Showing posts with label Surface Control Points. Show all posts
Showing posts with label Surface Control Points. Show all posts

Castle bones may belong to knight


Archaeologists believe that bones discovered at Stirling Castle may have belonged to a knight killed in battle or during a siege in the early 1400s.

It is thought that despite the warrior's relatively young age of about 25, he may have suffered several serious wounds from earlier fights.

Researchers thinks it is also possible he may have been living for some time with a large arrowhead in his chest.

The bones were discovered in a chapel at the castle in 1997.

They were excavated when archaeologists were working in an area of the castle which turned out to be the site of a lost medieval royal chapel.

Peter Yeoman, from Historic Scotland, said because the man was buried at the heart of a royal castle, it was indicative he was a person of prestige, possibly a knight.


"His legs were formed in a way that was consistent with spending a lot of time on horseback"

Peter Yeoman
Historic Scotland


Some research was carried out on the skeleton at the time of its discovery, but a lack of technology meant it was difficult to assess the remains in more detail.

Since then scientists have been able to perform laser scanning which revealed the wounds.

Bone regrowth around a dent in the front of the skull suggested the man had recovered from a severe blow, possibly from an axe.

The warrior had also lost a number of teeth - perhaps from a blow, or a fall from a horse.

The fatal wound, however, occurred when something, possibly a sword, sliced through his nose and jaw.

Mr Yeoman said: "We know little about this burial area but the evidence suggests it was sometimes used during extreme circumstances, for example to bury the dead during a siege.


The body was buried at the heart of the royal castle
"However, by using modern analysis techniques we have started to discover quite remarkable information about this man.

"It appears he died in his mid-20s after a short and violent life.

"His legs were formed in a way that was consistent with spending a lot of time on horseback, and the upper body points to someone who was well-muscled, perhaps due to extensive training with medieval weapons."

A large, tanged arrowhead was found in skeleton and appears to have struck through the back or under the arm.

Crystalised matter attached to the arrowhead may have been from flies or other insect larvae and could have been from clothing the arrow forced into the wound.

Gordon Ewart, of Kirkdale Archaeology, who carried out the excavation and some of the research for Historic Scotland, said: "This is a remarkable and important set of discoveries.

"There were a series of wounds, including a dent in the skull from a sword or axe, where bone had regrown, showing that he had recovered.

"At first we had thought the arrow wound had been fatal but it now seems he had survived it and may have had his chest bound up."

War hammer

Little is known about who the man was or where he came from.

Further study is planned on tooth enamel and bone samples which may shed light on his origins.

His body appeared to have been buried in the same grave as a small boy of one to three years old.

Archaeologists cannot be certain that the two were linked but radiocarbon dating suggests both date from the early 15th Century, and there was no evidence of one grave having been cut through the other.

They were part of a group of 12 skeletons, some highly fragmentary, which were discovered.

Among them was a female, probably buried some time in the 13th Century, who had two neat, square holes through her skull which were consistent with blows from a war hammer.

Hexagon Metrology Acquires 3D Software Company

Software Package and Technology Will Enhance 3D Point Cloud Offering

North Kingstown, Rhode Island. January 21, 2009. Hexagon Metrology (London, UK) has announced the acquisition of Technodigit SARL, (Lyon, France), developer of 3DReshaper® software, a software package designed for 3D point cloud and 3D mesh manipulation for reverse engineering, rapid prototyping, product design and industrial inspection. 3DReshaper brings powerful capabilities to the organization and manipulation of the millions of data points created with high speed laser scanning systems such as Hexagon Metrology's ScanShark laser probe, and the Leica T-Scan.

Ken Woodbine, president of Wilcox Associates, the Hexagon Metrology software development group and publisher of PC-DMIS® measurement software, said: "The great promise of laser scanning in industrial measuring applications has always been the enormous amounts of high density data that is collected. However, working with the vast amount of 3D data points that you can now collect in a matter of a few seconds can be a challenge. The file sizes are enormous, and in raw form, the data isn't necessarily organized in a way that's useful. That's where the software comes in. The 3DReshaper Application is a fully-realized 3D package on its own, with powerful features like the ability to import point clouds of unlimited size, mesh shaping and editing and 3D surface comparison for inspection. Many customers have been asking us for these kinds of capabilities as they push further into the requirement to characterize free-form surfaces. Customers in the aerospace, medical, dental, surveying, automotive, power generation and die & mold markets will appreciate the wide variety of capabilities that 3DReshaper brings to the table."

