Home to a major aerospace cluster in Mexico, it follows successful models such as Toulouse, Wichita, Montreal, and Seattle.
Home to a major aerospace cluster in Mexico, it follows successful models such as Toulouse, Wichita, Montreal, and Seattle.
The term does not matter – additive manufacturing (AM) and 3D printing (3D) are interchangeable. Understanding the market, where it’s going, how it’s used, what it means to manufacturers, and who to turn to for more knowledge and support does matter.
AM/3D printing is growing. According to the 19th edition of the Wohlers Report, published by Wohlers Associates Inc., companies are pushing the limits of AM/3D printing and applying the technology in new ways. The research projects the AM/3D printing industry to reach $12.8 billion by 2018, estimating it grew $3.07 billion in 2013. By 2020, forecasted revenue should exceed $21 billion.
“The industry is experiencing change that has not been seen in 20-plus years,” states Tim Caffrey, senior consultant at Wohlers Associates, and one of two principal authors on the report. “What’s most exciting is that we have barely scratched the surface of what’s possible.”
Terry Wohlers, president and the other principal author, says revenues from the production of parts for final products represents 34.7% of the entire market for AM and 3D printing. In 2013, the AM market segment of parts for final products topped the $1 billion mark, and aerospace, medical, dental, and other industries “are finding ways to use AM to produce quality parts.”
Metal parts production is increasing in popularity as the number of AM/3D machines that produce metal parts has skyrocketed, jumping to 348 units in 2013 from 198 a year earlier, a 75.8% increase. Companies such as Airbus and General Electric are using this technology to produce complex metal parts, says Wohlers, who has followed the market for metal AM machines for 14 years.
But, what if you are new to the market, where do you turn to learn more?
Throughout this special report, materials, machines, processes, and the players offer new and experienced AM/3D users a look at what’s to come.
A terminology primer
The term additive manufacturing (AM) represents many technological subsets also known as:
AM builds 3D objects, layer-by-layer, using a range of materials. Designs are created in CAD using a 3D modeling program or via a 3D scanner that makes a digital copy of an existing object, which is then uploaded into the CAD 3D modeling program.
Then, the software slices the final CAD model into hundreds to thousands of horizontal layers so when the file is uploaded to the AM machine, the design can be read, layer-by-layer as a 2D image, which once built, results in the three-dimensional finished product.
The processes used to create 3D products also varies. The most common are:
According to Sharon L.N. Ford, author of the most recent report from the U.S. International Trade Commission (USITC), “Additive Manufacturing Technology: Potential Implications for U.S. Manufacturing Competitiveness,” AM/3D printing offers industry a range of unique possibilities. The technology can produce three-dimensional objects of virtually any geometry without significantly increasing costs. It also has the potential to reduce – or even eliminate – the constraints of molds and dies. Due to AM/3D printing’s speed and efficiency in producing prototypes and parts, the technology will have the greatest impact on products requiring customization, having complex designs, and being made in small quantities.
Most frequently associated with medical and aerospace applications, the largest consumer of AM/3D technology, as of 2011, was the automotive industry – making up 19.5% of all purchases, according to the USITC report. Medical use followed at 15.1% and aerospace makes up 12.1% of the market.
AM/3D printing techniques make up barely 0.01% of all automotive manufacturing, but are more common in medical (0.04% of total industry output) and aerospace (0.02% of industry output).
Ford notes that AM/3D printing is not yet suitable for mass production due to limitations such as lengthy build time, limited object sizes, machine costs, and sizes, and materials used. For example, while the process is capable of creating a 1.5" cube per hour, on average, an injection-molding machine can produce several similar parts in less than a minute.
However, technology is changing – rapidly – and the functionality is gaining support from innovation hubs to even machine tool builders.
AM extends part life, reduces costs
Challenge: Extending the life of rotor and stators for Ulterra’s downhole drilling applications
Costs by method
ExOne’s M-Flex prints in stainless steel, bronze, or tungsten. Its flexible job box can print one prototype or short runs of multiple and/or custom parts.
Youngstown, Ohio-based America Makes is an extensive network of more than 100 companies, non-profit organizations, academic institutions, and government agencies from across the United States.
Founded in August 2012 as the flagship institute in the National Network for Manufacturing Innovation (NNMI), it leverages technical minds from government, industry, and academia to accelerate the adoption of AM/3D printing technologies in the U.S. manufacturing sector.
According to Rob Gorham, director of operations, the goal is to create manufacturing competitiveness through a truly collaborative environment, bringing technical advancements from the lab to the factory floor, creating jobs, and producing products that are more competitive on a global scale.
However, not all industries have adopted AM/3D printing in their operations, and some are not sure where to start. Clearing the haze is one area of assistance the institute offers.
Gorham says his group is working in early stage problems such as standards, design methodologies, tools, materials, process control, equipment, non-destructive evaluation, qualification, certification, and supply chain integration.
