EPDM vs. Windchill

Anyone have any thoughts? We are at a junction where we have to make a decision. I am quite interested in any experiences any of you may have with either system.

continue…

this blog is not dead, long live hardware

Much of my content here is search engine bait, but this one goes out directly to my wonderful subscribers and commenters. As you may have noticed, I have not updated this post in a while. Those of you who have been subscribing to blogs for a while might be thinking "great, another abandoned blog". Not […]

continue…

quanttus is hiring!

I recently joined quanttus, a really exciting new startup based at the CIC in Cambridge. We're growing really fast (I was the first hire in the ME deparment) and are looking to hire, among other things, another senior mechanical engineer. So read the description below and, if it feels up your alley, apply here Position […]

continue…

disrupting CAD: The future is open

One of the more controversial posts I've written was about how unigraphics sucks. I wrote it a few years ago and have occasionally fielded comments from people with strong opinions. In responding to one earlier today I looked at the updated chart for the first time in a while and couldn't help but notice the […]

continue…

brainstorming checklist for product design

Every project is different, but principles tend to repeat themselves. When faced with a problem that doesn't have an immediate solution, I find it worthwhile to get a few smart people in a room, get them fed, and think about the problem. That's where the hard part comes in: just how should we think about the […]

continue…

the zen of risk: thoughts on program management

Program management, to me, isn't fun. I don't like to think about it. I would much rather design a mechanism, run a simulation, build a robot, create a visualization, or perform some data analysis. The thing is, all the cool things I like to do take place in an environment (the program) that is completely defined by how […]

continue…

Using a Fast Fourier Transform to analyze test data

A Fast Fourier Transform can take nosiy data that look like this: And give you something much more precise and useful (ie the freuqnecy, amplitude, and phase offset), like this: Usually you see these used for digital signal analysis, but I've found it to be really helpful when analyzing sinusoidal data coming from prototype mechanical systems. […]

continue…

the future of mechanical engineering

In times of change learners inherit the earth; while the learned find themselves beautifully equipped to deal with a world that no longer exists. First, the doom-and-gloom: I think we are at the beginning of an era of great change in the mechanical engineering discipline in general, and product design in particular. A grand statement, […]

continue…

video: flow measurement principles

I've recently had occasion to look at various methods for measuring fluid flowing through a tube. In my research I came across a really great set of videos from Endress Hauser that describe different methods for doing exactly that. An interesting distinction that I was previously unaware of is that some methods (e.g.  the venturi […]

continue…

Robotic insects make first controlled flight

A while back I shared a video where Rob Wood of Harvard discussed the challenges inherent in flight at the scale of 100mg. Well they were recently successful. Check out the video.

continue…

507 Mechanical Movements Site

For a while now I've been recommending 507 Mechanical Movements as a good reference for brainstorming mechanisms. Well, maybe it's about to get better thanks to Matt Keveney at 507movements.com. He is setting out to animate all 507 mechanisms and make them freely available. This is no small undertaking. I attempted it myself and got to ~10 […]

continue…

the ability to learn

I'm fond of telling students that the most important skill they are developing is the ability to learn. In that vein I just had to share this graph from Seb Paquet:

continue…

what I've been up to...

My posts have been less frequent in the past few months, and I want to ensure to you that it isn't because I've got nothing to talk about. Quite the opposite, there is so much going on that it is difficult to carve out time to sit down and write an article. I hope to […]

continue…

injection molding: the process of transferring to production

A few months ago my team and I wrapped up a pretty big project. It was big in terms of effort, annual volumes, as well as the size of the parts themselves (injection molded parts well above 1 pound). It was a really cool project. Unfortunately I can't tell you anything about it (yet... they […]

continue…

how i feel after multiple crashes, freezings, and sketches not properly solving

....just to name a few gripes.

continue…

video: bipedal robot on a bicycle

I've been doing a lot of robotics lately. Mostly looking at platforms for a demo (Raspberry Pi vs Arduino vs Beagleboard) as well as libraries (ROS) for controlling the robot. Also the cost/benefit of controlling via MATLAB, LabView, or Python. In the course of that grunt work (which I will be writing about...first I've get […]

continue…

good things come to those who wait?