"In the short run, the acquisition of Technodigit will enhance our existing portfolio of software solutions dedicated to point cloud acquisition and manipulation. 3DReshaper already has existing interfaces to certain ROMER portable arm packages, as well as compatibility with Leica Geosystems products, said Woodbine. "The longer view is that the core technologies and algorithms can be selectively incorporated into the PC-DMIS engine to create greater flexibility and functionality in our core software package, which is the de-facto standard software for dimensional inspection at many of our worldwide customers."

Pascal Lefebvre-Albaret, president of Technodigit said: "Hexagon Metrology companies have been good customers for us for many years. Gradually, this relationship has transformed into a partnership and ultimately we were asked to join the Hexagon Metrology family. We are very proud to be part of the world's leading metrology group, with the ability to offer our advanced technology as part of Hexagon's portfolio of software solutions."

The acquisition is effective immediately, and the Technodigit development team will join the Hexagon Metrology software development group, which employs more than 100 in-house developers worldwide.

About Technodigit

Technodigit is the software developer of the 3DReshaper® package which is distributed around the world through resellers and integrators. 3DReshaper software takes 3D data from scanning devices and allows point cloud processing, surface reconstruction, and geometric shape extraction. The software is used in many applications including custom medical and dental appliance manufacturing, land surveying and topography, architecture and cultural heritage conservation, and CAD-CAM applications for industrial markets. A software development kit (SDK) is available for integrators who wish to apply a library of C++ functions to create their own custom applications using the 3DReshaper platform. The company may be found online at www.Technodigit.com.

About Hexagon Metrology

Hexagon Metrology serves the high precision measurement and inspection needs of worldwide manufacturers with its extensive line of metrology hardware, software, accessories, and customer services. The company's name-brand portfolio of quality assurance products include Brown & Sharpe, CogniTens, Leica Geosystems, ROMER, Sheffield, PC-DMIS, DEA, Leitz, and TESA. Hexagon Metrology has an unrivaled installed base of more than 1.5 million handheld, stationary and portable measurement devices, and over 30,000 seats of PC-DMIS metrology software.

The company is a subsidiary of Hexagon AB (Nacka Strand, Sweden), a publicly-traded company (OMX Nordic: HEXA B). The Hexagon group consists of about 8,000 employees located in more than 30 countries.

Delcam’s PowerINSPECT gives a clear competitive advantage

Rayco uses PowerINSPECT to ensure a high-quality product for its customers
Investing in a Romer CimCore portable coordinate measuring arm with Delcam’s PowerINSPECT inspection software has proved to be a big time-saver for Rayco Manufacturing, Inc. "It saves us many hours compared to the manual way most fabrication shops check their work,” said Roger Timmons, Quality Assurance Engineer, "and we get more information about our production faster, so we can make adjustments quickly and accurately. That’s a clear competitive advantage for us.”
Rayco Manufacturing, based in Wooster, Ohio, was established in 1978 to build equipment for the tree and landscape industry. Most of the work at the company is cutting and welding steel to form the structures of the machines. As Rayco grew and its product ranges expanded, the company decided that it needed to further improve the consistency of its steel fabrications and assure their quality from the first laser cut through to the completed fabrication.
An important advantage of PowerINSPECT for Mr. Timmons was that the software has a simple user interface which is intuitive and easy to use. "The learning curve was very short, which let us get the most from the measuring arm in the shortest possible time,” he commented. "I also like being able to import our CAD models directly into PowerINSPECT and overlay what we measure. This reveals immediately where any discrepancies may be.”
"Five minutes with PowerINSPECT saves an hour out on the assembly floor,” Mr. Timmons claimed. "We can make adjustments before the components get into the assembly flow.” For example, the software showed that the run-out on some of the feed wheels used on its chippers was not acceptable. Detecting the situation prior to assembly saved the one and a half to two hours it would take to remove and replace an inaccurate feed wheel.
In another example, the frame for one of its machines was exhibiting a twist during assembly. According to Mr. Timmons, "We measured it during welding and found that the fixture needed correction. We also use the system for troubleshooting out on the assembly floor to determine why a part may not be fitting perfectly, so future parts can be corrected before they go to assembly. We can do this in about 10 minutes, a time saving of up to 1,000% compared to any manual method.”
Rayco did not have a dedicated quality department until about three years ago. "Today, we inspect critical parts and all fixtures on a regular basis,” Mr. Timmons said. "This helps us put out a high-quality, high-performing product for our customers.”