Another initiative of the institute is validating materials and techniques. “America Makes is leading an effort to qualify materials and the mid-tier supply chain partner to the multiple aerospace OEM specifications.”
Another project addresses the metal casting industry and its need to understand the opportunity AM/3D printing brings to the bottom line. A result of the metal-casting project is a collaboration among several top-tier metal castings suppliers to build demonstrations, use cases, and validate the benefits of AM/3D printing in their industries.
“It’s a truly collaborative environment that brings technical advancements from the lab to the factory floor, creates jobs, produces more competitive products, and ultimately reaffirms our place in the global market,” Gorham states.
As additive manufacturing continues to advance, materials and product qualification testing becomes crucial.
By David Podrug
The opportunities for innovation are endless, given the increasingly diverse challenges that organizations attempt to address through AM. In the aerospace sector, primes and their suppliers are constantly seeking to reduce the weight of aircraft to deliver improved efficiencies in fuelling. Energy companies are looking to increase mass customization and energy efficiency. Industries with high-volume manufacture, such as transportation and medical devices, are demanding significant cost reductions through shorter development times and new component production methods.
However, the reality of industry-wide adoption is less plausible if the risks of producing parts and components by AM are not fully understood. At Element Materials Technology, engineers are developing international testing methods and standards needed to adopt AM. Industry collaboration on certification and qualification of materials and components is crucial.
Pushing AM to its limits
Traditional subtractive manufacturing processes – such as pouring steel into ingots – deliver predictable properties. Changes to the manufacturing process can bring complexities not encountered previously. For example, in AM, issues may develop that cause unpredictability between layers.
The complex range of existing standards require deep knowledge of testing to ensure that innovation in AM is not stalled by failure to anticipate properties and performance. Element has the capabilities to qualify and inspect materials across a range of industries. For example, within the aerospace sector, engineers conduct non-destructive testing (NDT) for applications in space hardware; mechanical, physical, and chemical testing on metallic materials for space applications; fatigue testing of metals for jet engines; and allowables testing on non-metallic materials for commercial and military aircraft. NDT enables clients to make the most of new processes without compromising on their commitments to quality and safety.
Collaboration and qualification
Element offers expert opinion on testing methodologies used by manufacturers and engineers, enabling them to improve their internal processes beyond their existing capabilities.
The future of AM
One initiative to ensure this is Committee F42, an international body led by ASTM and ISO to create and publish the test methods needed to validate additively manufactured components and parts. Element is represented on the committee and is driving the development of international testing standards from its AM Center of Technical Excellence in Cleveland, Ohio. Overcoming the challenges that AM poses will allow us to determine the level of testing required to ensure consistent production, the properties at risk, and detection of critical flaw sizes more accurately than before.
Element Materials Technology
When considering a new process, designers must determine which parts are candidates. AM/3D printing is generally better for complex parts with difficult-to-machine geometries, but the tradeoff is reduced speed compared to CNC machining. The choices have grown now that machine tool builders are offering hybrid technologies for start-to-finish processes.
Greg Langenhorst, technical marketing manager, MC Machinery Systems, offers one example of where AM fits nicely – mold-and-die production where effectively cooling parts is vital so they do not warp and can be ejected quickly.
“A big advantage of AM powder-metal sintering is the ability to build conforming cooling channels within a mold. Precisely located channels made this way allow 20% to 30% faster part cooling and better part accuracy with less warping and shrinkage,” Langenhorst states. “The problem is that laser-sintering alone cannot produce finished surfaces in these channels – that requires a separate milling step. But, AM produces complex geometries that do not always allow machining after the build. The solution is to incorporate milling while the AM part is created, layer by layer.”
One machine, the LUMEX Avance-25, combines laser sintering and CNC-milling in one platform. The 400W fiber-laser sinters at 5,000mm/sec, adding layers 50µm (0.002") thick. Once 10 layers are put down, a mill as small as 0.6mm (0.024") in diameter can finish the surface, eliminating ridge lines. Rib shapes as small as 0.02" can be finished in a core as it is being built. Applications have included molds for plastic electric drill casings and automotive connector plugs.
“Because you no longer have to design to your manufacturing capability, you can design for the optimization of whatever the part needs to be,” Lagenhorst says. “You can put cooling channels where you want, without worrying about twists and turns.”
Another hybrid machine is DMG MORI’s Lasertec 65 3D, a laser deposition welding and milling machine. Combining additive manufacturing and traditional cutting methods enables new applications and geometries. The changeover from laser allows direct milling of sections not reachable at the finished part. DMG MORI engineers designed the machine to completely melt the powder metal alloy as it is sprayed into the focal point of the laser. The laser melts both the powder and the substrate, producing full bonding between the two mediums.