“Things may come to those who wait...but only the things left by those who hustle.” -Abraham Lincoln

continue…

what high school can teach you about product development

Art Rousmaniere, a man that doesn't write very often and whom I hold in very high regard, has written an article over at Farm distilling the connections he's made between a decade of coaching FIRST robotics teams and multiple decades in product development. It's a great article, you should go read it.

continue…

the best GD&T training you will ever find

I've talked a lot about tolerance analysis on this site, but I haven't talked too much about GD&T. I suspect a few of you don't know what GD&T is (Geometric Dimensioning & Tolerancing), most of you have probably used it a little bit, and a sliver of you are gurus. Don Day is a guru, […]

continue…

why mechanical engineers should take MIT 6.00x (starts monday 10.01.12)

I recently mentioned that MIT was now offering their 600 course, Introduction to Computer Science and Programming, online via edx. Well I've signed up. It starts monday and I'm excited. More importantly, you should be excited. You should be excited because programming is a skill you need, and it's never been offered for free in […]

continue…

just love this image

continue…

minimalism: you don't need to buy this

My life tends to skew towards what one might call 'minimalist'. I exemplify this in my life and I attempt, as much as possible, to implement it in my designs. I encourage you to spend a few minutes with this video. If you're feeling this video, you might also appreciate new vs perfect.

continue…

master/skeleton modeling - wrapping your mind around it

This has the potential to be the least-polished post I've ever put up here (long-time readers will know that means something). Why is this so? I'm giving a presentation tomorrow on a topic I know very well, but have never presented on before. It's a topic that is certainly relevant to mechanical engineers (and thus […]

continue…

computer vision in early stage product development (with code)

Followers of the blog know that I've been playing around with python and computer vision. Well I recently wrote an article describing how computer vision can be used in product development. In the video below I go through the steps necessary to extract data from someone walking during the heel-strike to toe-off portion of the […]

continue…

the essence of engineering

From Proffessor Eric Grimson at MIT ...what we try and do is, we take a new problem and map it onto an old problem so that we can use an old solution.In order to be able to do that, it's nice to have in our heads an inventory of previously solved problems to which we […]

continue…

lockable gas springs (or: how an office chair works)

I recently had occasion to look into lockable gas springs (like the ones you might find in an office chair). I already had a pretty good idea how they worked, but I've never seen it illustrated as clearly as it is over Bansbach. They also have a lever-, cable- (you may not have heard of […]

continue…

learn python at MIT... online

A while back I mentioned that MIT had done something innovative: they offered a course (6.002x – Circuits and Electronics) online that, upon attaining a passing grade, would result in an actual credential. Well they’ve since expanded and recruited Harvard and Berkeley to the effort, and the result is edX. In particular I’d like to […]

continue…

video: best explanation of how differentials work

I just came across this video via reddit. It does the best job I've seen of explaining a differential. It starts with a pair of motorcycles explaining how wheels turning on a larger radius need to turn faster than the wheels on a smaller radius in order to keep the same angular position, and progress […]

continue…

what students and employers should know about successful co-op programs

For a few years I was a part of our co-op recruiting and hiring process. I've since stepped back and let some others have a go at it, but the lessons I've learned remain. Lee Panecki, one of our several success stories (success being defined as a co-op that we ended up hiring full-time) has […]

continue…

360 interactive panorama from curiosity

I'm sure I'm not the only one who has been geeking out about Curiousity... here's something to play with: via The Atlantic Curiosity rover: Martian solar day 2 in New Mexico

continue…

an argument for more prototypes

If you've ever advocated (i.e. solicited funds) for more prototypes, you know it can be a tough sell; how do you articulate the value of frequent  prototyping during the development process? I find it useful to consider an illustrative (if simplified) anecdote. Imagine an engineer, Fred, who needs to develop a mechanism(lets say for automatic […]

continue…

casting technique selection guide

Cleaning out my desk area yesterday I threw away a bunch of vendor pamphlets. The only ones I kept (the vendors reading this should take note) were the ones that had a useful guide to their respective technology; not the ones that talk about how they are a family business that has been dedicated to […]

continue…

measuring angles in opencv

Not too long ago I mentioned I was playing around with opencv and python. Well, in between client work I've moved a bit forward. Now I'm calculating the angle of a line between two tracked points relative to the horizontal. It's a relatively straightforward thing to implement (although my code, below, isn't exactly pristine), and […]

continue…

the program manager's paradox

Projects always take longer than you expect, even when you account for the fact that projects always take longer than you expect. a.k.a. Hofstadter's Law

