1.
Playback Robot (robot control)
Old answer
An operator leads or
walks the playback robot and its end effectors through the desired path; in
other words, the operator teaches the robot by showing it what to do. The robot
records the path and sequence of motions and can repeat them continually without
any further action or guidance by the operator.
Another
type is the teach pendant, which utilizes hand-held button boxes that are
connected to the control panel; they are used to control and guide the robot
and its tooling through the work to be performed. These movements then are
registered in the memory of the controller and are reenacted automatically by
the robot whenever needed.
(Kalpakjian S., Schmid S.R., Manufacturing
engineering and technology, p. 1169)
New (better)
22.9
ROBOT CONTROL SYSTEMS
...
22.9.2
Playback Robot with Point-to-Point (PTP) Control
The controller has a memory for
recording not only the sequwncw of the motions in a given work cycle, but also
the locations that are associated with each element of the motion cycle. These
locations and their sequences are programmed into memory, and subsequently
played back during the operation. In PTP control, individual positions of the
robot arm are recorded into memory. These positions are not limited to the
mechanical stops set for each joint as in the caseof limited sequence robots.
Feedback control is used during the motion cycle to ascertain that the
individual joints have achieved the desired locations defined in the program.
22.9.3
Playback Robot with Continuous Path Control
Servo control is used to maintain
continuous control over the position and speed of the manipulator. A playback
robot with continuous path control has the inherent capacity for PTP control as
well. In a continious path motion, the movement of the arm and wrist is
controlled during the motion.
(Cad/Cam: Concepts And
Applications, Chennakesava R. Alavala, p. 467-468)
(Dorf, R.C., Kusiak, A., Handbook of Design, Manufacturing and Automation, 1994, John Wiley & Sons, Inc.,pg. 124-125)
(Proceedings of
the National Conference on Advanced Manufacturing & Robotics, S. N. Shome, p. 248-249)
3. Safety Stock (production planning)
Old answer (better)
(Supply chain management with
APO: structures, modelling approaches, and implementation
of myCAP, Jörg Thomas Dickersbach, p.416)
4. Carbon Black(material)
Old Answer
Carbon Black
This is a material of major significance to the rubber industry, so it is no surprise that most rubber products we see in the market place are black in color. We have moved a long way from collecting carbon from smokey oil flames, which produced a material called lampblack. The next historical step was to burn natural gas against iron channels, then scrape off the carbon to produce a highly reinforcing material called channel black. Both the use of this black in the rubber industry and its source of supply is currently limited and its cost is somewhat high. There are two common methods of producing carbon black today. Heating natural gas in a silica brick furnace to form hydrogen and carbon, produces a moderately reinforcing material called thermal black. Alternatively, if we incompletely burn heavy petroleum fractions, then furnace blacks are produced. These are the most important blacks in terms of quantity used and available types.
(Andrew Ciesielski, An Introduction to Rubber Technology, pg.37-38)
New (better)
2.8.2 Carbon Black
Carbon black production is a significant modern industry. Carbon blacks are formed by the incomplete combustion or cracking of hydrocarbon gases and vapors derived from petroleum sources (Taylor, 1997; Sebok and Taylor, 2001) and are classified as furnace blacks(<50 nm diameter), acetylene blacks (40-55 nm diameter) and thermal blacks (100-500 nm diameter). Manufacturers of carbon blacks produce at least 70 products designed for specific applications.
Donnet and Voet (1976) report major differences in surface areas of carbon blacks as determined by TEM (Stem) and by adsorption of nitrogen at 77 K (Sbet). Differences between the two surface area values are due to (a) the precence of microporosity with the carbon black particle and (b) to capillary condensation of the nitrogen adsorbate (77 K) occuring between the carbon black particles which are close packed. On the other hand, for Spheron 6, values of Stem and Sbet both equal to 106 (m^2)/g, making this carbon black (and its graphitized product Graphon) suitable for adsorption studies of carbon surfaces.
