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Dassault Systèmes Pledges a Virtual Twin of the Human Body

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Dassault Systèmes plans to make a virtual twin of the human body in the coming years, says Bernard Charlès, the company’s vice chairman and chief executive officer. The plan fits in with the company’s overall vision to help cure patients and help them live longer.

“In 1989, we created the first virtual twin of a giant airplane, the Boeing 777,” Charlès says. “Today we’re capable of applying the knowledge and know-how we acquired in the non-organic world to the living world, extending our focus from things to life. The virtual twin experience of the human body will enable us to invent new ways of representing life by understanding and representing the invisible and make a lasting contribution to  benefit all.”

A virtual twin experience of the human body created with the engineering software company’s 3DExperience platform will integrate modeling, simulation, information intelligence and collaboration, he says. It brings together biosciences, material sciences and information sciences to project the data from an object into a complete living virtual model that can be fully configured and simulated.

“By combining art, science and technology, it makes it possible to understand the invisible to represent the visible. Industry, researchers, physicians and even patients can visualize, test, understand and predict what cannot be seen—from the way drugs affect a disease to surgical outcomes—before a patient is treated,” Charlès adds.

To achieve this strategy, Dassault Systèmes will focus on developing its leadership in life sciences and healthcare. It will also work to further develop leadership in two other sectors: manufacturing industries and infrastructure and cities, he says.

These sectors share similar development processes and sustainability needs in their efforts to improve quality of life, whether through more affordable and precise therapies, optimized infrastructures, or better use of the environment, Charlès says.

At Dassault Systèmes 3DExperience World event held earlier this month in Nashville, Mike Schultz, a Paralympic gold and silver medalist, spoke about his use of SolidWorks computer-aided design modeling tools to continue perfecting the design of a prosthetic leg, knee, and foot. He originally designed the prosthetic leg after he lost his leg above the knee in a 2008 snowmobile racing accident.

He went on to found BioDapt, a company that designs and manufactures high-performance, lower-limb prosthetic components used for action sports and

BioDapt makes high-performance, lower-limb prosthetic components used for action sports and similar activities.

similar activities. The goal is to manufacture the highest quality and highly versatile components that allow amputees to participate in sports and activities. This equipment can be and is used by many elite adaptive athletes as well as by the average person who wants to get out and be active, Schultz says.

Schultz is the creator of the Moto Knee and the Versa Foot.

“I wanted to get back to doing the activities I loved—mainly motocross and snowmobile racing—but I soon found there was nothing that would really allow me to ride the way I did before my amputation,” he says.

“With my knowledge and experience of fabrication, the experience of tuning suspension on my race equipment and my unwillingness to compromise I set out to create what I needed. After nearly two years of development I have come up with a knee unit that is versatile enough to handle many different action sports and has helped me win multiple ESPN X Games medals ain the adaptive motocross and snocross events,”  Schultz adds.

Matt Carney, a biomechatronics graduate student at the Massachusetts Institute of Technology also spoke at 3DExperience World. He is working to connect cybernetic interfaces to the human body; enabling direct control of robotics limbs. Carney says he is focused on the future of prosthetics and on eventually creating full biological capabilities in artificial limbs.

The many uses for reverse engineering

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Some look unfavorably at reverse engineering as a way to steal secrets from competitors. But the science has a number of important uses, especially in forensic engineering.

Jean Thilmany, Senior Editor

In legal cases, forensic engineers are commonly called upon to present evidence about how or why a part or a process failed. The forensic engineer often relies upon reverse engineering to understand how a part was created.

“By stepping back through the transformation stages, the engineer is in a better position to determine the most probable or expected points of failure within a component or system,” says Colin Gagg, an independent forensics engineering consultant in Milton Keynes, England.
Complicated—and even straightforward—systems can malfunction dramatically and tragically in seconds. When the malfunction becomes the subject of a legal case, Gagg is often asked to investigate.

“To recognize how a component or system failed, the engineer must understand how it worked and was manufactured in the first place,” Gagg says. “By stepping back through the transformation stages, they’ll be in a better position to determine the most probable or expected points of failure within a component or system.”

So, add “forensics engineering” to the ever-growing list of applications for reverse engineering. Engineering companies have also found the process can help reduce costs by refining already existing parts to a new process.

“It’s my view that a good forensic engineer will glean relevant information through meticulous investigation and by taking a reverse-engineering approach,” Gagg says.

“The same could be said of engineers charged with creating parts in the first place,” Gagg says. “Any engineer should aim to train himself to become a failure detective.”

3D scanners, such as this Faro Arm from Faro, have become invaluable tools for capturing the geometry of an object and re-creating it in software. These scanners fire a beam of laser light that reflects back from the object it hits, collecting data on the object’s geometry. The collected data becomes a “point cloud” that is exported to software, and used to create a digital image and a CAD model.

Stuart Brown, managing principal at Veryst Engineering, Needham Heights, Mass., offers an example from his company’s own case file.