Renishaw, a global engineering technologies company focused on machining, metrology, and process control is also actively participating in the AM/3D printing field. Offering a laser melting process, Renishaw’s AM250 additive manufacturing machine benefits injection mold producers. Using a high-powered fiber laser, Renishaw’s system melts and fuses metal powder grains (steel, aluminum, and other materials). The machine can build up complex parts, layer-upon-layer of fused metal. Layer thicknesses range from 20µm to 100µm. Low-volume parts for medical companies, aerospace contractors, or motorsports competitors can go directly from the laser machine to the user.
GKN Aerospace’s additive focus
The company’s AM program extends across the value chain, taking in new materials, applications, processes, and part qualification.
By Rob Sharman
GKN Aerospace is researching and developing programs to advance a variety of additive manufacturing (AM) techniques. Because AM creates the material as it makes parts, these processes open up new possibilities for component and system design. Eventually, we will develop totally new materials and functionally graded structures.
To obtain aerospace qualification for AM-produced components, GKN Aerospace is investing heavily in testing – and standardizing – processes and materials to generate quality procedures. AM-manufactured parts are flying today, and the company expects the number of additive parts to increase significantly during the next 2 to 5 years.
In parallel, the company is developing a thorough understanding of the design freedom afforded by AM, the processes and materials involved, and what will be required to produce the entirely novel parts needed for the next generation of aircraft.
Activity focuses on several AM technologies, including:
AM processes promise to revolutionize aerospace component manufacturing by enabling the creation of new, efficient, lightweight designs, made by tailored, higher performing materials. Simultaneously, these developments will lower material waste associated with subtractive processes, reduce time and energy required in manufacture, and lower carbon emissions. AM will allow material optimization throughout the component and, most significantly, flip the established cost/complexity equation familiar to manufacturing, enabling design optimization and a level of structural complexity that is not cost effective – or simply not achievable – to manufacture today.
About the author: Rob Sharman is head of Additive Manufacture, GKN Aerospace, and can be reached at email@example.com.
Beyond the machines are the materials used. Poly-ether-ketone-ketone (PEKK) is used widely in injection-molded parts, but Oxford Performance Materials (OPM) of South Windsor, Connecticut, wanted to use the high-performance plastic in laser sintering to replace aluminum and magnesium in parts.
OPM has three divisions: biomedical raw materials that uses PEKK-polymer-based OXPEKK material; a biomedical devices section that produces molded and selective-laser-sintered (SLS) OsteoFab medical parts and implants from OXPEKK polymers; and an industrial parts group that focuses on aerospace parts production.
OPM is a full-service provider, not a service bureau, notes Larry Varholak, vice president of programs, OPM Aerospace & Industrial. A proprietary design algorithm determines a proposed part’s structural form to maximize strength, flexibility, and weight. The design is then 3D-printed directly from the digital file using SLS. The company can create complex parts otherwise too expensive to produce conventionally, in a build volume up to 16" x 20" x 22", using an EOS P800 machine.
If PEKK is to replace metals, it is essential to qualify its performance characteristics. One of OPM’s first goals was to set up design allowables for PEKK to take advantage of additive manufacturing, according to Paul Martin, president of OPM Aerospace & Industrial.
“OPM has developed a database of strength characteristics of the material to know its limits from more than 3,400 test components,” Martin states. “We view ourselves as halfway between metal and nylon. Compared to aluminum fabrication, we can produce complex and expensive parts at a fraction of the cost.”
Cutting through AM clutter
Searching for the right additive manufacturing (AM) machines, material, or both used to be a monumental task, but the Senvol Database changes all that.
Senvol, a consulting firm offering quantitatively focused AM analytics, built a database of available machines and materials clients could use to cross-reference machines and materials that went together.
Launched in January 2015, the free, online Senvol Database currently contains detailed specs on more than 350 industrial AM machines and 450 materials.
When searching for machines, users choose from drop-down menus for manufacturers, model, process, and materials, and then have the option to input the minimum size of the build envelope required. Results display all available machines that fit the criteria. Users can then click on the details button for additional machine information. Searching for material offers input criteria for hardness, physical, thermal, and mechanical properties.
Results are not linked to the actual company, but the Senvol Database winnows the results to a manageable list for further research. Once the user has the cross-reference results, visiting that manufacturer’s website will garner the specifics to start the in-depth comparison process.
CNC to FDM
Advanced Composite Structures (ACS) repairs helicopter rotor blades and other composite structures for fixed-wing and rotary-wing aircraft, and produces low-volume production composite parts for the aerospace industry. Both offerings require tooling while many jobs also require fixtures to locate secondary operations, such as drilling.
Producing a model and molding a composite layup tool cost about the same. In both cases, lead times were 8 to 10 weeks.
For example, ACS recently produced a camera fairing for a forward-looking infrared camera on a military aircraft. The Fortus machine built the layup tool directly from a CAD drawing. In another example, the geometry of a vertical fin assembly for a helicopter is so simple that a layup mandrel was not needed. However, the Fortus machine produced a drill fixture to accurately locate a series of holes.
“Tools produced with FDM cost only about 20% as much as CNC-produced tooling,” says Bruce Anning, owner of ACS. “Moving from traditional methods to producing composite tooling with FDM has helped us substantially improve our competitive position.”
