Jump to content
Mechanical Engineering
  • entries
    94
  • comments
    475
  • views
    49,277

About this blog

A Journal of Applied Mechanics and Mathematics by DrD

Entries in this blog

Two Short Math Problems

Mechanics Corner A Journal of Applied Mechanics and Mathematics by DrD, #40 July, 2017   Two Short Math Problems Do you ever read the ads that appear on ME Forum? I try to avoid them as much as possible, but an organization called BRILLIANT has put up some interesting math problems of late that have caught my eye. Two of them are the subject of today's post. The first problem that I want to discuss is actually more recent than the other, but it gives us a good plac

DrD

DrD

Comments on a Textbook - Khurmi & Gupta

Mechanics Corner A Journal of Applied Mechanics and Mathematics by DrD, #39 (c) Machinery Dynamics Research, 2017 Comments on a Textbook Theory of Machines by R.S. Khurmi & J.K. Gupta 1 Introduction Recently, through the wonders of the Internet, I have come across a copy of the textbook Theory of Machines by R.S. Khurmi and J.K. Gupta (S.Chand & Co., Ltd., 2005). Since theory of machines has been my primary technical interest since the early 1980s, I was interested

DrD

DrD

Rocket Homework Problem

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD, #38       Machinery Dynamics Research, 2017 Rocket Homework Problem Introduction     Most engineers find problems involving rockets to be exciting. There is something about a rocket that fires our imagination, whether we think of going to the moon or one of the planets, or simply of shooting down an incoming missile. The subject of this post involves a rocket on a mobile launcher. The rocket is i

DrD

DrD

Where Would You Publish It?

Mechanics Corner Where Would You Publish It? Since long before my time, there has been a desire to have important results published where they become accessible to many others. Some of the great names, such as Newton, Euler, Bernoulli, and others, we know primarily because of what they published. Their work formed the fundamentals upon which modern engineering and science is built. Publication of research results has long been particularly important to faculty members; it is often take

DrD

DrD

Two Balls Rolling On An Incline

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD, # 37     29 April 2017 Two Balls Rolling On An Incline A Problem Where I Learned Something New Introduction     In previous articles, I have mentioned another web site called Physics Forums (PF) where people post problems for which they need help. In this note, I want to present to you one such problem and it solution, along with a new insight that came from another commenter at PF, one of the advi

DrD

DrD

Base Acceleration Problem -- #36

Mechanics Corner A Journal of Applied Mechanics and Mathematics by DrD, #36   Base Acceleration Problem Introduction In a recent post (#35) I mentioned that I often participate in another forum called Physics Forums (PF). The problem that I want to discuss here is an elaboration on a problem that recently appeared at PF. I'm going to add a little bit of complexity to the problem (the problme as stated at PF was extremely simple) in order to make a particular point.

DrD

DrD

Good News -- Bad News -- Rolling Disk in a Rolling Ring

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD, # 35       Machinery Dynamics Research, 2017 Good News --- Bad News Rolling Disk in a Rolling Ring      Introduction     Well, it looks like Mechanics Corner is back, at least in terms of an occasional post. It will probably be less frequent than previously, but there are just too many interesting things to talk about to remain entirely silent! The title for this post may leave you wondering wh

DrD

DrD

Last Post -- Time to Hang It Up

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD     © Machinery Dynamics Research, 2017 Last Post Time to Hang It Up     This will be the final post of Mechanics Corner here on Mechanical Engineering Forums. It has run almost exactly two years, and there have been ups and downs along the way. In this final post, I want to reflect a bit on my original goals for the blog, and also on what has actually happened. When our host first proposed to me t

DrD

DrD

A Problem in Statics & Dynamics, #34

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD, # 34     © Machinery Dynamics Research, 2015 A Problem in Statics & Dynamics           Introduction         A problem was recently posted on this Forum, requesting help, that has led me to consider a somewhat more general problem for this post. The scope of this post will include the original problem, although not by the method required there, but will also go beyond to a more general geometry.

DrD

DrD

Advanced Polynomial Curve Fitting

Mechanics Corner     A Journal of Applied Mechanics & Mathematics by DrD, #33     © Machinery Dynamics Research, 2016 Advanced Polynomial Curve Fitting     The use of polynomials to fit engineering data is a common engineering practice. In school, we learn that "A data set consisting of n data points ((x_{i},y_{i}), i=1,2,3,…n) can be exactly fitted with a polynomial of degree n-1. Thus three data points can be fitted exactly with a quadratic expression, four data points ca

DrD

DrD

Braced Cantilever

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD, # 32     © Machinery Dynamics Research, LLC, 2015 Braced Cantilever Introduction     Anyone who has actually gotten into machine design is familiar with this difficulty. Consider the situation where a project is well advanced, many plans have been made, and it is all based on the assumption of the adequacy of one particular part. When you finally get to the detailed analysis of that part, the calculat

DrD

DrD

ODE Solution --- Fail!!

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD, # 31       Machinery Dynamics Research, 2016 ODE Solution --- Fail!!      Introduction     Digital computation has become a major tool for engineers, and it is a great benefit. It can also lead to many pitfalls for the unwary. This note is about the latter, a potential pitfall that many engineers risk on a daily basis, most of them with little awareness of the danger.     Early in the developme

DrD

DrD

Where is this?

