Mitigating Risk of UAV Collisions Using Explicit Dynamics

drone UAV explicit dynamicsUnmanned aerial vehicles, in short UAVs or drones, have become very popular both in the industrial and consumer space. With the number of units expected to reach 67 million by 2021 the potential for accidents and collisions with manned air vehicles is real. Understanding and mitigating the impact of UAV collisions using pervasive engineering simulation and explicit dynamics will be the key to helping accelerate the acceptance of drones into commercial airspace without sacrificing safety. Continue reading

Additive Manufacturing, Topology Optimization and 3-D Printing

Additive manufacturing (AM), topology optimization and 3-D printing have produced some remarkable changes in the manufacturing sector, enabling companies to make parts whose geometries would have been all but impossible using traditional techniques. Still, being a relatively young technology, AM faces some challenges before it can enjoy more widespread use.

One of our largest customers has categorized these challenges, in order of importance to them:

  1. Build volume (the size of the part that they are able to make): While tiny and complex is interesting, large and complex is where the money is.
  2. Build speed: Even with a new facility with 100 DMLS (Direct Metal Laser Sintering) machines to print one part, 24 hours a day, every day, this customer can’t manufacture parts fast enough to keep up with demand.
  3. Build failures: These are caused by thermal distortions, build plate connection failures, interference with the powder spreading mechanism because of distortion, etc.

We’ll discuss the obstacles and potential solutions for the first two of these items today. In a future blog, we’ll take up the issue of build failures and one other industry-wide concern:

  1. Confidence in the material properties being produced: How can we be sure that a part made using AM has consistent mechanical properties throughout the part?

Let’s take a closer look at the first two issues.

Additive Manufacturing and Build volume

Parts made by AM tend to be tiny. These parts have incredible resolution, with details that could not be made by any other process — not casting, and not subtractive machining. Metal AM started out as a bit of a novelty item, great for printing desktop trophies to show things like metal lattice structures balanced on the head of a dandelion gone to seed, but not really very good at printing parts that actually did anything useful. Where was the problem, why were the build volumes small?  The difficulty was in scaling up the internal mechanisms for the DMLS machines — the powder spreaders and the laser controls.  Making these mechanisms larger while maintaining the incredible resolution required to produce precision parts proved to be problematic.

topology optimization

Highly-detailed Additive Manufacturing part

But that’s changing, and relatively quickly. Smart engineers are producing ever larger control and material handling systems, while maintaining the precision for which the AM processes are known. ExOne, for instance, is producing machines that print not the part, but the mold for traditional casting, and these molds are nearly the size of a pickup truck bed. Also, DMLS machines, the predominant commercial choice of aerospace companies, are getting larger and larger, so much so that it’s possible to print multiple versions of the same part at the same time, with no loss of the precision that would sacrifice surface finish, material properties, etc. It’s obvious that engineers are quickly solving the scale-up challenge.

Additive Manufacturing and Build speed

While the precision parts, particularly in metal, that are coming out of today’s AM machines are marvels to hold, spin, bolt to your car, etc., it can be maddening to watch an AM machine at work. Many builds take up to 8 hours. Two of the biggest factors in build speed are layer thickness and laser travel velocity. Smart companies have already started tackling this problem from a number of different angles. Several companies have put multiple lasers in the same machine, with multiple control mechanisms. Productivity scales nicely when you do that. So, if one laser is good, and two lasers is better, then what about three?

This reminds me of the razor blade wars that went on for a while. For many years, there was one razor, then there were two and it was a huge breakthrough in shaving speed and reduced bloodletting potential. Then there were three blades, then four. I have no idea how many blades are in vogue now, whether they are stationary, or vibrate or what, but it’s billions of dollars in market value for something that seems pretty simple, in hindsight.  (Why didn’t I think of that?)  But, back to the point, Additive manufacturing production speeds are going up rapidly, and, no coincidence, so are the number of AM parts being put into service as final production parts.

So, additive manufacturing may have some problems, but problems with great promise attract great minds, and these minds are knocking down the barriers faster than most thought possible. Some forward thinking companies are racing into the age of additive manufacturing, while others are cautiously optimistic and taking a wait and see approach.

Additive manufacturing at the University of Pittsburgh

Clearly, there is much that remains to be done in the future. ANSYS took a step toward that future by partnering with the University of Pittsburgh to establish the ANSYS Additive Manufacturing Research Laboratory at the Swanson School of Engineering in June 2016. Researchers collaborating with ANSYS engineers in the laboratory will put the power of ANSYS simulation solutions to overcome some of these challenges.
optimized topology

Optimized topology using ANSYS Mechanical

Also, the recently released ANSYS 18 contains a new topology optimization feature in ANSYS Mechanical can define the region and loads for a given scenario or multiple scenarios, and let the solver use a physics-driven approach.

Attend the webinar on February 14th to learn about all the enhancements to ANSYS Mechanical, for additive manufacturing and for other engineering applications. And watch for our second blog in this series, in which we’ll tackle challenges 3 and 4 listed above.

