About

The overarching vision for the Center for Rapid Automated Fabrication Technologies (CRAFT) is to develop the science and engineering needed for rapid automated fabrication of objects of various size out of a variety of materials including polymers, metals and alloys, ceramics and composites such as concrete at various sizes ranging from meso-scale to mega-scale objects. Application areas for CRAFT technologies are diversified and include fields such as biomedical, automotive, space industry, and building construction industry. CRAFT develops a unique academic environment blending fundamental engineering research with the development of engineered systems; partnerships with materials, equipment, construction, architecture, real estate, software and manufacturing industries; incorporating environmental, regulatory, labor and economic expertise and interdisciplinary graduate and undergraduate education.

Research topics

• Computer Science
• Artificial Intelligence
• Materials science
• Geology
• Automotive engineering
• Engineering drawing
• Computer vision
• Composite material
• Engineering
• Mechanical engineering
• Process engineering

Selected publications

• INTELLIGENT MANUFACTURING BASED ON GENERATION OF ALTERNATIVE PROCESS PLANS

  2023-01-01 · 2 citations

  articleSenior author

  Process planning is one of the key activities for product design and manufacturing. Process plans developed in this activity fulfil several purposes: manufacturability evaluation of product design, cost justification of required processes, process and geometry data for NC programming, and process specification for resource planning, scheduling and actual manufacturing. Ability to consider and evaluate alternative plans during design and/or scheduling allows for better product design, lower cost and more efficient manufacturing. In this paper we describe the process plan network, a hierarchical model which allows other functions to select the most appropriate alternative representation for given conditions. The procedure for generation of the process plan network is explained and two algorithms for the selection of process plans in various stages of product development are presented. Several experimental results are shown. The process plan network consists of several levels: feature level, process level, tool direction level, machine level and plan level. Generation of network starts at the bottom level, from features and by considering alternative processes, tools and machines and clustering of processes into manufacturing activities the network is build toward its top. During the network generation a large set of ordering constraints between features, tools and machines is considered in order to produce set of alternative but feasible process plans. The selection of process plan from the network is performed according to some efficiency criteria. Two optimization algorithms are applied: space search and network optimization. The method for simultaneous network generation and plan optimization is also implemented. The efficiency of algorithms is described on several examples.

  PublisherDOI

• Sustainable Earthquake Resilience with the Versatile Shape Memory Alloy (SMA)-Based Superelasticity-Assisted Slider

  Sensors · 2022-09-12 · 8 citations

  articleOpen access

  Earthquakes threaten humanity globally in complex ways that mainly include various socioeconomic consequences of life and property losses. Resilience against seismic risks is of high importance in the modern world and needs to be sustainable. Sustainable earthquake resilience (SER) from the perspective of structural engineering means equipping the built environment with appropriate aseismic systems. Shape memory alloys (SMAs) are a class of advanced materials well suited for fulfilling the SER demand of the built environment. This article explores how this capability can be realized by the innovative SMA-based superelasticity-assisted slider (SSS), recently proposed for next-generation seismic protection of structures. The versatility of SSS is first discussed as a critical advantage for an effective SER. Alternative configurations and implementation styles of the system are presented, and other advantageous features of this high-tech isolation system (IS) are studied. Results of shaking table experiments, focused on investigating the expected usefulness of SSS for seismic protection in hospitals and conducted at the structural earthquake engineering laboratory of the University of Bonab, are then reported. SSS is compared with currently used ISs, and it is shown that SSS provides the required SER for the built environments and outperforms other ISs by benefitting from the pioneered utilization of SMAs in a novel approach.

  PublisherOA PDFDOI

• Real-time extrusion quality monitoring techniques for construction 3D printing

  Construction and Building Materials · 2021 · 62 citations

  Senior authorCorresponding
  • Computer Science
  • Automotive engineering
  • Process engineering
  PublisherOA PDFDOI

• Automated inspection in robotic additive manufacturing using deep learning for layer deformation detection

  Journal of Intelligent Manufacturing · 2020 · 96 citations

  Senior authorCorresponding
  • Artificial Intelligence
  • Computer Science
  • Artificial Intelligence
  PublisherOA PDFDOI

• Performance-Based Testing of Portland Cement Concrete for Construction-Scale 3D Printing

  Elsevier eBooks · 2019-01-01 · 39 citations

  book-chapterOpen accessSenior author
  PublisherOA PDFDOI

• Water Unloading of Gas Wells Using the Concurrent-Water-Collection Method

  SPE Production & Operations · 2019-04-05 · 1 citations

  article1st authorCorresponding

  Summary In this paper we describe a novel method for water unloading of natural gas wells in mature reservoirs experiencing low reservoir pressures. Current methods for water unloading from gas wells have at least one of the drawbacks of restricting gas production, requiring external energy, using consumable surfactants, or being labor intensive. The proposed design offers a new approach to water unloading that does not restrict or interrupt gas production. It can operate without external energy, and uses no consumables. Virtual and physical simulators have been developed and the full-scale version of the concept has been studied in test wells to demonstrate the feasibility and performance of the new water-unloading concept. An industrial-grade preproduction prototype was tested successfully in a test gas well to validate this study.