When the brakes of a Schindler elevator in a 23-story Tokyo condominium failed in 2006, trapping and killing a teenage boy, prosecutors in the resulting lawsuit laid out a number of scenarios under which the failure could have happened. But they weren’t able to home in on any one scenario, Brown says.

Forensic engineers at Veryst were able to show—using software to simulate and analyze the scenarios—that the brakes could have failed quickly, indeed within a matter of hours. Their analysis helped to clear a maintenance official, who, prosecutors claimed, should have detected signs during a November 2004 check that the brakes could fail.

At issue in the case was determining when excessive abrasion occurred in brake parts that are believed to have caused the accident, Brown says. In September 2015, a Tokyo District Court acquitted Ryuichi Harada, a former Schindler employee in charge of maintenance. The court said that “no objective evidence” existed to show that the brake abnormality had occurred by November 2004 when Harada checked the elevator, according to the Japan News.

The judge in the case found three people at SEC Elevator Co. guilty, however. SEC took over Schindler’s maintenance work in April 2006. The judge said they overlooked the abnormality and “neglected their duty to establish an appropriate system for checks and maintenance,” according to the news source.

The rate at which the brake linings could wear, leading to the accident, was critical to analyze and depict in the case, Brown says. For example, police investigators had measured brake wear. Veryst forensic engineers entered those numbers and also input from a variety of other factors into their analysis software: brake drum temperature, changes in the expansion and contraction in brake drum size, the usage cycle of the elevator over a period of days, and changes in the brake system’s solenoid force and solenoid position as it wore, Brown says.
“Bringing in all these factors, we showed that once the brake temperature got high enough, the wear could have occurred within 30 hours,” he says. The forensic engineering analysis showed it didn’t take weeks or months or years for the wearing to occur. Failure didn’t happen slowly over time, but was caused by a “cascading effect which could tragically happen over short period of time,” Brown says.

Bringing it back

Reverse engineering is commonly defined as the act of reproducing an already-created product by examining its construction and composition. Designers scan the part with a specialized scanner capable of loading design coordinates into a software system.

The reverse-engineering process needs hardware and software that work together. The hardware is used to measure an object, and the software reconstructs it as a 3D model. The physical object can be measured using 3D scanning technologies like a coordinate measuring machine, laser scanner, structured light digitizer, or computed tomography, says Braxton Carter, chief technology officer at ReverseEngineering.com, a software developer in La Jolla, CA.

Software, like Geomagic from 3D Systems, helps engineers capture the data points of parts without CAD drawings. Engineers can use this software to exactly recreate the part as originally built or add dimensional features to the CAD model to meet design specifications.

3D scanners have become invaluable across a range of industries that need to capture the geometry of an object and re-create it in software. To bring those real-world dimensions into the computer, 3D scanners fire a beam of laser light that reflects back from the object it hits, then measure the amount of time it takes for the light to return and calculate how far away the object is. The scanner continues to rotate, measuring the object completely. The resulting “point cloud” is exported to software, and the dots are connected to create the digital image and a CAD model.

It’s true that reverse engineering is most commonly thought of as being used to determine how to recreate a no-longer-in-production part, says Johnson Shiue, a software quality assurance technology leader at Autodesk.

As he puts it, “Let’s say you have some partial data. How do you make something from it?”

“Whether you’re a designer doing benchmarking or are retrofitting an older design, you need to work with incomplete data,” Shiue says. “Digesting the incomplete data and changing it into useful model geometry is both a science and an art.”

Or, the goal could be to determine out how a particular part or piece of equipment works and improve upon it, he says. As the hardware and software used for the technique have become more affordable, small engineering companies can speed development and cut production costs by integrating existing parts with their CAD program, Carter says.

Take Excel Foundry & Machine, of Pekin, Ill., which makes replacement parts for nearly every type of mining and rock-crushing machine. When the company sought to expand about three years ago, executives faced a dilemma, says Chris DeWitt, a former senior design engineer at the company.

“We needed to venture off into more complex parts and systems, and in doing so, it’s rather difficult to get all the dimensions you need with the old hand tools,” DeWitt says.
The engineers knew the coordinate measuring machine alone wouldn’t be enough. DeWitt and his colleagues knew the coordinate measuring machine (CMM) needed software that could deliver measurement data into the company’s CAD system.

The company installed desktop reverse engineering software from Reverseengineering.com and purchased a separate CMM.

The new system allowed the company to create more complex replacement parts than in years past, Dewitt says. Excel Foundry engineers estimate that measuring parts and creating replacements without the hardware and software package would take about four times longer than it does now.

Reverse engineering is also making its way into the maintenance repair overhaul (MRO) field, Carter adds. The field is seeing a new focus in using 3D reverse engineering to employ new and developing technologies such as augmented reality (AR) to help improve the accuracy and turnaround time in replacing unique or highly specialized parts in machinery.

Geomagic, which makes, scan-to-CAD software, details a project where one of its customers was developing a specialized, autonomous-driving, light-duty vehicle.