CAD Modeling The Basics

By Mark Boucher, CMM Quarterly

I want to cover some basics about CAD models that might help us understand what is happening with some model features when you program from a CAD model using your coordinate measuring machine. By understanding surfaces we can better evaluate any anomalies we may encounter when we import a model into our CAD base CMM software.
There are several model types and we will cover two of the most common ones you would come across today, solid models and surface models. To be more accurate, they are parametric models and freeform surface models.

Parametric Models

Parametric models are created from features that are defined by parameters, or dimensions. These dimensions can be changed and the feature moves with the change. Prior to parametric modeling if a change was made then the feature was recreated, extruded, trimmed, etc…, in the new position and the old feature was deleted. Parametric modeling maintains the relationship of part creation, assembly, to output of the blueprint and a change anywhere along that process will update the model at every level.

Parametric models are referred to as a solid model, as opposed to a wireframe model. A wireframe model is made up of lines that represent the part but have no surfaces on them and makes 3d viewing somewhat tedious.

Parametric modeling revolutionized the CAD industry and allowed more affordable CAD software to become available to anyone. You can now pick up parametric CAD programming software up at your local Best Buy right off the shelf.

Freeform Surface Models

The second model type I want to cover is the surface model. With surface models curves are used to define the surface area and surfaces are applied between the curves then they are trimmed and merged, to make a solid. The problem with this method is to make sure all the voids between the surfaces are filled in. The surface definition changes as the need requires. Let’s say, you have a plane that requires basically four lines to define the boundary of the plane. A chamfer merging into a radius requires a greater amount of defining to create this type of feature. While creating the surfaces you may end up with a small void as you try to fill in the feature. Point placement from your CMM program will be dependant on where it sees the plane boundaries and a void will not be inclusive in this plane so the boundaries are redefined not giving you a true representation of the surface. In parametric modeling these types of transitions are automatically resolved.Some CMM CAD based software have a ‘healing’ or ‘repair’ functionality that will mend some of these errors. It is always advisable to use healing when using this type of model. If your software does not include this functionality there are third party softwares that do the job for you.SurfacesCreation of surfaces begins with a spline, aka curve. Splines are single lines that make up the shape of the surface. Imagine points that make up the shape of your surface and spline will fit through these points. These splines are then used to create the surface through a method known as ‘swept’ (using the curves as a guide rail) or meshed (lofted) through. A ‘swept’ surface follows the shape of the curve line. If you had a helical curve the swept surface will follow that helical shape as it extrudes the surface.

If your engineering department does any sort of reverse engineering they will ask for a series of curve files that they can import into their CAD system. The curve files are then used to ‘mesh’ or ‘loft’ the surfaces. The density or frequency of the curve lines along the surface will depend on the complexity of the surface being scanned. For flat planes only several are needed but scanning the chamfer to radius transition we discussed before would require a greater amount of curves to define the feature.

Another method is direct creation of the surface with manipulation of the surface control points. Points are created along the curves that can be grabbed and drawn in any direction to create a new surface shape. This inherently will create new surfaces to fit the new configuration.

It is important to note that the majority of CMM software in the market today do not have true CAD functionality and thus do not have the ability to manipulate surfaces as described above but it is important to know what is happening during model creation.


This article is copyrighted. For permission to reprint this article please contact Mark Boucher at info@cmmquarterly.com