5. Sandwich Molding (manufacturing method)
Old Answer (better)
Sandwich Molding
Sandwich molding involves injection of two separate polymers - one is the outer skin of the part and the other is the inner core, which is typically a polymer foam. A specially designed nozzle controls the flow sequence of the two polymers in the mold. The sequence is designed so that the core polymer is completely surrounded by the skin material inside the mold cavity. The final structure is similar to that of a structural foam molding. However, the molding possesses a smooth surface thus overcoming one of the major shortcomings of the previous process. In addition, it consists of two distinct plastics, each with its own characteristics suited to the application.
(Groover, M.P., Fundamentals of Modern Manufacturing: Materials, Processes, and Systems, 4th Edition, p.294)
New
9.1 Coinjection (Sandwich) Molding
Coinjection molding (sometimes called "sandwich molding") comprises sequential and/or concurrent injection of a "skin" material and a dissimilar but compatible "core" material into a cavity. This process produces parts that have a sandwich structure, with the core material embedded between the layers of the skin material. This innovative projess offers the inherent flexibility of using the optimal properties of each material to reduce the material cost, injection pressure, clamping tonnage, and residual stress to modify the property of the molded part, and/or to achieve particular engineering effects.
(Injection Molding Handbook, Tim A. Osswald, p. 376)
2.
Feature-Based Design (design method)
Old answer
Feature-Based
Design
The consept of feature-based design was advanced as an attempt to simplify mechanical process design as an extension of CAD. In this approach, a mechanical design consists of a collection of standard geometric features, accompanied by standard processes to create these features. The list of such features includes prismatic shapes, cylinders, cones, slots, holes, rounds, fillets, etc. The potential of this approach was found to be limited since in many situations it is difficult, if not impossible, to describe a mechanical design in terms of a limited set of standard geometric features.
The consept of feature-based design was advanced as an attempt to simplify mechanical process design as an extension of CAD. In this approach, a mechanical design consists of a collection of standard geometric features, accompanied by standard processes to create these features. The list of such features includes prismatic shapes, cylinders, cones, slots, holes, rounds, fillets, etc. The potential of this approach was found to be limited since in many situations it is difficult, if not impossible, to describe a mechanical design in terms of a limited set of standard geometric features.
(Dorf, R.C., Kusiak, A., Handbook of Design, Manufacturing and Automation, 1994, John Wiley & Sons, Inc.,pg. 124-125)
New (better)
2. Feature Based Design
Feature based design is the technique of using features to create the mechanical model and use it further for downstream applications. This approach plays an important role to interface between CAD/CAPP/CAM. It is used to generate process plan automatically and hence to schedule manufacturing activities. The advantages of feature based design over conventional CAD approaches are the following.
1. It provides the ability to capture design intent and better understanding of the product geometry.
2. A means for designers to abstract the level of design by working with high level shapes along with other parameters for downstream applications instead of geometric details alone.
3. It encourages towards standardization leading to improvement in manufacturability and product quality.
4. It provides an easy method for modelling the mechanical engineering components with information on the downstream applications.
2. Feature Based Design
Feature based design is the technique of using features to create the mechanical model and use it further for downstream applications. This approach plays an important role to interface between CAD/CAPP/CAM. It is used to generate process plan automatically and hence to schedule manufacturing activities. The advantages of feature based design over conventional CAD approaches are the following.
1. It provides the ability to capture design intent and better understanding of the product geometry.
2. A means for designers to abstract the level of design by working with high level shapes along with other parameters for downstream applications instead of geometric details alone.
3. It encourages towards standardization leading to improvement in manufacturability and product quality.
4. It provides an easy method for modelling the mechanical engineering components with information on the downstream applications.
(Proceedings of
the National Conference on Advanced Manufacturing & Robotics, S. N. Shome, p. 248-249)
3. Safety Stock (production planning)
Old answer (better)
Safety Stock
The safety stock is a randomly varying reserve stock kept to ensure the
stock availability during the replenishment time against random variations of demand
and/or replenishment times.
