile motion situations. This was the domain of the majority of the workshops, which I'll talk more about later.
Lectures:Vijay's lectures weren't bad, but I'd say as a relatively new lecturer he's definitely got some improvement to do in terms of presenting these concepts. This semester, there were a few topics that seemed to be lost on students. One was a matrix method for converting between 3D stresses and strains, but this was identified and I think Vijay is going to use a much more intuitive approach next semester. Another (this wasn't so much the feeling of the cohort but of myself) tricky point that was neglected was the difference between tensorial shear strain and engineering shear strain. It turns out that tensorial shear strain (ε), used in the matrix equations, actually has twice the value of engineering shear strain (γ), used in other formulas. This subtle point was hidden in the definitions of the matrix equations on the slides and I feel like more attention could have been drawn to it, and a very clear distinction made between the shear strains.
Apart from a few tricky points like this, it's easy to see why Vijay always looks so happy and cheerful when he's lecturing - you can tell he loves sharing his passion for biomechanics with people and teaching the concepts too. He was very kind, friendly, and approachable. His priority was everyone's understanding, which is why he always went out of his way to give the best explanations possible (e.g. repeating a lecture or two in response to student questions). Because his heart is demonstrably in the right place, I have no doubt that he'll continually improve his teaching quality in semesters to come.
Vijay also adopted the unconventional (but effective, IMO) strategy of offering lectures dedicated to working through problems, as a demonstration of how to apply the equations and laws we were learning. This was good because particularly in physics, getting into the process of using theory to solve problems is just as important as getting your head around the theory in the first place. I am glad that this was reflected in the lecture schedule.
The other thing about these problem classes, along with the large number of guest lectures (7 in total) and the mid-sem test, was that it left a reduced number of content-lectures. From 3 lectures a week, there ended up being 18 assessable content lectures. This made for a fairly light revision load, and it was very manageable to master the material in swotvac (fine-tuning understanding of pre-MST statics content, and conquering dynamics too).
Workshops:Unfortunately, the workshops for this subject were quite a big let down. Since I came with prior knowledge in computing, I was able to ignore the explanations of the foundational programming concepts. I fear, however, that other students were not so lucky. Nothing that was presented in the workshops was useful beyond what a short online MATLAB (or any other programming language) tutorial would offer, and some of the explanations were outright incorrect and potentially damaging to students' basic understanding of programming concepts.
I don't have faith that the tutors will improve in future semesters (unless they are replaced). If I'm right, then for anyone new to computing and interested in taking this subject, I recommend treating everything presented in the workshops as suspect. Then, I'd advise taking the list of content presented and seeking alternate resources for learning those things. I didn't get a chance to explore it, but I'd be willing to bet that
this online course from MIT (the small part of it that is relevant) runs rings around these guys. Short of that, you can PM me on ATAR Notes to help explain a piece of MATLAB code. You can search on Google. Anything other than trusting the demonstrators with your impressions about computing - it's such a wonderful area of study and it really hurt me to see it presented like it was.
A few of the workshops were not allocated to MATLAB, but instead to worked examples, kinda like in the lectures. Due to the general incompetence of the demonstrators, this was equivalent to working through the problems alone or with peers. This does bring me to a small point of confusion, though. Each week, topical 'tutorial' questions were uploaded. Sometimes, a selection of these questions were covered in an example-lecture. Other weeks, the workshop was dedicated to working through them. Either way, the tutorial sheets were just a source of application questions (with accompanying solutions, of varying correctness) even though there was no official 'tutorial'.
Assignments:The first three assignments involved a mechanics problem followed by a short MATLAB scripting task. The problem was that the instructions weren't clear, and often the incomplete information given was not really enough to complete the tasks. In several cases, LMS announcements came out afterwards clearing up some of these points, but I think it's really important to minimise this kind of thing - obviously assignment tasks should be as complete as possible upon release so that students are not disadvantaged in the time they have to complete them waiting for things to be cleared up. Also, any assumptions made should not later by invalidated by LMS announcements. These issues generally didn't affect me, but they made the assignments come across as incredibly unpolished overall. I hope that in the future these little glitches can be ironed out before assignment release.