Advanced Composite Structures
There is so much more to tell, but one thing comes through: this disruptive technology is entering mainstream acceptance, with many players joining the market. From machines to materials to processes, AM/3D printing has changed the way certain parts are manufactured, and it is opening new areas of part production.
MC Machinery Systems Inc.
Oxford Performance Materials
About the author: Elizabeth Engler Modic is the editor of Aerospace Manufacturing and Design and can be reached at firstname.lastname@example.org or 216.393.0264.
The latest carbon-fiber composite materials used in Boeing’s 787 Dreamliner and Airbus’s A350 are up to 20% lighter than conventional aluminum, leading to better fuel efficiency and longer flights. To take full advantage of these materials, aircraft manufacturers and maintenance repair organizations (MROs) still have to contain their airborne dust, foreign object debris (FOD), and particulates when grinding, sanding, and cutting.
To optimize operations, aerospace manufacturers and MROs are increasingly adopting the best practice of clean as you go. From composites to hexavalent chromium to cadmium, vacuum capture of dangerous dust, FOD, and particulates at the source is enhancing aircraft safety, quality, and production.
GE Aviation’s Batesville, Mississippi, composites plant sought to proactively identify and reduce dust since cleanliness is vital to quality manufacturing.
“We’ve had everyone from 60 Minutes to Federal Aviation Administration (FAA) quality inspectors tour our site, and our product requires us to have clean rooms,” says Curt Curtis, technical leader of the Batesville plant’s manufacturing shop.
GE Aviation’s Batesville plant produces two composite parts for GE’s GEnx jet engine: fan platforms (installed between the engine’s front fan blades) and the fan case assembly (a large circular structure that encases the front fan). The GEnx engine powers Boeing 787 and 747-8 aircraft and is the first with composite fan blades, fan platforms, and fan case assemblies.
Compared with traditional aluminum airframe components, composite components provide engine weight savings and greater durability, resulting in better aircraft fuel efficiency as well as reduced maintenance and replacement costs. Compared with a typical aluminum fan case with titanium blades, Curtis says the composite GEnx engine fan case and fan blades save more than 300 lb per engine.
According to Curtis, the composite process has a significant amount of handwork involved to finish the product properly. After curing the material, certain areas require blending, smoothing, and removal of excess material, called flash, typically using handtools such as sanders and grinders.
“Our rule is to capture dust at the point it’s created because cleanliness is our first line of defense against any potential quality issues,” Curtis says.
According to Curtis, the Batesville plant brings smaller composite parts inside a dust containment booth to finish them. “But larger composite components like our fan cases, which are about 10ft in diameter, weren’t practical to bring inside a containment booth,” Curtis says. “That’s when using a tool shroud is critical since that essentially becomes the dust containment booth.”
After the Batesville plant conducted an aerospace industry literature study and evaluation, it chose DCM Clean-Air Products equipment. The Fort Worth, Texas-based manufacturer of power hand tools designed for source capture of airborne particulates, offers a line of HEPA vacuums, sanders, grinders, drills, routers, buffers, and shrouds for custom applications.
Curtis says, “To enhance quality and safety, we required strong, reliable vacuum suction with HEPA filters and tool shrouds to capture any composite dust at the source.”
In aircraft MRO, sanding, grinding, sawing, or drilling can launch a plume of dust, FOD, and small particulate across the aircraft and worksite. Often this can endanger worker safety while hindering quality and production if work must be stopped to thoroughly clean the product and worksite.
“When doing a composite repair, cutting out an area, and grinding it down, you’re putting particulates and volatiles in the air,” explains Scott Malcomb, a JetBlue University instructor at Orlando International Airport, who teaches advanced composites to a select group of technicians. “While those doing the repair usually wear respirators, gloves, goggles, and sleeves, people around them typically aren’t wearing protective equipment, so they’re getting exposed.”
The Occupational Safety and Health Administration (OSHA) has not required personal protective equipment (PPE) for exposure to most composite reinforcement fibers since they do not pose a health risk in dry fabric form or when cured in a resin matrix, but machining a cured laminate can get short fibers airborne. This is a potential concern if the short fibers are inhaled and damage lung tissue.
“While airborne composite materials aren’t officially considered a respiratory hazard, safety managers would be wise to remember that asbestos was once considered safe,” Malcomb says. “Best practice technique is to vacuum-extract composite dust and debris at the source so it doesn’t get airborne, scatter as FOD, or have to be cleaned up later.”
Besides composites, other dusts and debris can be even more important to control. According to an OSHA report, hexavalent chromium [Cr(VI)], a toxic form of chromium, is often used in the form of zinc chromate as an aerospace paint primer, varnish, and pigment. It is toxic when inhaled as an airborne dust, fume, or mist, and can cause lung cancer.
