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Broad Considerations for Sustainable Engineering - Richard Wysk, North Carolina State University


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Richard Wysk, North Carolina State University - Speaker at the marcus evans Manufacturing COO Summit 2012, held in Las Vegas, NV, April 16-17, 2012, delivered his presentation entitled Broad …

Richard Wysk, North Carolina State University - Speaker at the marcus evans Manufacturing COO Summit 2012, held in Las Vegas, NV, April 16-17, 2012, delivered his presentation entitled Broad Considerations for Sustainable Engineering

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  • 1. Some broad considerations for  sustainable engineering i bl i i Richard A. Wysk Dopaco Distinguished Professor Industrial and Systems Engineering y g g North Carolina State University  1
  • 2. Agenda• Sustainability   ‐‐ a brief overview• Sustainability from an engineering perspective Sustainability from an engineering perspective – This could be the world’s most difficult  engineering problem g gp• What’s new in the manufacturing world? – Direct manufacturing (DM) and hybrid Direct manufacturing (DM) and hybrid  manufacturing (HM)• New directions in DM, HM and sustainability y• Observations and conclusions 2
  • 3. Why Engineer for Sustainability? Why Engineer for Sustainability?• Should be considered as part of a concurrent  p engineering team effort.• 80% of the environmental damage of a product is  established after 20% of the design activity is  bl h d f f h d complete.• Business case analysis Business case analysis – Customers demand products with less environmental  impact,• Governmental agencies are developing and enforcing  tighter regulations.
  • 4. Pay me now or pay me laterPay me now or pay me later
  • 5. A Vision of Sustainable Engineering  Systems 
  • 6. Environmental Objectives Environmental Objectives• Protect the biosphere Protect the biosphere – Minimize the release of pollutants that endanger the  earth.• Sustainable use of resources – Use raw materials at a level where they can be  sustained.• Reduction and disposal of waste – Minimize waste wherever possible. When waste  cannot be avoided, recycling will be adopted.
  • 7. Environmental Objectives Environmental Objectives• Wise use of energy Wise use of energy – Use environmentally safe energy and invest in  energy conservation. energy conservation• Risk reduction – Minimize health risk to employees and the Minimize health risk to employees and the  community.• Marketing of safe products and services Marketing of safe products and services – Sell products that minimize environmental  impact and are safe for consumers to use.
  • 8. Life Cycle Assessment Life Cycle Assessment• Common methodology Common methodology – Society of Toxicology and Chemistry (SETAC) has  developed a 4 step process for completing a Life  developed a 4‐step process for completing a Life Cycle Assessment (LCA). • Cradle to grave assessment. • Dependent on large amounts of data. • Steps: Goal Definition, Environmental Impact Inventory,  Impact Assessment, Interpretation.
  • 9. What Is Life‐Cycle Assessment (LCA)?  LCA i a analytical f is l ti l framework used t examine, id tif and k d to i identify, d evaluate the energy, resource, and environmental implications of a process, product, or system across its life span from cradle to grave. Linear View of Products Raw Material Acquisition and Processing Raw Material Acquisition and Processing Manufacturing g Use DisposalSource: EPA (2006) – LCA: Principles and Practice Courtesy of Ranji Ranjithan
  • 10. Inventory AnalysisInventory Scope Inventory Product Life StagesPrimary  AirborneMaterials Raw Material Acquisition and Processing Emissions ManufacturingSecondary  Waterborne MaterialsM i l Emissions E i i Recycling Reuse Use Energy  Other  End of Life Management Releases Use a SCOR Model to determine how this works in a Courtesy of Ranji Ranjithan PLAN,SOURCE, MAKE, DELIVER, and RETURN environment
  • 11. Techniques to Reduce Environmental Impact q p Design to minimize material usage• Material usage – Packaging and distribution • Programs to accept back packaging (computers) – Production system • Ex.: plastic body panels (Chrysler) that require no paint ( ) – Product • Minimize “high impact” materials Minimize  high impact materials • Increase use of materials that can be processed together • Can different polymers be remelted together (e.g.  compatibility)? 