To speed time-to-market, the customer selected and combined a range of components and systems from vehicles on the market today to complete a working prototype. In this process, the customer’s engineers found a specific steering knuckle for the project, so they digitized and captured the design, then further refined and modified it within the CAD system. It then manufactured the knuckle from a lightweight material.

“Typically, customers will follow either an as-built or design-intent modeling method,” according to Geomagic. That means customers will look to exactly recreate the part as originally built or will add dimensional features to the CAD model to meet design specifications.

For the steering knuckle, the customer used a hybrid modeling approach that combed both concepts to deliver a CAD solid model with both dimensioned features and accurate NURBs surfaces. With the strategy, the customer had a model ready in less than two hours, and then transferred the model to SolidWorks as a feature-based CAD design.

It planned to then create the steering knuckles using 3D printing.

To find manufacturing methods

Gagg also uses reverse engineering to discover how a manufacturing process may not have performed as needed.

An example comes from his book, Forensic Materials Engineering: Case Studies, co-authored, with Peter Rhys Lewis and Ken Reynolds (CRC Press, 2003). This case began when a dock worker noticed a split in the end panel of a loaded 33-foot-long container being lifted from a ship. The container showed no other obvious signs of external damage, and the piece of machinery it held was still anchored inside.

Shortly after that first split was found, workers at other ports noticed similar failures in the same type of freight container. Costs quickly escalated as the damaged containers had to be either disposed of or repaired. Machines had to be loaded into other containers, and empty containers needed to be shipped to the ports with damaged containers.

Investigators found that all the containers had been made at the same factory during a two-month period. On each one, the riveted seam between the two end panels in the side of the container had split open from bottom to top. All the containers had split in the same way, and all had been carrying heavy machinery rather than bulky loads evenly distributed throughout their length.

A mechanical engineer found nothing wrong with the original design or with the construction of the containers.

Forensic reverse engineers were called in to track each part and how it had been manufactured. They determined that the container’s side panels were sheets of aluminum alloy, riveted to each other and to the frame along vertical lap joints. All the failures involved the unzipping of the vertical lap joint between the first and second sheets from the end of the container.

As the aluminum sheets were deemed innocent, their focus turned to the rivets. Although microscopic examination found no internal fault, wear, or corrosion, investigators found that if one rivet near the end of a seam failed, it would throw the extra load onto its neighbors, which could overstress them, causing all the rivets to unzip. After looking at the specification for the rivets on the engineering drawing, the Forensic reverse engineers performed a hardness test on the failed rivets. The tests indicated that the rivets were well below the strength indicated on the drawing.

A mechanical engineer then found that a batch of containers was produced with rivets that had been set without being first solution treated, as specified on the drawing. It was subsequently discovered that a single employee at the container factory had omitted the solution heat treatment.

Case solved. And other case made for reverse engineering.

Dassault Systèmes Expands 3DExperience Works and Partners with Xometry

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Dassault Systèmes announced three new 3DExperience Works commercial software offerings: standard, professional, and premium, at the company’s 3DExperience World conference this week. Gian Paolo Bassi, Dassault Systèmes company’s chief executive officer announced the expansion.

The engineering software maker also announced a new partnership with Xometry, a company that makes an on-demand manufacturing software, including additive manufacturing. The partnership will give SolidWorks and Catia users swift access manufacturing price quotes via the Xometry software. They’ll be able to get those quotes right on their design screen without the need to switch between software systems, Bassi says.

Xometry is Dassault Systèmes’ Make Marketplace’s first prime partner—a new category of partner that provides best-in-class buying experiences to users of Make Marketplace, Dassault Systèmes’ on-demand manufacturing service, Bassi says.

The 3DExperience Works expansion now offers standard, professional and versions and feature SolidWorks computer-aided design standard, professional and premium applications installed from, licensed from, and updated in the 3DExperience platform using data stored in the platform.

The connection means SolidWorks users can still use the SolidWorks desktop application they’re familiar with, while they also get the benefits of the 3DExperience digital platform. These include improved collaboration, embedded data management, automatic software updates, and access to current project data. In other words, SolidWorks users will have the CAD software and the platform access in one place on their desktop.

SolidWorks users to select from dozens of other 3DExperience Works applications to the ones they need for their tasks.

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The scaled software also includes 3D Creator and 3D Sculptor, design applications that run in any browser.

“Customers want to do more than just design. They want to have a life-like experience of the products they make,” Bassi says. “This requires better design, simulation, governance, management, and manufacturing and—most important—collaboration within the entire value chain.

“We want to provide customers with more options that make sense for their business. That’s why we’ve made it easy for them to take advantage of and explore 3Dexperience Works platform,” he adds. “On the platform, everything and everyone involved in the concept, design, simulate, manufacture, sales, and service processes are connected and integrated in one continuous loop.”

SolidWorks customers can continue to buy the standalone SolidWorks desktop version. Dassault Systèmes also plans similar releases for its education and startups packages.

The Xometry partnership will allow engineers to get Xometry price quotes on their screen, in the context of their design, and click to have it manufactured while—at the same time—having the option to get instant or manual quotes from other Make Marketplace suppliers.