The OSHA report states, “Surfaces contaminated with Cr(VI) must be cleaned by HEPA-filtered vacuuming or other methods to minimize exposure to Cr(VI).”
Cadmium dust and FOD from frozen fasteners, drilled out during maintenance, can be toxic and dangerous as well. The airborne dust of many materials such as aluminum can ignite or explode if set off by a spark, blowtorch, or other ignition source.
FOD damage is estimated to cost the aerospace industry $4 billion a year. Not only can FOD cause product rejection by aircraft OEMs and suppliers, it can also lead to catastrophic failure if it interferes with mission-critical equipment.
To control dust and debris in materials such as aluminum, the aerospace industry has long used vacuum extraction. Now, vacuum capture of dangerous dust, FOD, and particulates at the source is being extended as a best practice in materials such as composites and hexavalent chromium to enhance safety, quality, and production.
“Since the product is only as strong as its weakest link, today vacuum capture increasingly follows a whole system approach, usually involving everything from the abrasive to the tools, hoses, and vacuums, ensuring that harmful dust and debris is safely handled at each step of the process,” says Brad Clayton, vice president of Clayton Associates, a Lakewood, New Jersey-based supplier of source capture tools and vacuum sanding equipment.
Associated Painters, a service provider for aircraft manufacturers, modification centers, and airlines uses a complete vacuum extraction system to control dust and particulate matter when mechanically removing old paint with sanders before repainting.
“Capturing dust and particulate at the source protects everyone across the entire worksite, improves the quality of the paint job, and helps us comply with FAA, EPA, and OSHA regulations,” says Mike Wilkins, purchasing manager for both Associated Painters and Leading Edge Aviation Services, another aerospace service provider.
Wilkins finds that preventing dust and particulates from circulating around the worksite is much more effective than traditionally hosing down the floor and using squeegees to scrape waste material into trenches to pick up later.
“Our operators are safer, more comfortable, and about 8% to 10% more productive using Clayton sanders with tool shrouds and DustMaster vacuums with custom hoses,” says Wilkins, whose operators still wear protective suits and respiratory masks as a work precaution. “Our paint jobs are better since there’s no dust or particulate getting kicked up to settle on the paint. There is no dust or particulate to clean up after we use the vacuums.”
Malcomb’s JetBlue University advanced composites class also uses a complete vacuum extraction system to control particulates when grinding and removing a damaged section of carbon fiber or fiberglass material.
“In an enclosed area like our class or a shop, controlling particulate at the source is even more important,” Malcomb says. “We run four people at a time on a repair, three on our Clayton DustMaster unit, and another on a single unit.”
According to Malcomb, the larger unit is a complete, lockable, HEPA filter vacuum system configured for aerospace maintenance, with three hoses for simultaneous use. A safe filter-change process allows workers to change filters without re-introducing dust and pollutants into the air.
Since both the larger and smaller units are portable, advanced composites class students will use them for repairs in the field as well.
“Our students will not only use the vacuum extraction units in the training room but also will roll them out to do on-wing repairs on the hangar floor,” Malcomb says.
According to Malcomb, after his select group of about 20 to 25 advanced composite class students are fully trained, they will be stationed in New York City, Boston, and Orlando to do necessary JetBlue light check composite repairs.
“Safety, environmental, and production managers need to look into source capture vacuum equipment,” Malcomb concludes. “As aircraft MROs begin to use these systems, they will move from best practice to standard procedure because of the way they help to optimize safety, quality, and production.”
Clayton Associates Inc.
DCM Clean Air Products
What if you could have a robot assist a repetitive manual-labor task such as deburring holes on turbine blades? Steven Somes, president of Cleveland-based startup company Force Robots, asked himself that question, and it led him to develop a unique solution that reduces cycle times and results in more consistent results.
Somes, a controls engineer, was doing automation for a large industrial company when he attended grad school at Case Western Reserve University. There, he became interested in robotics and force control. His goal was to determine what was needed to make an industrial-class robot that could magnify torque while having direct-drive performance – in other words, perfectly smooth operation. To reduce inertia, he’d have to make it as light weight as possible, while still retaining high torsional stiffness.
“And it had to generate only as much force as you’d expect from a person,” Somes adds.
Somes’ quest took 12 years to get from the idea to the prototype machine. He says National Science Foundation grants helped the process, as did funding from the Ohio Third Frontier, an internationally recognized technology-based economic development initiative.
The fruit of Somes’ and his small team’s labors is the Touch Robot, a system that performs precision grinding and machining to polish, deburr, and deflash cast and forged parts. This process has proven extremely difficult to automate, plus metal finishing with hand tools is a difficult task that can risk repetitive stress injury.
Force Robots’ system “combines the precision of a machine with the finesse of the human hand,” Somes says.
It is designed to feel existing part contours, match those to a CAD reference, and work autonomously to remove material to specification.