  PublisherDOI

• Computer vision for real-time extrusion quality monitoring and control in robotic construction

  Automation in Construction · 2019-02-01 · 155 citations

  articleOpen accessSenior author
  PublisherOA PDFDOI

• List of Contributors

  Elsevier eBooks · 2019-01-01

  book-chapter
  PublisherDOI

• A Framework for Performance-Based Testing of Fresh Mixtures for Construction-Scale 3D Printing

  Rilem bookseries · 2018-08-29 · 8 citations

  book-chapterOpen accessSenior author
  PublisherOA PDFDOI

• The Disruptive Technology that is Additive Construction: System Development Lessons Learned for Terrestrial and Planetary Applications

  2018 AIAA SPACE and Astronautics Forum and Exposition · 2018-09-15 · 16 citations

  articleOpen accessSenior author

  Disruptive technologies are unique in that they spawn other new technologies and applications as they grow. These activities are usually preceded by the question, "What If?" For example, "What if we could use an emerging technology and in-situ materials to promote exploration on the Moon or Mars, and then use that same technology to keep our troops out of harm's way and/or help the worlds' homeless?" This question allows us to flip the mindset of "how can people create more valuable innovation?" to "how can innovation create more valuable people?." This approach allows us to view augmented human labor as an inclusive opportunity, not a threat. The discipline of Additive Construction is growing rapidly due to the flexibility, speed, safety and logistics benefits offered as compared to standard construction techniques. Additive construction is a disruptive technology in that it employs the principles of additive manufacturing on a human habitat structure scale. Developed initially for emergency management and disaster relief applications, additive construction has now grown into military infrastructure and planetary (Moon and Mars) surface infrastructure applications as well. Additive Construction with Mobile Emplacement (ACME) is a NASA technology development project that seeks to demonstrate the feasibility of constructing shelters for human crews, and other surface infrastructure, on the Moon or Mars for a future human presence. The ACME project will allow, for the first time, the 3-dimensional printing of surface structures on planetary bodies using local materials for construction, thereby tremendously reducing launch and transportation mass and logistics. Some examples of infrastructure that could be constructed using robotic additive construction methods are landing pads, rocket engine blast protection berms, roads, dust free zones, equipment shelters, habitats and radiation shelters. Terrestrial applications include the development of surface structures using Earth-based materials for emergency response, disaster relief, general construction, and housing at all economic levels. This paper will describe the progress made by the NASA ACME project with a focus on prototypes and full scale additive construction demonstrations using both Portland cement concrete and other indigenous material mixtures. Rationale for the use of additive construction for both terrestrial and planetary applications will be explored and a thorough state-of-the-art of additive construction techniques will be presented. An evolutionary history of NASA's additive construction development efforts, dating back to 2004, will be included. The paper will then step through a series of trade studies performed to inform key processing and design decisions in the development of the full-scale ACES-3 system developed by NASA and the Jacobs Space Exploration Group for the U.S. Army Corps of Engineers (USACE) Construction Engineers Research Laboratory (CERL) in Champaign, IL. The selection of aggregate and binders, based on in-situ materials, will also be presented and discussed

  PublisherOA PDFDOI

Recent grants

• Digital Fabrication of High-Temperature Metals Using Selective Inhibition of Sintering

  NSF · $450k · 2011–2016

• AIR Option 1: Technology Transition - Commercialization of Additive Manufacturing of Metallic Parts Using Selective Inhibition from Sintering

  NSF · $184k · 2013–2017

Frequent coauthors

• Xiao Yuan

  Peking University

  20 shared

• Ali Kazemian

  15 shared

• Dušan Šormaz

  Ohio University

  14 shared

• Madhu Thangavelu

  Southern California University for Professional Studies

  10 shared

• Bahram Asiabanpour

  7 shared

• Anders L. Carlson

  7 shared

• Iraj Ershaghi

  University of Southern California

  7 shared

• Dooil Hwang

  Southern California University for Professional Studies

  7 shared

Education

• Ph.D., Mechanical Engineering

  University of California, Los Angeles

  1983

• M.S., Mechanical Engineering

  University of California, Los Angeles

  1979

• B.S., Mechanical Engineering

  University of Tehran

  1977

Awards & honors

• 2011 NASA NASA NIAC Fellow
• 2006 National Inventor's Hall of Fame, History Channel, Time…
• 2005 School of Engineering Senior Research Award
• 2005 Oklahoma State University Pete Lohmann Medal
• 2005 Society for Computer Simulation Fellow of the Society f…