“Customers can order high-quality additive manufacturing or CNC machining parts in one click, at the right price, with Xometry’s instant quoting capabilities,” says Sébastien Massart, head of corporate strategy at Dassault Systèmes. “This is all part of our vision to reduce the friction that customers face going from design to manufacturing.”

The new prime partnership category in which Xometry is placed recognizes qualified service providers that have industrial-grade quality certifications and production capacities, he says. Dassault Systèmes plans to add other prime partners to its 3DExperience Marketplace ecosystem.

Dassault Systèmes’ 3DEXPERIENCE World 2020

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Dassault Systèmes announced 3DEXPERIENCE World 2020 February 9-12 at Music City Center in Nashville, Tenn., where 6,000 designers, engineers, makers, entrepreneurs, students and business leaders from all industries can learn, collaborate, innovate and experience the latest 3D technologies driving the Industry Renaissance.

The inaugural 3DEXPERIENCE World builds on the 20-year legacy of Dassault Systèmes’ SOLIDWORKS World events dedicated to the 3D design and engineering community. With a larger selection of learning opportunities, presentations, products, new technologies and experts, attendees can develop and expand their skills to become more inventive, efficient and responsive across the different processes involved in the creation of new experiences that transform how the world thinks, works and lives.

In particular, 3DEXPERIENCE World 2020 will introduce SOLIDWORKS users to new strategies for business innovation through discussions and demonstrations of 3DEXPERIENCE WORKS, Dassault Systèmes’ portfolio of digital applications on the 3DEXPERIENCE platform for collaborative design to manufacturing.

Other event highlights include:

• Keynote presentation from industry thought leader Charles Adler, co-founder and former head of design, Kickstarter.com, Kickstarter.
• Customers, innovators and partners on the cutting edge of design including Sam Rogers, additive design lead and jet suit pilot, Gravity Industries; Mikael Kajbring, CTO, Awake, makers of the Awake electric surfboard; Mike Schultz, founder of performance prosthetic manufacturer, BioDapt; Matt Carney of the MIT Media Lab Biomechatronics group; and more.
• More than 350 technical sessions in the form of lecture-style breakouts, hands-on workshops, and expert-led panel discussions on the latest innovations in 3D design, data management, simulation and manufacturing.
• The 3DEXPERIENCE playground, a dedicated space to discover new technologies, tools and applications from more than 100 partners, experience virtual and augmented reality innovations, participate in hackathon and Model Mania challenges, and see the impact of 3D technology on education and startups.

“We’re continuing the long legacy we’ve built with this community. 3DEXPERIENCE World, like last year’s SOLIDWORKS World, is a unique gathering where 3D enthusiasts can think creatively, network, and be inspired by future technological advances,” said Gian Paolo Bassi, CEO, SOLIDWORKS, Dassault Systèmes. “Past SOLIDWORKS World attendees will still find everything they’ve come to expect each year, but also applications and uses of 3D technology they didn’t expect. First-time attendees will find a large selection of solutions and experts to connect with. We aim to showcase all the possibilities within the vast Dassault Systèmes ecosystem that help our user community to go about their work and successfully achieve their ambitions.”

Dassault Systèmes
www.3dexperienceworld.com

New Tool Bridges 2D and 3D Graphics

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Canvas GFX, Inc, a provider of technical illustration software has released a new product, Canvas X3 CADComposer, which it describes as a bridge between three-dimensional and two-dimensional illustration. It enhances the core Canvas X3 software with the capability to import and edit 3D CAD files. No need to switch between 2D and 3D software.

The CADComposer now provides an integrated design environment so users can combine all 2D and 3D graphical elements and apply high-end effects within a single document, said Patricia Hume, chief executive officer of Canvas GFX, which makes the tool.

With the tool, technical illustrators can import 40 different 3D file types into the Canvas environment, then position, explode, enhance, and annotate these models for use in a variety of 2D assets. Canvas X3 imports all metadata attached to each model, allowing illustrators to document and reference individual model parts for a range of outputs, including a bill of materials.

By giving illustrators the ability to handle 3D models and metadata directly, Canvas X3 CADComposer frees CAD engineers from having to supply many model views for downstream use, which saves them time and allows them to prioritize other activity. It gives technical illustrators and graphic designers the capability to manipulate 3D CAD models without the need for expensive CAD software.

This allows users to use their source CAD files to produce assembly diagrams, maintenance manuals, repair guides, product sheets, marketing material, and more.

The tool can import a great array of 3D CAD, vector, and raster file formats and export many image and vector formats. Users can work with 0.035-micron accuracy. They can show, hide, or ghost any part in their assembly to better focus the viewer. They can also change colors of assemblies to highlight parts within them.

CAD objects can be edited and re-edited as many times as needed. Users can update documents with new versions or changed views by double-clicking an object. Any rendering can be undone.

They can also automatically label parts in their illustration with CAD metadata to quickly create a bill of materials from CAD data that lists all the parts of the assembly. They can intuitively move parts along their axes for exploded views to help viewers understand how multiple components interconnect.