The Touch Robot is self-contained, portable, and can be carried through a standard-size door. It requires only 120VAC and shop air to operate. A 4-axis material-removal arm and a 2-axis part-positioner are mounted to the 1.2m x 0.8m work table. Dividing the system’s six degrees of freedom between the two coordinated mechanisms is the heart of the device – it preserves a soft touch of the tool arm while allowing heavy castings up to 0.4m long to be manipulated. No force or optical sensing is required for it to work; its feedback is derived from the motor encoders.
Its brushless, slot-less, 24VDC drive motors keep joint speeds below a level where the arm could endanger an operator. This modest force capacity and low-friction, back-drivable joints make it easily overpowered by a human. Joint limits restrict its reach to 0.5m, allowing it to be safely deployed alongside manual metal finishing cells.
Somes compares the system to a labor-saving appliance. “Operators can task it with the heaviest, most difficult material removal work, while they focus on fine finishing and inspection. The key to performance is low friction, perfectly smooth action, just like a human arm,” Somes explains.
To achieve this smooth operation, the Touch Robot uses stainless steel, aircraft-grade cables, pre-stressed and nylon-coated, that wind around a capstan with a 24-to-1 transmission ratio that imparts a magnifying torque and allows ±50° of travel. Cables work better than a belt drive, which has elasticity and needs tensioning, Somes adds.
One button releases the servo control and allows an operator to move the arm. It opposes gravity by knowing the torque to apply and friction to hold the arm in place. The operation begins with the device locating the workpiece with contact measurements, using the material removal tool as the probe. It takes only seconds to determine a part’s height and location, and the CAD model mates to the touch point to determine the motion path.
Machining and grinding passes are made with optimal contact force. With part geometry determining the toolpath, the control software can identify the location and amount of excess material by comparing the tool trajectory to a CAD model reference. Tool trajectories generated automatically focus effort on the part until the measured surface contour matches the CAD specification. The system can deliver results despite process variations that can include part fixturing, the amount of material needing to be removed, and the changing size and efficiency of the material removal tool. Despite initial geometry and positioning variation, the material removal is accurate within a few tenths of a millimeter, due to the common datum reference between measurement and material removal. The absolute location of the workpiece is not important, only that the robot can discover it in the context of its material removal tool.
In the off mode, the robot disconnects the servo and brakes lock the arm in place, while software maintains the tool position.
Turbine blade finishing is challenging because the parts require perfect surface smoothness while tolerating the dimensional variations resulting from the casting process. The lack of easily referenced datum surfaces for locating tooling rules out machining to fixed coordinates. However, while part geometry varies widely, the casting artifacts requiring finishing are generally few, such as parting lines, pin blips, and core exit flash. The Touch Robot’s software predetermines strategies for addressing these features on a wide array of parts. An operator generates part programs by filling in blanks on sequential function blocks using a web browser. Manually guiding the robot and part to the desired positions identifies the material removal tool poses and transition waypoints. Areas requiring finishing are designated by annotations on the part’s CAD model within the software. Tool trajectories, contact forces, and performance metrics are dynamically generated at run time with the user-provided parameters, geometry derived from the CAD model, and self-acquired part measurements.
The Eastlake, Ohio foundry of Consolidated Precision Products (CPP) is the first company to use the Touch Robot to remove excess material on difficult-to-reach areas of tough, precision-cast turbine engine components.
The test project involved deflashing or opening up the trailing edge exits of a nozzle ring casting, with each APU disc containing 22 vanes. In grinding small turbine blades, it is tedious for operators to remove the excess material – the flash – so, the robot tracks the edge exit holes where flash needs to be removed. The robot determines contact point and pressure, touches off all 22 airfoils to establish the part height, then grinds away the flash in sequence so the tool is not always powering up and down. Machining removes material to within 0.005" leaving just a small excess for an operator to finish up.
“Since the robot knows where it is grinding – more than a person could control and repeat – you can use aggressive tools, not just abrasive stones,” Somes notes.
CPP makes multiple vane segments with different alloys, soft and hard, and they’re slightly different in size. The robot can distinguish differences in each by the way it cuts.
“This kind of contouring is not easy,” explains Albert Osagie-Erese, senior product engineer with CPP. “We needed a fixture and program to do what was required and Steve was able to develop a program and make it available to us.”
After Somes did a demonstration onsite, other workers were qualified on the robot.
“Two years ago, the workers finished approximately 150 castings per day,” Osagie-Erese says. “With the robot, they can do 175.”
Using a hand deburring tool alone on the 22-vane nozzle ring took 45 minutes to 1 hour, but by using the robot, that is now reduced to 20 minutes per part.
“It’s all about the cycle time,” says Somes. “Three operators can do the operation now, and without the wrist wear-and-tear, reducing repetitive motion injury.”
The production increase is timely, since the customer recently increased its ring nozzle order, up to 1,500 rings per year. “We can increase the number of parts finished without increasing staffing,” Osagie-Erese points out.
“Most robots can’t tell if tool is wearing, but as ours wears down it can calculate,” Somes says.
