<![CDATA[ - Blog]]>Fri, 17 Nov 2017 07:43:13 -0800Weebly<![CDATA[The Growing Problem of Patent Trolling]]>Tue, 10 May 2016 16:13:15 GMThttp://rollindix.com/blog/the-growing-problem-of-patent-trollingScience Magazine’s April 29th issue carried an article by Harvard and University of Texas researchers with the title above. NPEs (Nonpracticing entities) are now filing ten times as many patent infringement actions as they did ten years ago. According to the article, NPEs are firms that generate no products but amass patent portfolios for the sake of "enforcing" intellectual property "rights." This suing of cash-rich firms is shown in the article to have a negative impact on innovation activity at the targeted firms.
Because of AIA (America Invents Act), firms may now defend themselves against "junk" patents through filing Inter Partes Petitions with the US Patent Office. Unfortunately, this is expensive and most cases end in settlement which encourages further infringement filings by "trolls."
The Science magazine article suggests creation of a mechanism ("advance screening") to weed out low quality patent lawsuits. 
Expert witnesses need to be aware that their clients may be on either side of such a dispute. I suggest that decisions about accepting cases require knowledge of the parties and law firms involved through similar advanced screening by a prospective expert. ]]>
<![CDATA[Window Shade Engineering¬†]]>Sat, 09 Apr 2016 01:30:17 GMThttp://rollindix.com/blog/window-shade-engineeringAlthough mostly my engineering research, teaching and consulting concerned mechanical design, my PhD research was about heat transfer. At IIT a study I did many years ago for the Window Shade Manufacturers Association investigated the benefits of window shades in controlling heat loss/gain through windows. For that study another professor and I built a carefully insulated room with a typical window in one wall. Direct sunlight was simulated with a bank of Kodak projector bulbs. Measuring flow rate and temperature of airflow circulated showed the reduced heat gain when the shade was pulled down.]]><![CDATA[Pedalong Mechanical Design | Computer Aided Design]]>Fri, 25 Mar 2016 16:39:56 GMThttp://rollindix.com/blog/pedalong-mechanical-design-computer-aided-designBetween cases I work on the Pedalong mechanical design. This pedaled wheelchair for therapy of the elderly and stroke rehab patients plus for general leg strength improvement during hospital stays has held my interest for ten years and absorbed too much time and money. After around 15 prototypes built and many tested, I’ve settled now on a version not needing modification to the wheelchair, but simply coupling to its front frame. Tricycle-like, its single wheel steers and powers the forward motion. Slightly tricky mechanical design allows steering without changing direction of the pedal set.

Completing the CAD (helped by a Spanish graduate student) and building a mockup of the gear system to test durability of cast plastic gears will be complete by summer. Construction of an operating prototype will follow.

Anyone interested in the Pedalong project is invited to contact me at 773-239-3514 or rollin.dix@gmail.com]]>
<![CDATA[Basis of Computer Aided Design]]>Tue, 01 Sep 2015 19:10:28 GMThttp://rollindix.com/blog/basis-of-computer-aided-designComputer Aided Design interfaces are complex and learning to use them is helped by an understanding of their basis. Each “part” is defined within the system by its set of surrounding surfaces. These can either be constructed directly by “boundary representation or B-rep” or by combining “primitive solids” using constructive solid geometry or CSG. Industrial quality software uses both methods for both creating and storing the individual parts.

The usual primitive parts are the rectangular block, the sphere, the cylinder, the torus, the wedge and the cone. Each is defined by a small number of dimensions locating the “vertices” of the solid. Edges connect the vertices and a set of connecting edges then defines a face. The Euler-Poincare formula:

v-e+f-h=2(b-p) must be satisfied by every “part.” Here, v=vertices, e=edges, f=faces, h=number of hole-loops, b=number of bodies (usually 1) and p=passages (through holes). A sphere has a pole (one vertex), one face and is one body, and h=e=p=0. 1-0+1-0=2(1-0) so the equation is satisfied. Using B-reps, one might add an equator dividing the sphere into 2 faces and adding one edge. This is termed an “Euler operation” and 1-1+2-0=2(1-0) is satisfied so the operation is “legal.” Drill a hole through the sphere (avoiding the pole vertex) to add one face, three edges, two vertices, two hole-loops and one passage. 3-3+2-2=2(1-1) is still satisfied. Now you can move the vertices around and bend the edges to make most any shape needed.