This is the first Canvas product to build on the firm’s partnership with Dassault Systèmes’s subsidiary Spatial.

Canvas GFX looked to Spatial Corp., a provider of 3D software development toolkits for design, manufacturing, and engineering solutions, for enabling technology for 3D import and model visualization. The engineering team at Canvas GFX selected 3D InterOp, a 3D CAD data translation software development toolkit from Spatial, Hume said.

“3D InterOp enables Canvas X3 users to work with imported 3D data as easily as if it were created natively in the Canvas GFX tool. The result is improved workflow efficiency and enhanced user experience,” added said Vivekan Iyengar, vice president of research and development at Spatial.

Canvas GFX and Spatial Corp announced their partnership in May 2019.

 

 

Implicit modelling for complex geometry

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Implicit modelling is enormously powerful and offers huge potential for engineering design. It is currently ready to apply in specific modelling tasks involving complex geometry. It is not yet clear whether it will be possible to fully implement it within the familiar parametric design environment, with constraint-based sketches used to define geometry. If not, it may remain a specialized tool.

Dr. Jody Muelaner, PhD CEng, MIMechE, Muelaner Engineering Ltd

Additive manufacturing enables the production of highly complex geometries such as repeating lattice-like structures and organic shapes. This design freedom can improve performance in terms of weight, stress, fluid flow and heat transfer. However, modelling, editing and processing complex geometry files is challenging for the established CAD software. Let’s look at how implicit modelling can solve these problems as well as the challenges still remaining to integrate it into the design workflow.

The problem with current CAD software
If you’ve ever tried modelling complex lattices in a typical CAD program, such as SolidWorks, you’ll know this is extremely challenging. When models have large numbers of features, the file sizes and rebuild times increase exponentially. Conventional CAD programs can also have difficulty with apparently quite simple models if they have features such as two fillets that overlap. When high feature counts are combined with these types of challenging geometry, model rebuilds become painfully slow at best and all too often they simply fail.

The problem is the fundamental way that geometry is represented. All the major CAD programs use boundary representations (b-reps) to define solid geometry. B-reps use topology, such as vertices, edges and faces, which are defined by geometry such as points, curves and surfaces. For example, an edge is a bounded region of a curve and a face is a bounded region of a surface.

B-reps work fine for relatively simple geometry. Older CAD programs sometimes used Boolean operations to combine primitive objects such as cubes and spheres. B-reps are much more versatile, allowing profiles to be swept and lofted, solids to be shelled and so forth. However, when features are combined with fillets and blends, or large numbers of features are included, calculating the topology becomes exponentially more demanding on the computer. Many modelling operations involve combining simpler shapes with Boolean and blending operations. B-rep modelling has to calculate all of the new edges that are formed where faces intersect. For objects with planar faces the individual calculations are relatively simple, but the number of intersections increases by approximately the square of the number of faces. For intersections between curved surfaces the edges are complex splines, making the calculations considerably more complex. When faces are close to tangent, things get really difficult.

Another issue with B-reps can be determining which points in the model are inside the boundary – the solid material. The method is to shoot a ray from the point in an arbitrary direction. If the ray passes the boundary an odd number of times then the point is inside the boundary. If the ray passes the boundary an even number of times then the point is outside the boundary. Since floating point arithmetic is used, rounding errors may mistakenly count boundary crossings when the ray is close to the boundary. There are also ambiguities such as when a ray is tangent to a surface or passes through a vertex – it is not clear whether this counts as a boundary crossing, or as two crossings. Because of these issues, additional checks are required to ensure that b-rep modellers are robust. This makes them mathematically inefficient.

The mathematical simplicity of Implicit Modelling
Implicit modelling is a far more efficient way to model geometry. It doesn’t explicitly calculate any edges or vertices. Instead, a single mathematical function of x, y and z is used to describe a 3D solid. Consider the simple example of a cuboid centered on the origin.

A cuboid can be defined by the implicit function. Any point on the boundary gives a function value of zero, negative values are inside, and positive values are outside, which makes the determination of whether a point is inside or outside simple.

This cuboid can be defined by the implicit function:

FA(x, y, z) = max(|x| – 4, |y| – 1, |z| – 1)

Any point on the boundary gives a function value of zero, negative values are inside, and positive values are outside. Determining whether a point is inside or outside is therefore very simple. There is no need to try to count how many times a ray crosses the boundary. Small floating-point errors will give the wrong answer only if the point is infinitesimally close to the boundary.

Performing Boolean operations to combine implicit geometry is also very mathematically simple. Consider two solids being added together in a Boolean union. For a point P to be within the combined solid, at least one of the two implicit functions must evaluate to less than zero. The combined implicit function is, therefore, simply the minimum of the two functions.

Imagine that a sphere, centered on the origin and with a radius of 2, is added to the cuboid.

Performing Boolean operations to combine implicit geometry is also mathematically simple. Consider two solids added together in a Boolean union. For a point P to be within the combined solid, at least one of the two implicit functions must evaluate to less than zero. The combined implicit function is, therefore, simply the minimum of the two functions.