continue…

playing around with computer vision, python, and opencv

I have been playing around with Python quite a bit lately and have recently been playing around with OpenCV (Open Computer Vision) to see what if I couldn't get it to track something. Well I did (that something being my son's toy bear), and it was surprisingly straightforward (and free!... take that MATLAB) Anyway, I'm […]

continue…

bayesian statistics: an introductory example

Bayesian statistics are widely used in fields like robotics and machine learning. I've been playing around with the theories over the past few months (sorry for the lack of posts by the way), and recently came across something with a high (worth sharing)/(time to write a post) ratio. It's called the cookie problem: Suppose there […]

continue…

video:pulse width modulation

Pulse Width Modulation is a workhorse in  electronics. Essentially, PWM is a fancy way of saying: turning the power on and off really fast such that it looks like you have a constant stream of a lower amount of power. A common use of PWM is for the control of motors. Especially in the case […]

continue…

slick robotic arm used for dynamic high speed video

via reddit. skip to 2:20 to see the robot. THE MARMALADE Identity from schoenheitsfarm production on Vimeo.

continue…

muscle as an actuator

I recently had occasion to compare various types of actuators. As I was going through the traditional technologies (pneumatic, hydraulic, electric), I came across a quite amazing site: http://actuatorweb.org/ What's awesome about it? This table pretty much sums it up, but be sure to check out the site to see the rest. Muscle is a linear […]

continue…

the body is amazing

consider the following: I burn ~70 calories per hour while sleeping. Science tells me that's 81 Watts. That's about what my old CRT monitor used. The body makes electronics look downright ineffeccient.

continue…

why you need to build more prototypes

Physical prototypes are expensive, but not making them is even more so. The next time you are trying to decide whether or not a prototype is worth the money, consider these two things: your design team is never more productive than the few days after receiving a prototype prototypes force stakeholders into consensus; it insists […]

continue…

Joichi Ito on the future of science and technology

Joichi Ito, director of the MIT Media Lab, prompted by Steelcase: One hundred years from now, the role of science and technology will be about becoming part of nature rather than trying to control it. So much of science and technology has been about pursuing efficiency, scale and “exponential growth” at the expense of our […]

continue…

notes from ANSYS' confidence by design workshop

I spent the day today down in Waltham at the ANSYS confidence by design workshop. I'll write in depth about some of the topics later, but for now I'll just leave my notes right here. submodeling A coarse mesh will give accurate displacements, but not stresses. This is a reflection of the fact that the […]

continue…

largest CAD database you've ever built?

While I'm waiting for ~15,000 features to regenerate, I find myself wondering what size databases you all work with.   ?

continue…

prototyping elastomers

A while back I wrote about urethane castings. In the article I said the following regarding prototyping: Urethane castings are your only choice for elastomer prototypes of any decent quality. Period. I caught a little bit of flack for that. Specifically, a few people were keen on mentioning Objet's Tango materials. I'm not particularly keen […]

continue…

the third industrial revolution

long time readers will know that I'm a big fan of The Economist. Well, they continue to earn my subscription dollars. Over the weekend I read their 14-page report on what they are calling the third industrial revolution. Simplified, their premise is this: As manufacturing becomes more and digitized, disruptive opportunities will be created. I […]

continue…

amazon vs. mcmaster

Looks like amazon is trying to compete with McMaster Carr. At least that's what it looks like when you first land on amazonsupply.com At the moment it's no competition: Amazon Supply doesn't even have CAD models. Still, with amazon's logistical know-how it's not hard to imagine them dethroning McMaster as the hardware supplier of choice.

continue…

the one thing you need to know about FEA

By definition, the people performing FEA studies know more about it than most (if not all) of the people reviewing the final report. This can become a problem if, among the rainbow colored plots and animations, a less savvy reviewer finds themselves believing that the simulation is a reflection, instead of an approximation, of reality. […]

continue…

building adaptable CAD databases

I recently wrote an article on adaptable CAD databases for a medical device magazine. The premise is that in the near future (or present day in some cases), the adaptability of a CAD database will become a competitive advantage. My economic argument (which I only hint to in the article; it's more of a technical […]

continue…

good process: simplified

On Monday I'll be visiting Northeastern's human factors class to give a guest lecture on the role human factors plays in (medical) product design. The thing is this: you can't really talk about medical product design without talking about verification and validation, but going deep into it can become a bit of a snooze festival. […]

continue…