Does anyone recognize where this video is shot? Is it a group of students at a school (what school?), or is it an industrial site (what company)? I am anxious for someone to locate this for me, please. DrD   Saurabh Jain, our host, has identified this location for me, and that is much appreciated. When I watched the video, I was aghast at all those nearly bare feet in a machine shop! I can appreciate that in Indian culture, the simple sandals are socially quite acceptable, bu

DrD

DrD

A Question for Readers

Many of you have asked me various questions, so now it is my turn. Let me lay a bit of background first, and then the questions.   I have had some conversations recently with JAG (one of the other writers here at ME Forums) regarding the choice of software for 3D modeling and analysis. JAG has made some excellent suggestions, specifically a cloud based program called Onshape. Unfortunately, for reasons that are unclear, my computer cannot run Onshape; I have worked with their help peop

DrD

DrD

Becoming An Expert -- Part 3

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD     © Machinery Dynamics Research, 2016 Becoming An Expert -- Part 3      Introduction     In the previous article on Becoming An Expert--Part 2, I mentioned that there were two big issues for the engineering analysis section at my Houston position, the first being the matter of seismic survivability and the second being torsional vibration. The first item was dealt with in Part 2, and in this art

DrD

DrD

A Comment Remembered

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD     © Machinery Dynamics Research, 2016 A Comment Remembered          Recently, in connection with one of the posts on Becoming An Expert, one of the ME Forum readers made a comment to me, something about seeing everything in terms of differential equations. That comment brought to mind a comment made to me many years ago that I want to pass along to you today.     Most of my college education was at th

DrD

DrD

Becoming An Expert -- Part 2

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD     © Machinery Dynamics Research, 2016 Becoming An Expert -- Part 2      Introduction     In the previous article on How To Become An Expert, I covered a lot of points in generalities with some short anecdotes from my own experience. In this article and the next, I will describe in considerably more detail a critical period in my own formation, an time of considerable professional embarrassment w

DrD

DrD

How To Become An Expert

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD     © Machinery Dynamics Research, 2016 How To Become An Expert      Introduction     This is going to be another of those personal experience/opinion pieces, so if these bore you, be warned! This may be the time to click on something else.     A reader recently wrote to me asking how to become an expert. I have to tell you, I don't spend much time thinking about being an expert, but I suppose o

DrD

DrD

#28 -- Analytical Design -- Part III

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD, # 28     © Machinery Dynamics Research, 2016 Analytical Design -- Part III      Introduction     In Parts I and II of this series, we began looking into the design analysis for an emergency steam cut-off valve for a nuclear power plant. Part I simply posed the problem, and Part II got into the detailed kinematic analysis of the four bar linkage that is to control the motion of the plug as it shut

DrD

DrD

John Deere & Culture Shock

More than once, I have remarked in this blog about the lack of participation. I have been mystified by the lack of questions and comments on my articles. Even those that get several thousand views, often have no comments at all. I just don't understand it! Yesterday, I had a visit. My visitor is a former student of mine, a fellow that I taught back in the early 1980s. His name is Bob, and Bob was an Ag Engineering student, if I recall correctly. He took my theory of machines class as an ele

DrD

DrD

#27 -- Analytical Design -- Part II

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD, # 27     © Machinery Dynamics Research, 2016 Analytical Design -- Part II      Introduction     In Part I of this series, the problem posed was to apply, as far as possible, the available knowledge of mathematics and science to the design of an Emergency Steam Shut-Off Valve, to be gravity driven as in the sketch below, Fig. 1. The inlet and outlet for the steam flow are both specified to be 0.85

DrD

DrD

#26 -- Analytical Design -- Part I

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD, # 26     © Machinery Dynamics Research, 2016 Analytical Design -- Part I      Introduction     On ME Forums, there have been a number of questions raised about design. Many students are writing in asking for ideas for a senior design project, others are asking for help with a design problem, etc. There has been some discussion about "Just what is design?" That was definitely a question in the min

DrD

DrD

Professional Societies -- Or Not?

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD       Machinery Dynamics Research, (c)  2016 Professional Societies -- Or Not? Introduction     This post is written in response to questions raised by one of our regular participants, a young engineer in Australia. What I have to say here is based entirely on my own, very American, experience, and others may have different ideas. I would encourage a general discussion in the comments, so that we may see

DrD

DrD

War Stories

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD     © Machinery Dynamics Research, 2016 War Stories -- Dr. Jack Levedahl Today I want to tell a few war stories, war stories in the literal sense of the word, in that they all relate in one way or another to World War II. They all center on my friend Dr. Jack Levedahl, a most excellent mechanical engineer and adventurer. Jack was an elderly man when I first met him about 15 years ago, and he has since passe

DrD

DrD

#25 -- A Textbook Statics Problem

Mechanics Corner     A Journal of Applied Mechanics and Mathematics by DrD, # 25     © Machinery Dynamics Research, 2016 A Textbook Statics Problem      Introduction     In the course of each day, I visit many web sites, always keeping an eye out for interesting engineering problems. The problem that is discussed here is one such that came from an American site (more about that web site later). The problem was presented as a simple statics problem, and the poster was ask

DrD

DrD






×
×
  • Create New...