The implicit function for the sphere is:
F(subsetB) (x,y,z) = √(x^2 + y^2+ z^2 ) – 2
The implicit function for the combined solid is simply the minimum of the implicit functions for the two shapes:

FC(x, y, z) = min(FA, FB)

This simplicity of calculating geometry means that complex fillets and blends can be created reliably, and highly complex models rebuilt almost instantly. The below image shows fillets where a lattice joins a ring. The fillets overlap in a way that would probably fail in most CAD systems, but they have been easily created using nTopology implicit modelling software.

Implicit functions can also give a feature’s distance from the boundary.

Distance fields – a powerful feature
Another really useful property of implicit functions is that they actually give the distance from the boundary. A good way to understand this is to simply try some values in the function for a cuboid, used in the example above:

FA(x, y, z) = max(|x| – 4, |y| – 1, |z| – 1)

The smallest value that this function can take is -1. This occurs for points down the centre of the volume. There is no upper limit to the value it can take, since you can travel infinitely far once outside it.

Implicit functions make it easy to calculate a distance field either inside or outside the boundary of any solid geometry. This makes it very easy to perform shell operations and you can even create shells with varying wall thickness.

Implicit functions make it really easy to calculate a distance field either inside or outside the boundary of any solid geometry. This makes it very easy to perform shell operations. It is even possible to create shells with varying wall thickness.

Because implicit geometry is defined as a field, it can be modified by other fields. This enables highly efficient merging between different geometries, to create features similar to fillets. It is even possible to modify a geometry field using some other property, such as a stress field generated from an FEA study. In the below example, nTopology has been used to modify the diameters of beams in a simple diamond lattice, with the diameter increasing as the stress increases. It is also possible to do this with shelled solids, so that the wall thickness depends on stress. This can be a powerful method of optimizing structures that, unlike generative design, works well with cast or injection moulded components, as well as additive manufacturing.

In this example of implicit geometry, the software program nTopology was used to modify the diameters of beams in a simple diamond lattice, with the diameter increasing as the stress increases. It is also possible to do this with shelled solids, so that the wall thickness depends on stress. This can be a powerful method of optimizing structures that, unlike generative design, works well with cast or injection moulded components, as well as additive manufacturing.

Implementation of Implicit Modelling

A number of commercial software companies are offering implicit modelling packages. The field is currently dominated by smaller specialized providers such as nTopology, which has a suit of capabilities for working with complex geometry. Another notable start-up, Gen3D is currently focused on modelling flow paths for applications such as manifolds and heat exchangers such as the one shown below. The big players in the CAD world, such as Autodesk and PTC have started acquiring start-ups in order to gain access to this technology. Autodesk recently announced their Volumetric Kernel for Fusion360 which, it is claimed, will enable implicit modelling to be fully integrated within a parametric design workflow.

A number of commercial software companies are offering implicit modelling packages. One notable start-up, Gen3D, is currently focused on modelling flow paths for applications such as manifolds and heat exchangers.

At the moment, however, it is not possible to work directly with implicit models within any mainstream CAD system. Specialized implicit modelling software is instead focused on creating the complex geometry that conventional CAD struggles with. For example, you might import an initial design from your standard CAD package and then perform operations such as creating complex lattices, shelling complex components or creating intersecting fillets.

The most obvious application is for light weighting structures using lattices for additive manufacturing. However, there are many other potential applications for complex geometry creation such as cast components with complex fillets and variable thickness shells. Many industrial designers are taking advantage of the capabilities to produce decorative grills. Implicit modelling software such as nTopology makes it extremely easy to create these types of geometry.

Stress analysis using Finite Element Analysis (FEA) can also benefit hugely from implicit modelling. One of the most time-consuming parts of analysis can often be cleaning up the geometry created by CAD software. Because b-rep modelling creates edges where any surfaces meet, there can often be thin sliver geometry at intersections and fillets. This can make even relatively simple parts difficult to mesh with high quality elements. Implicit models don’t have any of these issues giving the potential for painless creation of high quality meshes. This can, however, create its own issues as discrete surfaces may be needed to define boundary conditions. B-rep surfaces are therefore sometimes imported from CAD to enable boundaries to be defined.

Gyroids and Triply Periodic Minimal Surfaces
Triply periodic surfaces are an interesting type of geometry that is relatively new to the world of manufacturing, although they have been known to mathematics since the 19th century. These surfaces repeat in each of three dimensions, similar to conventional arrays. However, the arrays of intersections between each element are often problematic, with fillets at each interface quickly making models unmanageable. With triply periodic surfaces, there are smooth transitions between each repeating element, with the entire surface defined by a single implicit function.

Triply periodic surfaces are a type of geometry that is relatively new to manufacturing, although they have been known to mathematics since the 19th century. These surfaces repeat in each of three dimensions, similar to conventional arrays. However, the arrays of intersections between each element are often problematic, with fillets at each interface quickly making models unmanageable. With triply periodic surfaces, there are smooth transitions between each repeating element, with the entire surface defined by a single implicit function.