  • 12. Techniques to Reduce Environmental Impact           Techniques to Reduce Environmental Impact Design for Disassembly• Guidelines similar to DFA.• Some key differences: Some key differences: – Snap‐fit design (integral fasteners) must work  during removal as well as insertion should a part  during removal as well as insertion should a part be needed for remanufacturing. – For recycling only “tearing apart” is of interest. – Must consider ergonomics and time. Disassembly  time may be very different than assembly time.
  • 13. Techniques to Reduce Environmental Impact           Techniques to Reduce Environmental Impact Design to Recycling• Primarily material choice. Recycling Rate (%)• Typical materials recycled in US 1993 2006 – High density polyethylene (HDPE) 10.6   26  – Polyethylene terephthalate (PET) 18.0   24 – Low‐density polyethylene (LDPE) 1.9    1 – Polypropylene (PP) 1.5    9 – Polyvinyl chloride (PVC) 0.8     1
  • 14. Techniques to Reduce Environmental Impact           Techniques to Reduce Environmental Impact Design to Recycling• Other recycling: – Gl ( Glass (can lower heat needed to melt) l h t d dt lt) – Metal chips – Paper (ask McDonald’s!) ( k ld’ !)• New technologies – Chips or identifiers to automatically recycle (auto  industry)
  • 15. Styrofoam  A problem?!?Styrofoam – A problem?!?
  • 16. Short term answers Short‐term answers• Compacting reduces volume Compacting reduces volume• Doesn’t really eliminate the  problem
  • 17. Techniques to Reduce Environmental Impact             New Technologies N T h l iPolystyrene FoamRecycling SystemEmploying LimoneneSony
  • 18. Techniques to Reduce Environmental Impact          Techniques to Reduce Environmental Impact Design to minimize hazardous materials• Functionally equivalent materials can have  a large impact on the environment. a large impact on the environment. – Ex.: switch from using polystyrene to less‐ impacting plastics such as high density  polyethylene (recycled at much higher rate) • No impact on design performance.• Ch i l t Chemicals to avoid id• Material impact comparisons – Must also consider cost differences.
  • 19. Techniques to Reduce Environmental Impact             Design for energy efficiency• Reduce energy consumption of product – Specify best‐in‐class energy efficient components (air  conditioners, refrigerators) – Have subsystems power down when not in use (copiers) – Permit users to turn off systems in part or whole Permit users to turn off systems in part or whole – Solar‐powered electronics (calculators) – Vibration harvesting – Insulate heated systems y – Make parts whose movement is powered as light as possible  (autos, planes) • New materials and processes give many new opportunities • Must be qualified and accepted; designers must understand how to Must be qualified and accepted; designers must understand how to  design with them (“design rules”); may limit suppliers • Buy to fly (Can be 200:1) • 100 pounds can mean 2% in MPG
  • 20. Supportability Considers Total System  “Cost of Ownership” “ f h ” Mike Battaglia;
  • 21. Okay, so this has been going on for a  decade or more.  What’s next? d d h ’• Changes in reclamation • More efficient methods• Changes in manufacturing • New paradigms • Changes in design Changes in design • Unconventional geometries• Changes in materials • Composites (higher strength to weight ratio) Composites (higher strength to weight ratio) • Up to 2% gas reduction per 100 pounds• Materials usage efficiency • 200:1 buy to fly ratio
  • 22. Something very newSomething very new
  • 23. A New Prosthetic Arm A New Prosthetic Arm• Titanium for  efficiency/medical  compatibility• Mesh structure• Weighs about 4  pounds• Can change the life  of a limb amputee p
  • 24. Impossible to build without additive  methods h d
  • 25. Functional using mechanical switchingFunctional using mechanical switching
  • 26. Medical/Dental/ Veterinary Applications V i A li iMarch 24 2006 (Chicago) -- The number of 24,total knee replacements performed in theU.S. will leap by 673% -- reaching 3.48million -- b th year 2030, according to a illi by the 2030 di tnew study presented at the 73rd annualmeeting of the American Academy ofOrthopaedic Surgery in Chicago.Hip replacements will increase by 174% to572,000 by 2030, according to the newfindings, which are based on historicalprocedure rates from 1990 to 2003, and on d t f t 2003 dpopulation projections from the U.S. CensusBureau.
