(Old)
We have seen that hard automation generally involves mass-production machines that lack flexibility. In soft automation (also called flexible or programmable automation) greater flexibility is achieved through the use of computer control of the machine and or its functions; thus it, can produce parts having complex shapes. Soft automation is an important development, because the machine can be reprogrammed easily and readily to produce a part that has a shape or dimensions different from the one produced just prior to it. Further advances in flexible automation include the extensive use of modern computers leading to the development of flexible manufacturing systems with high levels of efficiency and productivity.
(Kalpakjian S., Schmid S.R., Manufacturing engineering and technology, pg 1151)
(New and Better)
Flexible automation utilizes computers to control the flow of material, process, software and products across the manufacturing floor physically. the flow of software is included in the list (and in the system design and implementation) to ensure that programs and schedules may be dynamically changed to meet the requirements changing products or product mix.Another prerequisite to the implementation of soft automation is in the choice of machinery, transfer mechanism and the connectivity between production centers. Early implementations manifest themselves as Flexible-Manufacturing Centers (FMC), or Flexible-Manufacturing Systems (FMS) which describe the flexible automation of individual production centers as islands of automation. More ambitious undertaking of flexible automation deal with complete production lines and are represented by Flexible Transfer Lines. The advance in flexible automation further empehsize the need to break the barriers between CAD and CAM, to facilitate fast flow of NC programs representing new products or engineering changes.
(Handbook of Design, Manufacturing and Automation, Richard C. Dorf, pg. 126)
Tactile Sensing (Robotics, Sensors)
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Tactile sensing is the continous sensing of variable contact forces, commonly by an array of sensors. Such a system is capable of performing within an arbitrary three-dimensional space. Fragile parts (such as glass bottles and electronic devices) can be handled by robots with compliant (smart) end effectors. These effectors can sense the force applied to the object being handled using piezoelectric devices, strain gages, magnetic induction, ultrasonics and optical systems of fiber optics and light-emitting diodes. (Kalpakjian S., Schmid S.R.,Manufacturing engineering and technology, p. 1173)(New, Better)A tactile sensor is defined to be a device which measures parameters of a contact interaction between the device and some physical stimulus (Nicholls, 1992). The interaction is normally confined to a touch sensitive region of the devices surface.Tactile sensors provide data that is input to a computing system, and the acquisition, processing, and manipulation of this data constitutes tactile sensing. Some researchers limit the definition of the tactile sensing to the measurement of the forces at a set of discrete sites (e.g., Harmon, (1984)), but this is a rather restrictive definition; there are various examples of sensing through touch that detect properties other than force (e.g., 3D shape (Sato et al, 1986) and thermal conductivity (Russell, 1988)) and so a wider definition is used here.Tactile sensors are used to sense a diversity of properties concerning both attributes of a contacting stimulus and the relationship between the stimulus and sensor. Such a sensor may simply detect presence or absence of touch, whilst a more complex tactile sensor may provide data on the size, shape, position, thermal conductivity or distribution of forces of a contacting object.
(Intelligent Assembly Systems, M.H. Lee, pg 133)
Analytical Prototype (Prototyping, Design)
(Old)
Analytical prototypes represent the product in a non-tangible, usually mathematical or visual, manner. Interesting aspects of the product are analyzed, rather than built. Examples of analytical prototypes include computer simulations, systems of equations encoded within a spreadsheet, and computer models of three-dimensional geometry.
(Kalpakjian S., Schmid S.R.,Manufacturing engineering and technology, 5th Edition, page 247)
(New and Better)
Analytical prototypes are usually mathematical models of the product. They can only exhibit behavior arising from explicitly model phenomena. However, some behaviors are not always anticipated, as bridge building, and airplane builders have learned the hard way. Some of the behaviors maybe artifact of the analytical method, but the big advantage is that analytical approaches can allow more experimental freedom than physical models. Above all it is important to realize that one prototype is seldom enough. it is important to understand that virtually every industry has its own prototyping phases and processes.
(Entrepreneurship, Ellen L. Carsrud, pg. 68 )
STEP (Data Exchange Standards)
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STEP is acronym of The Standard for the Exchange of Product Model Data , is a wide and strong set of ISO (International Organization for Standardization) standards, all under ISO 10303. The overall objective of STEP is to provide a mechanism that describes a complete and distinct product explanation throughout the life cycle of a product. STEP provides both generally convenient data modelling methods and data models focused on specific industrial uses. The STEP standards contain numerous dozen separate documents. STEP advanced from earlier efforts in building data standards for CAD, particularly the Initial Graphics Exchange Specification (IGES), the first version of which was released in 1980.
(Andrew Y.C. Nee, Xun Xu; Advanced Design and Manufacturing Based on STEP; Page: 1)
(New and Better)
STEP is the acronym for the standard for the exchange of the product model data, which are serials of International standards codified as ISO 10303. STEP is being developed to enable complete and correct interchange of product data between various CAD/CAM systems, other manufacturing related software, and vendors (Jordon, 1994). It was formally published in 1994 and it is now widely accepted by academic researchers, system vendors, and industrial experts.
The scopes of STEP are (ISO 1994-1:1994(E)):
- The representation of product information, including components and assemblies.
- The exchange of product data, including storing, transferring, accessing and archiving.
(Rapid One-Off-A-Kind Product Development: Strategies, Algorithms and Tools, Shane Xie, pg 72)
Virtual Prototyping (Virtual Reality, Prototyping, Manufacturing)
(Old)
Based on virtual reality technology, involves the use of the CAD geometric model to construct a digital mock-up of the product, enabling the designer and others to obtain the sensation of the real physical product without actually building the physical prototype. Virtual prototyping has been used in automotive industry to evaluate new car style designs. The observer of the virtual prototype is able to assess the appearance of the new design even though no physical model is on display. Other applications of virtual prototyping include checking the feasibility of assembly operations, for example, parts mating, access and clearance of parts during assembly, and assembly sequence.
(Groover, M.P., Automation, Production Systems and Computer - Integrated Manufacturing, pg.704, Pearson Education Inc,2008)
(New and better)
An obligatory stage in the development of a new product is a prototype, is first physical realization. This stage validates the design, establishes manufacturing methods and determines how easy to use (or ergonomic) the product is. Often prototype realization uncovers design mistakes and thus it maybe iterative. The more complex the product the more expensive its physical mockup. Especially when several new versions need to be constructed.
As instance when prototypes are extremely expensive occurs in aircraft and automotive manufacturing. A new car model mockup, for example, is realized to study the visual effect of a designers' concept. It is made of clay at full scale, painted to look like a real car, and may cost 1 million dollars to realize. It is thus not surprising that aircraft and car manufacturers have been pioneers in the introduction of the virtual prototyping. As a way to replace the more expensive physical counterpart. Apart from cost savings, virtual prototypes have the advantages of flexibility (It is easier to change software than build a new physical mockup), online documentation, and the ability to view remotely (for design approval and marketing).
(Virtual Reality Technology, Vol 1, Gregore Burdea, pg. 350-351)
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