Within mathematics and the natural sciences, there is particular interest in triply periodic minimal surfaces (TPMS) which are minimal surfaces as well as being triply periodic. This means having zero mean curvature. Although structures used within additive manufacturing may be TPMS’, it is generally not important whether or not they are minimal surfaces.
Because triply periodic surfaces can be defined by a single implicit function, they can easily be combined and blended with other implicitly defined geometry. They can also be modified by other fields so, for example, they adapt to stress, fluid flow or heat transfer requirements. These properties can make them enormously powerful from a modelling perspective. They also have many interesting mechanical properties although understanding these properties is still very much an area of active research.

Robust modelling enables greater reuse
One of the benefits that nTopology is stressing is something they call their notebook. This is a way of recording the process used to create geometry, very much like the feature tree in parametric CAD. Variables can be changed and references to external files updated, before replaying the process. This can enable workflows and best practices for capture, reuse and refinement.

While nTopology’s notebook is conceptually similar to a parametric feature tree, the increased robustness of implicit models should make it more useful. While parametric model templates work well for simple standard parts, they are often unreliable for more complex products. This is often because topology such as vertices and edges are automatically created and assigned ID’s while the geometry is being constructed. When changes are made that affect the way features intersect, especially where fillets are involved, the number of vertices and edges may also change, resulting in different ID’s being assigned. Features that reference this topology therefore lose their references and the model fails. The designer is often faced with a choice between a lengthy debugging process and recreating the model from scratch. Implicit modelling doesn’t depend on these topology references and is therefore unlikely to fail when variables are changed. However, if b-rep geometry is referenced underlying topology may cause workflows to fail because of this dependence.

Thus, implicit modelling is enormously powerful and offers huge potential for engineering design. It is currently ready to apply in specific modelling tasks involving complex geometry with the potential to be fully implemented in the familiar parametric design environment.

Muelaner Engineering Ltd
www.muelaner.com

Create a minimal packaging envelope automatically

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The latest version of the German-French software company CoreTechnologie GmbH (CT) 3D_Evolution Simplifier software includes the Simplifier–a fully automatic calculation of the smallest sphere diameter that surrounds a part or an assembly. With this function, the Simplifier enables a time-saving and automated calculation of optimal packaging.

In addition to the diameter calculation according to DIN EN ISO 8062-1, minimal packaging dimensions can be calculated in the form of a box and output as a CAD model of any major format. The determination of the smallest possible packaging dimensions, i.e. the smallest possible space, is used, for example, to optimize logistics costs and to minimize the cost of materials for packaging individual parts or assemblies with a complex shape. This process can now be carried out automatically in seconds.

The 3D_Evolution Simplifier software is used for fast and automatic data simplification as well as for the conversion of CAD models of all common formats such as Catia, NX, Solidworks, Creo, Inventor, Step, JT and more. The creation of an envelope geometry helps designers work smoothly and quickly with extensive and detailed 3D original data in CAD, VR and simulation systems. In terms of data quality, the tool enables the conversion of perfect solid models through data analysis and correction functions. In addition to protecting the know-how by creating the envelope models, the technology reduces the file size as well as the elements that have to be displayed.

CoreTechnologie
www.coretechnologie.com

Aras licenses platform to ANSYS in strategic OEM deal

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Aras, a platform provider for digital industrial applications, announced a strategic partnership with ANSYS that includes the licensing of the Aras platform technology to enable the next generation of digital engineering practices.

ANSYS will leverage the underlying Aras platform technologies such as configuration management, PDM/PLM interoperability, API integration and add simulation specific capabilities to deliver scalable and configurable products that connect simulation and optimization to the business of engineering.

Organizations are leveraging simulation throughout the product lifecycle, interoperating with their existing PLM, ALM and ERP applications. Additionally, customers must address scale and complexity challenges with data and process management, traceability and availability of simulation results across the lifecycle.

ANSYS is leveraging Aras’ resilient platform services combined with its proven simulation domain expertise and technology for new product offerings to improve productivity and maximize business value from simulation investments. ANSYS will deliver commercial offerings for simulation process and data management, process integration, design optimization and simulation-driven data science.

ANSYS, Inc.
www.ansys.com

Aras
www.aras.com

Multiphysics for IronCAD 2020 released

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IronCAD, a leading provider of design productivity solutions, announced the immediate availability of the latest version of its fully integrated Multiphysics for IronCAD (MPIC).

Since the unveiling of Multiphysics for IronCAD, the usability and robustness of MPIC have been appreciated by many IronCAD users. Each year, additional improvements and refinement have been added to further increase the ease of use as well as the functionalities that sets it apart from the competition. Most of these new features are based on user feedback and requests to speed up the design cycle, simplify analysis setup, and reduce analysis times.

MPIC 2020, includes several new and improved key technologies designed specifically for CAD design analysis. IronCAD’s focus was on general CAD designers and users who want to adopt design analysis earlier in the digital prototyping cycle and aim to provide accurate, realistic and quick analysis. As such, most of these improvements are in the assembly analysis functionalities.