Cycle time goes up, and this tracks to the software. As a tools dulls, the software generates a 1-to-10 scale; when it drops to 3, it’s time to change it.
The carbide burrs with titanium coating now last for 30 or 40 parts, versus only one before. Dry machining with compressed air keeps tools running cooler, so now it’s possible to do two parts instead of just one-third-part per tool.
“From my point of view, this has been a successful project,” Osagie-Erese says.
Force Robots LLC
About the author: Eric Brothers is senior editor of Aerospace Manufacturing and Design and can be reached at 216.393.0228 or email@example.com.
Every day, millions of people log onto distributed computing systems and collaboratively design three-dimensional (3D) systems. But they aren’t CAD designers working on new facial reconstruction implants, diesel fuel rails, helicopter rotors, or wind turbine blades.
Gathering online to design buildings and cities, more than 100 million people worldwide are registered users of the low-resolution video game Minecraft. In early 2015, the pocket edition of the game for iOS and Android devices passed the 30 million download mark. Called by some the Legos of the 21st century, Minecraft is more than just a game, it’s a sign of where design is going.
Programmers of modern design software systems say Minecraft’s explosive popularity has shown that it can be easy to work across vast geographic distances using shared resources. Multiple players simultaneously work on the same overall design, watching as the changes one user makes ripple through the house or city that they’re building – a level of real-time collaboration that many professional design teams can’t achieve.
In practical terms, that means the days of designers managing their own files and working on discreet systems are numbered. The future is in connected, cloud-based offerings where designers’ different sub-systems will work from the same master files – a change in the basic architecture of the finished product will ripple through every component instantly instead of having to be reconciled against multiple, different versions.
“When we came off the drafting board into CAD, we were looking for ways to get rid of the roadblocks in design,” says Carl White, senior director of manufacturing engineering products at software provider Autodesk. “One of those last roadblocks is fitting different designs together. With the cloud, you’re not dealing with different designs. You have one version of the product, and everyone’s using that.”
Simulation in vehicles
Olivier Sappin, vice president of transportation & mobility industry, Dassault Systèmes, says functional mock-ups combined with simulation can reduce project latency by 3 years.
“It is 75% less expensive to do virtual crash-testing for cars and the benefit is huge because you can adapt from that analysis areas that didn’t work, and the engineers can fix and improve the design before the physical vehicle ever exists,” Sappin says.
PSA Peugeot Citroën engineers use DELMIA digital manufacturing applications to simplify the innovation process of its body-in-white division, primarily through right-first-time robotics planning.
Advanced robotics simulation, includes feasibility and reachability studies and programs. Efficient production layout complements final assembly simulation, painting, powertrain, and stamping.
To improve manufacturability of vehicle parts that include openings, panels, structures, and underbodies, PSA Peugeot Citroën used DELMIA Robotics simulation applications to avoid potential errors and collisions that can lead to material waste and production re-do. By integrating robotics simulation on the 3DEXPERIENCE platform, PSA Peugeot Citroën will increase its plant flexibility and fortify its modularization strategy by reinforcing standardization and production line reuse.
“Seamless, digital continuity between engineering and manufacturing, we believe is key to strengthen our overall business agility,” says Sébastien Gagnepain, process and digital factory coordinator, PSA Peugeot Citroën.
With design engineers working off of a single master file, opportunities open up throughout an organization says Ken Clayton, vice president of Dassault Systèmes’ 3DS professional channel. With that “one single view of the truth,” expanded opportunities could include:
Manufacturing engineers could study early design iterations, making sure that the styles and forms being considered can be cost-effectively built.
Materials specialists could look for opportunities to shave weight out of systems by replacing heavier materials with lighter ones. They could then test those alternative material choices with advanced simulations.
Purchasing managers could examine material costs for various parts, recommending less-costly alternatives for any exotic choices from designers.
Safety experts could examine potential designs for obvious flaws and begin use-and-abuse simulations.
Marketing and advertising departments could begin mocking up brochures and educational material early in the process.
Financial planners and fiscal executives can track the progress of a design through multiple departments, getting a much clearer picture on when to expect manufacturing and sales to begin.
“Our platform of 12 software applications covers 3D modeling (SOLIDWORKS, CATIA, GEOVIA, BIOVIA); simulation (3DVIA, DELMIA, SIMULA); social and collaboration (3DSWYM, 3DXCITE, ENOVIA); and information intelligence (EXALEAD, NETVIBES),” explains Monica Menghini, Dassault executive vice president and chief strategy officer. “These apps together create the experience. No single point solution can do it – it requires a platform capable of connecting the dots. And that platform includes cloud access and social apps, design, engineering, simulation, manufacturing, optimization, support, marketing, sales and distribution, communication (PR and advertising), PLM – all aspects of a business; all aspects of a customer’s experience.”