  • 27. Direct Manufacturing Direct Manufacturing• Producing a product directly Producing a product directly  from a descriptive model. – In the mechanical part domain In the mechanical part domain,  taking a CAD model and directly  manufacturing a part g p
  • 28. Additive Manufacturing• Direct Manufacturing (DM) – Direct from CAD model without tooling Direct from CAD model without tooling • No process engineering – Short lead time – I Increased product fidelity d d t fid lit – Ready to use end products• Additive processes Additive processes Painted SLA Consumer Goods Part – Traditional Rapid prototyping (RP) process • 3D printer, SLA, FDM, SLS, SLM, EBM… – No geometry limitation – Push button manner operation – Restricted in material, accuracy, and surface finish , y, 28
  • 29. Electron Beam Melting (EBM) Electron Beam Melting (EBM)• Electron Beam Melting (EBM) is a type of rapid  Electron Beam Melting (EBM) is a type of rapid prototyping for metal parts. The technology  manufactures parts by melting metal powder layer  per layer with an electron beam in a high vacuum.  Unlike some metal sintering techniques, the parts  are fully solid, void‐free, and extremely strong.  Electron Beam Melting is also referred to as  Electron Beam Machining.• High speed electrons .5‐.8 times the speed of light  are bombarded on the surface of the work material  b b d d th f f th k t i l generating enough heat to melt the surface of the  part and cause the material to locally vaporize.  EBM does require a vacuum, meaning that the  workpiece is limited in size to the vacuum used. is limited in size to the vacuum used.  The surface finish on the part is much better than  that of other manufacturing processes. EBM can be  used on metals, non‐metals, ceramics, and  composites.
  • 30. Current directions in Manufacturing  Current directions in Manufacturing – Additive Manufacturing Selective Laser  Selective LaserElectron Beam  Melting Processes Melting (EBM) (SLM) 30
  • 31. Some other EBM partsSome other EBM parts 31
  • 32. EBM and Selective Laser Melting (SLM)  EBM and Selective Laser Melting (SLM)• Produces parts to about  casting quality directly from a  CAD model• Does not have the geometric  limitations of casting limitations of casting – Draft, parting line, etc.• Materials properties are Materials properties are  getting close to cast quality 32
  • 33. State of the Art for AM State of the Art for AM• Push bottom process – no process engineering Push bottom process  no process engineering  component• Functional metals are now being produced Functional metals are now being produced• Net‐shape or near net‐shape parts can be  produced d d• Geometrically few limits, except for precision 33
  • 34. Recent directions in Rapid Manufacturing ‐‐ Subtractive CNC‐RP Method:  A model is machined on a 3‐Axis mill with an  CNC RP Method: A model is machined on a 3 Axis mill with an indexer and tailstock using layer‐based toolpaths from numerous  orientations about an axis of rotation.   Small diameter flat‐end mill tool Round stock, fixed  between chucks b t h k 4th‐axis indexer Tailstock 34
  • 35. CNC RP Methodology CNC‐RP Methodology STEPS TO CREATE A PART ( MT. Bike Suspension Component) (Side View)1. First orientation of part section is machined 3. Third o e a o is machined 3 d orientation s ac ed Rotate Stock2. Second orientation is machined 4. Fourth orientation is machined 35
  • 36. CNC‐RP Methodology STEPS TO CREATE A PART ( MT. Bike Suspension Component)5. Left support section is machined 7. Temporary supports are removed 8. Part is severed from stock at supports6. Right support section is machined 36