Some of MPIC 2020 new technologies and features include:

• New tolerance assembly analysis technology is implemented with respect to how parts are assembled and meshed for analysis. This new option uses parts’ discrete boundary surface facets to smartly unite parts together for design analysis. This technology enables the healing of CAD assembly models with intentional or unintentional gaps so they can be glued together for quick design analysis.

• New drag-and-drop user interface has been implemented in the part tree of materials, boundary condition constraints, and load areas. Users can select the part’s tree node and drag it to a different material tree to quickly assign it to a different material. In boundary condition constraints and loading, the sequence of the priority of the constraint can also be changed by selecting the condition and drag it up/down to change the priority of the boundary condition.

• MPIC model is now upgraded to XMD 2.2 model and compatible with all AMPS product lines. It can be opened, modified, and analyzed by any AMPS XMD application if additional features/capabilities are needed.

Multiphysics for IronCAD offers basic to advance versions that include non-linear, fluid, dynamics, and rigid body kinematics. Once installed, users have access to the full functionality limited to 2000 mesh nodes that can be used to get started with the analysis application. You can access the latest Multiphysics for IronCAD 2020.

“This new release with new tolerance assembly analysis technology will streamline the design analysis for design engineering beyond anything in the market today” stated Cary O’Connor, V.P. of Marketing of IronCAD. “Users will be able to quickly design products and assemblies with accurate design simulation easily without having to struggle with gaps and inaccuracies often found in CAD designs that don’t fully model manufacturing processes such as welds and fixturing. Overall, users can improve designs and design-to-product times with this new functionality” he continued.

Dr. Ted Lin of AMPS Technologies, developers of MPIC, and meshing technology partner Dr. Mark Beall, President of Simmetrix Inc. says, “For more than three years of development and testing, our team has taken on this task to resolve this well-known problem in CAD models. This new technology gives the user more control over gluing together parts in assembly models with intentional or unintentional gaps for quick design analysis that virtually eliminates the CAD modeling inaccuracy issues that users struggled to resolve in the past.”

IronCAD
www.ironcad.com

Leading 3D Printing Company Appoints New CEO

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Stratasys Ltd., a maker of additive manufacturing and 3D printing technology, has appointed a new chief executive officer.

Yoav Zeif will take the helm in middle February, with current Interim Chief Executive Officer Elchanan Jaglom continuing as chairman.

Based in Eden Prairie, Minnesota, Stratasys, Inc. manufactures rapid prototyping machines that produce physical models from computer designs using fused deposition modeling technology.

At Netafim, a micro-irrigation company, Zeif was president of the americas division and head of product offering and chief commercial officer. He was also senior vice president of products and marketing at Makhteshim (now Adama Ltd.), a global crop-protection company. Since 2018, he’s been a partner in the New York office of McKinsey & Company.

“Stratasys has led the expansion of the 3-D printing industry for more than three decades, but the potential impact of this transformative technology across all industries is just beginning,” Jaglom says. “Yoav brings the strong combination of leadership and global operational experience to fuel our next stage of growth. We are confident that as CEO he will advance our offering and further our vision to reshape the world of design, prototyping and manufacturing.”

Last year, Stratasys introduced its F120 printer, an industrial-grade 3D printer.

Although engineers and designers have benefited greatly from the introduction of computer-aided design, they still need a physical copy in order to check the viability of their ideas, Jaglom says. Designers would spend time making models by hand. With the introduction of rapid prototyping machines, such as those made by Stratasys, CAD designs could be turned into a prototype in a matter of hours, available in a variety of materials.

Fused deposition modeling (FDM) technology relies on a high-speed robotic arm and an extruding head, in effect a glue gun, to spray melted thermoplastic filament. Relying on CAD coding, the gun moves over a platform, plotting small dots of plastic to create a model from the bottom up in a thermally controlled modeling chamber.

Although Stratasys continues to make high-end products, the company has enjoyed success with 3-D printers that cost less than $25,000, making the technology available to a much wider range of customers, including schools. Because the machines require no special venting or chemical post-processing they are also suitable for office use, Jaglom says.

With Zeif’s responsibility spanning dozens of global geographies and multiple lines of business, Zeif delivered growth rates significantly higher than the surrounding market, Jaglom says.

Stratasys pioneered and continues to power the additive manufacturing landscape, enabling companies across virtually all industries to build and improve their businesses through 3D printing technology,” Zeif says. “In particular, thanks to its outstanding innovations and application engineering, it is clear that Stratasys is poised not only to reshape product development and prototyping but also to transform supply chains and manufacturing through efficiency and personalization.”

Stratasys was founded by the husband and wife team of Scott Crump and Lisa Crump. In 1988, Crump decided to make a toy frog for his young daughter using a glue gun loaded with a mixture of polyethylene and candle wax. His idea was to create the shape layer by layer. He then thought of a way to automate the process, spent $10,000 on digital-plotting equipment, and devoted weekend hours to the project.

The couple founded the company in 1988 and in 1989 he patented FDM technology.