Then came the fourth assignment. In about week 7 it was announced that the final assignment would involve group work, which was the first we had heard of it. During week 9, a set of three guest lectures on head impact and head injury was presented by guest lecturer Andrew Short. That week, the workshop was replaced with a fake-head-dropping experiment, after which we were ushered into groups of 4 students and vaguely told that the final assignment would be a four-part practical report based on these experiments.
Later, more detailed information (almost in the form of an assignment specification!) surfaced. The report was to have four parts: a literature review on impact testing, a report on the experimental procedure and equipment, and analysis of the results, and a discussion of the findings and any compliance issues with respect to an impact testing standards document we were given. Most of the descriptions of the expectations were ambiguous. Some of it was incomprehensible. Within my group, I took primary responsibility for the analysis section since nobody else really wanted to use MATLAB. This section, in particular, was a shambles. Part of the task was to analyse the motion of a fake head as it fell and bounced on different materials. This was meant to be conducted by manually tracking some dots attached to the head form in video recordings of the drop tests. This frame-by-frame tracking (as demonstrated in the week 10 workshop) was quite a long process, and we were looking for a way to automate it. In the week 11 workshop, we were provided with some MATLAB scripts that attempted to track the dots for us. However, these scripts were very fragile, and even after repeated updates released by Andrew, failed to analyse all of the videos without crashing. I ended up streamlining the manual tracking script and using that instead.
In the final week (much to my frustration, for the same reasons as above), Andrew took the LMS discussion forums to construct an FAQ list, detailing things assignment advice (mostly things that should have been in the initial specification). At this point, it was far too late to perform our analysis again and so we just had to stick with our manual data. We did manage to incorporate some advice into the other sections. However, it just shouldn't have been expected that we would be completing the majority of our work in the final week before the due date.
Worst of all, one night before the due date, another (apparently, finally working) version of the analysis script was released. Other scripts were still broken and I never had a chance to try the new analysis script but I have a hunch that it wouldn't actually be free of bugs, but attempting to release the required material for the assignment the night before the due date when it should have worked from the beginning really angered and upset me.
I think the entire cohort felt miserable about the impossibly frustrating final assignment. I can't imagine it will survive the SES reviews unchecked, and I sincerely hope that it is improved for future iterations of the subject.
The assessment was plagued by other small administrative issues such as the due-dates not being announced with the assignments, and LMS resubmissions before the due-date being accidentally disallowed on 3/4 of the assignments (those administered by the demonstrators, ha) just caused a lot of unnecessary stress.
MST and Exam:Though tutorial and lecture examples were a mix of typical engineering examples and simplified biomechanical examples, the questions on the MST and final exam were largely drawn from a biomechanical context. Both tests were fairly well-balanced in terms of time and difficulty, with the majority of questions being similar to those found in lecture examples or tutorial sheets. I made an effort to work through every tutorial question before the exam and was rewarded for that this preparation by an exam with no surprises. However, the difficulty of the final exam questions was a little higher than that of most of the tutorial questions. I'm certainly glad we had three hours because I needed all of it to complete the paper.
Overall:In taking this subject I accomplished my goals of learning about applying my physics and computing knowledge to a new and interesting domain. However, as a subject aimed at introducing biomedicine students to physics and computation, BMEN20001 has a fair way to go.
The assignments needed to be better thoughtout, and to provide all necessary information at release time. The demonstrators were shocking, and the workshops were possibly worse than useless. The pacing of the content was out of step with the impression given by the handbook entry, and more attention could have been paid to the foundational concepts (or more careful attention; it's just very important to avoid introducing confusion at that level because it underlies the rest of the entire subject and indeed all of Classical Mechanics!).
Hopefully, the coordinators listen to the feedback they receive and take steps to improve on some of the points. For those considering taking this subject, think about what you want to get out of it. For those who need to take this subject, I'm sure you'll be able to get through it, and feel free to PM me with any questions you might have!