Let’s go back to the primitives and consider combining two of them. This Constructive Solid Geometry (CSG) method is the other important tool in CAD that you must understand. In drilling the hole we use “Feature-based Modeling” but the CAD system simply subtracts a cylinder from the sphere’s volume. The system could do the calculations to find the locations of all the new vertices and shapes of the edges and store them (B-rep). Alternatively, the system could just store the location of the cylinder and that it is to be subtracted from the sphere. The usual term is “difference” for the material which is in the sphere, but not in the hole. The other “Boolean operations” are “union” for the material in either of two primitives, and “Intersection” for the material in both of two primitive objects. In AUTODESK Inventor the sequence of Boolean operations (the CSG “tree”) is stored and displayed in the “browser” on the left side of the objects being displayed on the screen. The user can then select geometry by pointing to it on the display or in the tree.

<![CDATA[Early Career Experience]]>Mon, 17 Aug 2015 14:35:54 GMThttp://rollindix.com/blog/early-career-experienceEarly in my career as an expert mechanical engineering witness I was retained by Popeil, Inc. in a patent infringement suit against Sunbeam et al.  The patent covered a steam heated hair curler system and Popeil’s patent contained temperatures measured on the curlers during their use.    I paid several women to operate the Sunbeam unit as directed with thermocouples mounted on the plastic curlers.

My expert report contained plots of these measured temperatures.  The judge in the case found the patent was 1) invalid and 2) not infringed. 

Invalidity was based on “published prior art” - a Japanese-language user instruction sheet connected with marketing of a “steam heated hair curler” on one of the smaller islands of Japan. Non-infringement was based on the temperatures I reported being lower than those contained in the Popeil patent.  I had apparently not conducted my tests in the same manner as the Popeil engineer who supplied the data for the patent.  He must have been careful to open and close the curler box rapidly plus allow time for the curlers to reach a high temperature before taking out the next one.  I had allowed the women to proceed as they liked.

The lesson I learned was that the data supplied by an expert should support the arguments made.  I’m sure a completely valid test agreeing with the patent would have resulted from more careful reading of the patent procedures.

<![CDATA[July Update: CADCAM Information]]>Wed, 22 Jul 2015 16:34:01 GMThttp://rollindix.com/blog/july-update-cadcam-informationThis month I’ve been learning features of the 2016 Autodesk Inventor software from SDC Publication’s various manuals. Four different guides cover basic step-by-step introduction up to advanced use with part and assembly design including sheet metal. Prices are quite moderate.

Parametric 3D modeling has become an extremely powerful design tool in the 35 years I’ve been teaching and using it. Motion simulation, stress analysis, mold design, CNC machining path generation, detailed manufacturing drawings, and complex “sculptured” surfaces are just some of the capabilities. Tables of data for materials and different CNC machines are included in the application.

Starting August 26th, I’ll be teaching many of these concepts in my CADCAM course at Illinois Institute of Technology. I’ll also be using an Autodesk viewer to examine drawings produced by others in my professional consulting.]]>
<![CDATA[May Activity]]>Wed, 24 Jun 2015 20:36:25 GMThttp://rollindix.com/blog/may-activityThis past month I spent many hours helping a friend with his mechanical design patent application. My impression is that patent examiners are looking for ways to reject applications and great care is required to satisfy their detailed demands at each stage of the rejection and reply process. I now have roughly fifty years of experience serving as expert witness in patent and trade mark litigation in in Federal courts around the Midwest. Also this month a law firm which I assisted in a personal injury defense case notified me that they were successful in mediation.

On May 27 my wife and I started a European vacation which included three days in England, two days in Paris, and nearly a week in Normandy. The D-Day tour was conducted by two French guides with excellent knowledge of the details of the invasion. The US National WWII Museum in New Orleans offered the trip at quite reasonable cost, and I strongly recommend it.

Please contact me at 773-239-3514 if you would like more information on these matters or on references who can describe services I have rendered in the past.