A lot has to change to achieve these goals. Corporate department structures typically don’t support having design engineers share information with sales/marketing and regulatory/safety departments. But technologically, says Dassault Systèmes’ vice president of design experience, Anne Asensio, there’s nothing preventing such a shift into more collaborative environments. The design process throughout an organization can speed up considerably because interested parties can have their say early in the process – reducing the need for rework and redesign when those great visual features turn out to be impossible to machine, or when components become a safety concern in crash testing.
Visualizing the human heart
Dr. Steve Levine developed The Living Heart Project for personal reasons; his daughter was born with reversed heart chambers. As chief strategy officer of Dassault Systèmes’ SIMULIA, Levine pushed for a 3D realistic simulation model of a whole human heart. The Living Heart Project was developed with a multidisciplinary team of heart experts to help combat cardiovascular disease. Levine notes that this is launching the next frontier in diagnosing, treating, and preventing heart conditions through personalized, 3D virtual models.
The Living Heart Project unites cardiovascular researchers, educators, medical device developers, regulatory agencies, and practicing cardiologists to develop and validate highly accurate personalized digital human heart models. These models will establish a unified foundation and serve as a common technology base for education and training, medical device design, testing, clinical diagnosis, and regulatory science – creating an effective path for rapidly translating current and future innovations directly into improved patient care.
With Levine’s lead, and personal connection, this project has ramped up fast.
Late last year at the company’s 3DEXPERIENCE Forum in Las Vegas, Bernard Charles, president and CEO, announced that the company had signed a 5-year collaborative research agreement with the FDA. Initially targeting cardiovascular devices used to treat heart disease, specifically testing device insertion, placement, and performance, development team sees this as a path to expediting the approval process of medical devices, spurring innovation, enhancing patient reliability, and reducing costs.
Part of the development team for The Living Heart Project is the Medical Device Innovation Consortium (MDIC) (www.mdic.org). Utilizing this collaborative approach for medical device advancements, 3D modeling brings a noninvasive approach to advance treatment without using patients for trial studies. http://goo.gl/NLGWXi
Putting master design files onto cloud servers is the first step toward that goal, and this is where experts say some designers resist a changing work environment.
Autodesk’s White says the big concern is not having direct access to files. Design engineers tend to be responsible for their designs, so the idea of other people fiddling with their creations doesn’t sit well.
“In a lot of cases, people aren’t being given much of a choice,” White says. “Decisions have to be made much faster in the market these days, so companies are adopting these tools. For us, the key is to make the designer comfortable. Everything has to be traceable. With every change, it has to be clear who made it and when.”
Getting other departments interested in having access to design files is a much easier task, he adds. “If corporate people can get more actionable data at their fingertips, they’re on board.”
Advances in simulation software have helped create demand within companies for more data sharing. Stress-testing or crash-testing products is an expensive process that generates very specific data, but physical testing is costly and has limitations. Virtual testing, on the other hand, is inexpensive and data rich, giving designers the ability to test a much wider range of iterations and concepts.
Eric DeHoff, principal engineer and computer-aided engineering technical leader for Vehicle Structures Research – Automotive Safety at Honda, says modern simulation software is so detailed it can “predict material fracture or spot-weld failures. Success is based on confidence in computer-aided engineering methods.” Dassault Systèmes’ 3Dxcite has grown from color-coded engineering renderings to scenes of photographic realism. “What took an expert 6 weeks before, a non-expert can do in 2 days.”
The simulated crash resembles a real crash, revealing what high-speed cameras on an actual car can’t. It can isolate the chassis or cabin, remove the collision barrier from the visualization, and show hidden components within structures, such as parts inside doors.
Engineers can substitute a single physical crash with dozens of simulated crashes to understand actual vehicle behavior, without the time or cost.
Autodesk’s White says photo-realistic, data rich simulation is the gateway feature that is encouraging more companies to seek holistic design software that combines what previously had been several discreet tools. Once companies start down that connected path, however, they begin to see more opportunities to work across departments and gain more value from their most important assets – the intellectual property stemming from design and engineering expertise.
Virtual reality design
Combined advances in processing speeds and display hardware have allowed some design and engineering departments to radically change how they approach the most basic part of the creative process – how the craftsman interacts with the virtual design.
David Markham, advanced programs vice president for Lockheed Martin Space Systems, says complete virtual design environments now allow engineers to interact more with designs in a three-dimensional space. Virtual reality design environments allow engineers to visualize completed systems, enable component designers to enlarge miniature components to see them act in real time, and give project collaborators greater opportunities to see how all pieces fit together.
“The Computer Assisted Virtual Environment (CAVE) lets us test ideas before committing costly resources. The full-surround environment can shorten the design process from months to days, allowing many prototypes to be imagined and quickly corrected in virtual space.” www.lmco.com
About the authors: Robert Schoenberger, Eric Brothers, and Elizabeth Engler Modic are editors of Aerospace Manufacturing and Design and can be reached at firstname.lastname@example.org, 216.393.0271; email@example.com, 216.393.0228; or firstname.lastname@example.org, 216.393.0264.