ANSYS 18 Delivers Pervasive Engineering Simulation

ANSYS 18 pervasive engineering simulationIt’s no exaggeration to say that simulation is more important than ever in today’s rapidly expanding industrial and consumer environment. Our customers are pushing the boundaries of engineering simulation in ways we could never have imagined. Tomorrow’s release of the latest version of our suite of simulation solutions, ANSYS 18, will help them to keep pushing these boundaries. Continue reading

3-D Design Helps Pool Cleaning, Accessibility Go Swimmingly

What comes to mind when you think of public swimming pools?  A refreshing escape from the summer heat? Children playing and swimming? Free-swimmers, divers, and water polo players jockeying for limited space? How 3-D design makes pools cleaner and more accessible for everyone? Hmm. I may need to explain that last one.

While many of us focus on the positive aspects, there are some of us who avoid public pools: non-swimmers, of course; people concerned about bacteria and other health issues; and people with reduced mobility (PMR) who find accessing public pools difficult to manage and unwelcoming.

Hexagone, a French company founded in 1987, has made its mission to serve these last two categories of recreationists, designing and equipping public pools with professional high-tech cleaning devices and creating solutions that increase PMR accessibility and safety. Continue reading

Dragonfly: The Mysterious Insect Driving Engineering Innovation

Who hasn’t dreamt of flying like a bird? From Leonardo da Vinci’s drawings of flying machines to Otto Lilienthal’s gliders, inventors have focused, quite logically, on human transport. We now take flying on airplanes for granted. But mechanical flight on a smaller, insect-level scale is less well-known. Micro-air vehicles (MAVs) have gained popularity in recent years due to wide range of small-scale applications in areas such as military, transportation, electronics, security systems, search and rescue missions, video recordings and many more. Successful prototypes depend upon valid, yet imaginative, designs as a starting point.  Continue reading

Multiphysics Simulation of a Car Side Mirror with ANSYS AIM

One of the most important problems in the automotive industry is the general multiphysics simulation of coupled phenomena, where multiple — and sometimes conflicting — conditions need to be accounted for, all at the same time. One common application is the resistive heating of a car side mirror.

Designing the mechanism for keeping the mirror defrosted must also take into account the structural response of the mirror as the external environmental conditions, such as air pressure and cold temperature, cause physical stress and thermal deformation. The task is a base requirement of the automotive industry and requires a full multiphysics approach, which is still a challenge for common finite element method (FEM) simulation. In this post, we’ll show you how our engineers at SVS FEM used ANSYS AIM to model a side mirror and multiphysics analysis to solve some of its difficult design problems. Continue reading

Design Subsea ROV Faster and Better with ANSYS CFD

The ROV, or subsea remotely-operated vehicle, is frequently used in marine operations such as underwater mapping, pipeline inspection and surveillance, sending payload, maintenance and operations on subsea oil and gas equipment such as BOP (blowout preventer) and Christmas tree assembly, which controls the oil/gas/water flow out of the well.

Underwater environments create various challenges for the manufacturers of the vehicle robotics. In addition to structure integrity under high pressure, complex underwater hydrodynamics characteristics due to coupling of motions in 6 degrees of freedom needs to be considered. Continue reading

Smart Home Technology and Simulation Solutions

smart home technologyThe concept of the “automated home and smart home” was first introduced over 80 years ago, and has been facing different technical limitations since then.

Recently, service providers and home appliance manufacturers have launched a new initiative to bring the concept of smart homes to reality allowing subscribers to remotely manage and monitor different home devices from anywhere via smart phones or over the web with no physical distance limitations. Continue reading

Defining the Future of Cloud-based Engineering Simulation: ANSYS at AWS re:Invent 2016

Each year the cloud faithful converge on Las Vegas in the fall for AWS re:Invent. This year’s event delivered exciting announcements for ANSYS users interested in performing engineering simulation on the AWS cloud.

With well over 30,000 attendees, the 2016 conference was too big to be contained within the expansive Venetian hotel/Sands expo complex and it spilled across into adjacent facilities (comfortable shoes were a requirement). Wednesday’s keynote session by Andy Jassy, CEO and Thursday’s session by Werner Vogels, CTO highlighted the growing reach of AWS. The conference featured a staggering number of new features, services and some powerful new hardware. Continue reading

Submodeling: Simple Solutions for Large-Scale Problems

If you’re an engineer who has dealt with large simulation models, you know there’s often a trade-off between accuracy and solution time. Submodeling is a technique you can use to reduce solution time without sacrificing accuracy of results.

A common strategy you can use to look at the overall behavior of an assembly or complex part of a large model is to simplify the model during preparation by removing small details, like fillets and holes. Simplifying models in this way can have a significant impact on run times. This simplification, while not excessively affecting overall model stiffness, may result in lower resolution of localized stresses. What you need, then, is a mechanism that allows you to “zoom in” on these details to examine behavior around specific areas.

Continue reading