(Gudehuss, T., Kotzab, H., Comprehensive Logistics, 2000,
pg.295)
New Answer
22.2 Safety Stock
Safety stock is used to buffer exceptions on the demand side - e.g. an unpredicted increase of sales - and o the supply side. Examples for exceptions on the supply side are lower production output resp. production backlog due to scrap or machine failure and increased transportation times.
22.2 Safety Stock
Safety stock is used to buffer exceptions on the demand side - e.g. an unpredicted increase of sales - and o the supply side. Examples for exceptions on the supply side are lower production output resp. production backlog due to scrap or machine failure and increased transportation times.
(Supply chain management with
APO: structures, modelling approaches, and implementation
of myCAP, Jörg Thomas Dickersbach, p.416)
4. Carbon Black(material)
Old Answer
Carbon Black
This is a material of major significance to the rubber industry, so it is no surprise that most rubber products we see in the market place are black in color. We have moved a long way from collecting carbon from smokey oil flames, which produced a material called lampblack. The next historical step was to burn natural gas against iron channels, then scrape off the carbon to produce a highly reinforcing material called channel black. Both the use of this black in the rubber industry and its source of supply is currently limited and its cost is somewhat high. There are two common methods of producing carbon black today. Heating natural gas in a silica brick furnace to form hydrogen and carbon, produces a moderately reinforcing material called thermal black. Alternatively, if we incompletely burn heavy petroleum fractions, then furnace blacks are produced. These are the most important blacks in terms of quantity used and available types.
(Andrew Ciesielski, An Introduction to Rubber Technology, pg.37-38)
New (better)
2.8.2 Carbon Black
Carbon black production is a significant modern industry. Carbon blacks are formed by the incomplete combustion or cracking of hydrocarbon gases and vapors derived from petroleum sources (Taylor, 1997; Sebok and Taylor, 2001) and are classified as furnace blacks(<50 nm diameter), acetylene blacks (40-55 nm diameter) and thermal blacks (100-500 nm diameter). Manufacturers of carbon blacks produce at least 70 products designed for specific applications.
Donnet and Voet (1976) report major differences in surface areas of carbon blacks as determined by TEM (Stem) and by adsorption of nitrogen at 77 K (Sbet). Differences between the two surface area values are due to (a) the precence of microporosity with the carbon black particle and (b) to capillary condensation of the nitrogen adsorbate (77 K) occuring between the carbon black particles which are close packed. On the other hand, for Spheron 6, values of Stem and Sbet both equal to 106 (m^2)/g, making this carbon black (and its graphitized product Graphon) suitable for adsorption studies of carbon surfaces.
(Activated carbon, Harry Marsh, p. 47)
5. Sandwich Molding (manufacturing method)
Old Answer (better)
Sandwich Molding
Sandwich molding involves injection of two separate polymers - one is the outer skin of the part and the other is the inner core, which is typically a polymer foam. A specially designed nozzle controls the flow sequence of the two polymers in the mold. The sequence is designed so that the core polymer is completely surrounded by the skin material inside the mold cavity. The final structure is similar to that of a structural foam molding. However, the molding possesses a smooth surface thus overcoming one of the major shortcomings of the previous process. In addition, it consists of two distinct plastics, each with its own characteristics suited to the application.
(Groover, M.P., Fundamentals of Modern Manufacturing: Materials, Processes, and Systems, 4th Edition, p.294)
New
9.1 Coinjection (Sandwich) Molding
Coinjection molding (sometimes called "sandwich molding") comprises sequential and/or concurrent injection of a "skin" material and a dissimilar but compatible "core" material into a cavity. This process produces parts that have a sandwich structure, with the core material embedded between the layers of the skin material. This innovative projess offers the inherent flexibility of using the optimal properties of each material to reduce the material cost, injection pressure, clamping tonnage, and residual stress to modify the property of the molded part, and/or to achieve particular engineering effects.
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