  • 37. CNC RP Methodology CNC RP Methodology• Creation of complex parts using a series of thin layers  (slices) of 3‐axis toolpaths ( li ) f 3 i t l th generated at numerous  t d t orientations rotated about an axis of the part• Toolpath planning based on “layering” methods used by  other RP systems• “Slice” represents visible cross‐sectional area to be  machined about (subtractive) rather than actual cross  machined about (subtractive) rather than actual cross section to be deposited (additive)• Slice thickness is the depth of cut for the 2½‐D toolpaths• T l Tool used is a flat end mill cutter with equal flute and  d i fl t d ill tt ith l fl t d shank diameter (or shank diameter < flute diameter)• Stock material will be cylindrical, therefore toolpath z‐zero  location will be same for all orientations 37
  • 38. Methodology (cont.) Methodology (cont )Flat end mill cutter “Staircase” effect Region not visible from  bl f current orientation Set of visible slices from  current orientation Toolpath planning using this approach is done with ease in current CAM  Toolpath planning using this approach is done with ease in current CAM software (MasterCAM rough surface pocketing) 38
  • 39. Fixture Planning• Approach uses “sacrificial supports” to retain the prototype within the  stock material• Round stock clamped between opposing chucks• As prototype is rotated b/w toolpaths sacrificial supports are  incrementally created• Supports cut away to remove finished part• Current approach assumes model surfaces exist along axis of rotation – Only one fixture support cylinder used on each end – No change to visibility calculations 39
  • 40. Some other CNC RP partsSome other CNC‐RP parts (e) (f)(a) (d) (b) (g) (h) (c) 40
  • 41. A broad comparison A broad comparisonCharacteristic EBM Casting Machining CNC‐RPGeometry y Very good yg Fair Good GoodTolerance/SF Fair Fair Very Good GoodEnergy Fair(Part specific) Very Good Very Good GoodSet up cost Very good Fair Fair (Part specific) Very good 41
  • 42. Is it possible to get the best of both additive and  subtractive manufacturing? b i f i ?A hybrid EBM and CNC‐RP system 42
  • 43. It would be nice to ..It would be nice to .. 43
  • 44. Zeus • Zeus, a Siberian Husky  with a missing front paw• First patient with front  limb amputation• Different design needed  for the attachment 
  • 45. Combining Additive and Subtractive ProcessingCombining Additive and Subtractive Processing CAD model Part with CNC RM fixtures STL model for EBM  RP process. EX:  with all sacrificial  EBM supports CNC‐ RM Process Identify functional  Part for CNC RP  Part from RP  surfaces with supports process  Final part from  AIMS  45
  • 46. EBM MethodologyEBM Methodology 46
  • 47. And ..And ..
  • 48. So where is our future headed? So where is our future headed?• Design rules will change significantly Design rules will change significantly – We will not be limited to the use of solid  mechanical components for high performance  mechanical components for high performance products 48
  • 49. Our future … Our future …• Manufacturing cost and energy needs to be Manufacturing cost and energy needs to be  viewed/justified using operational costs as  well as production cost well as production cost – Possibility of eliminating more than 50% of the  product weight product weight
  • 50. For instance For instanceMagnus René, CEO of Arcam.Magnus René CEO of Arcam 50
  • 51. Non dense mesh parts Non‐dense mesh parts• Hi h h Higher shear parts can  t be obtained with less  material t i l• Better strength/weight  ratios can be gotten ti b tt• Directional mechanical  properties can be  ti b obtained
  • 52. Issues
  • 53. Conclusions• We are entering a new paradigm for engineering – P d Product engineering, Process engineering, production engineering  i i P i i d i i i are changing – We need to address these engineering functions in an integrated  manner• We have the ability to alter the use performance  characteristics of all future mechanical products p – Strength to weight ratio – Buy to use ratio – Sustainability product responsibilities Sustainability product responsibilities 53