Kinematic Self-Replicating Machines
© 2004 Robert A. Freitas Jr. and Ralph C. Merkle. All Rights Reserved.
Robert A. Freitas Jr., Ralph C. Merkle, Kinematic Self-Replicating Machines, Landes Bioscience, Georgetown, TX, 2004.
3.16 The Collins Patents on Reproductive Mechanics (1997-1998)
The natural human urge towards material acquisitiveness has seemingly aspired to its most audacious and complete expression in two patent filings by Charles Michael Collins. Collins is an ambitious inventor who appears, in two patents actually granted by the U.S. Patent Office in 1997 [650] and 1998 [651], to have laid claim to the entire design space of artificial kinematic self-replicating machines – or, more specifically, to “the newly named field of science” called “Reproductive Mechanics.” The breathtaking scope of the Collins patents is illustrated by the following brief excerpts from the patent filing documents which are of public record.
In his first description of the invention, Collins [650] writes: “The present invention relates to a self-reproducing fundamental fabrication machine (F-Units), such as a high resolution fundamental fabricating unit system or machine having memory and processors for searching, identifying, acquiring, and accessing unlimited types of materials to be used in subsequent manufacturing; and, as well, for making products, other machines including machines of the same type, and ultimately, a fabricating machine that may replicate or reproduce itself as a new machine of the same order. The unlimited materials referred to include materials such as materials provided for acquisition and three dimension processor control with error correction and indices to facilitate the above fabricating and replicating functions in any media. The ultimate fabricating system of the invention in replicating or reproducing itself as a new machine, is an entity of components made capable by the present disclosure of fulfilling these stated objectives within usual and conventional and standard scientific precepts and engineering precepts and yet provides a self-correcting and perfecting feature not found in the prior art.” Figure 3.54 shows a schematic view of the basic Collins fabricator, taken from the first patent. While the patents appear not to present a specific workable design for any part of a practical self-replicating system, they may yet provide some inspiration to future engineers [1130].
Collins [650] expands further: “It is an object of the present invention to provide a machine system that may consist of components having a programmably determined structure defining the arrangement of the components, the system capably reproducing itself according to the programmably determined structure and consisting of fundamental fabricating means for diversely selecting and assembling its components consisting of diverse materials which are at least materials that severally are selected from a group of materials that consist essentially of materials that are electrically insulative, electrically conductive, and substances that are magnetically attractive.” Since all materials may be considered as either insulators or conductors, this claim would seem to encompass all known physical building materials.
In the second patent [651], the claims are further extended to include “a fabrication system for fabricating an object from a plurality of pieces which comprises:
(a) a data structure, including related data, representative of the object to be fabricated,
(b) at least one first apparatus adapted for reading the data from said data structure,
(c) a set of instructions, which utilize the data read from said data structure,
(d) at least one second apparatus capable of executing said instructions, and
(e) at least one moveable fabrication tool responsive to said instructions, for retrieving said pieces, placing said pieces based on said data of said data structure to form said object and processing said pieces in accordance with said data.”
The uses for the patented device would include, among a lengthy list of other things, “quick computer programmable assembly of most any simple object, simultaneous part creation and assembly of small machines, robot creation and upkeep, [and] purifying and perfecting work objects including the environment.”
These expansive claims are broadened still further in the second patent [651], seemingly to encompass the whole of kinematic artificial life: “It is a further object of this invention to provide: a fundamental fabricating machine system...which includes means for locating, purifying, perfecting, acquiring, metabolizing and assimilating sustenance in the environment with less symbiotic necessity than most natural present life forms, and, by way of a new means similar to robotics that is hereinafter newly named and claimed and coined herein as the newly named field of science ‘Reproductive Mechanics’ execute unitized reproduction of itself with no help from man after man has first created it and its systems and accessories, executing reproduction of its own needed living environment making it more cause than effect, having intellectual direction and purpose and acting in the direction of its own propagation and man’s and other life forms, adapting to the environment around it, being sensory and communicating with itself and/or man and/or computers, having reproducible and updateable memory with chaining capability and repeatable series and parallel operations with qualifications, and having a potentially infinite group life-span for providing thereby a man-made, evolutionary artificial life.”
Collins’ patented device “is by design an entity that endeavors to solve all man’s problems, physical and intellectual, with the shortest paths to these ends built in interactively as an intrinsic characteristic....As it further evolves within these aforestated primary directives the only thing left to be done (which it can do) is go about evolutionary improvements in the quality and quantity of its appointed tasks. Physical and intellectual self-reproductivity with improvement is the important feature that brings about this important aforestated state of affairs. Evolutionary programming which in this medium alters full change of shape and size in all parameters will eventually reduce the paths, between the intellect and the physical task, to a virtually negligible minimum so it (the F-Unit 10 and system) will be ultimately all that is necessary as virtually all man’s tasks will be efficiently handled for all within the physical plane; with the only exceptions being tasks done over large (planetary) distances.”
As a final legal catch-all in the unlikely event that some tiny corner of the kinematic replicator design space has been inadvertently omitted, the second patent [651] warns: “The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described except where specifically claimed, and accordingly, all suitable modifications and equivalents may be resorted to as falling within the scope of the claims.”
Replicating systems engineers who, upon reading the above, might become concerned that their existing or future inventions could infringe the Collins patents, should take note that the disclosures of prior art attested in both patent filings [650, 651] include not a single reference to von Neumann’s substantially identical prior work (beginning in 1948; Section 2.1.2). Astonishingly, von Neumann’s name appears nowhere in any of Collins’ documents, nor is there a single mention of any of the many hundreds of items of previously published relevant literature that are cited elsewhere in this book. These fatal omissions should have significant implications for the future viability and enforceability of the Collins patents.
In the field of kinematic self-replicating machines, the most directly relevant U.S. patents seem to include (with quoted abstracts) the following:
* U.S. 4,734,856 “Autogeneric system” (March 1988) [1131]: The invention of the “autogeneric system” is a closed recursive manufacturing cycle. The working model operates by the relentless application of directed trial and error. The copyrighted version can be used to manufacture microcomputer systems, and process control systems. The value of “autogeneric systems” rests in the inherent ability to create or manufacture complex systems on demand. The autogeneric system has been doubling in size and complexity about every three months while in use. One practical development has been the “Silicon Scribe,” a device that manufactures single chip computers from high level specifications. The autogeneric system has been used to bootstrap from a crude interpreter that operated on virtual machine instructions to the “archive,” a self replicating computer manufacturing system.
* U.S. 5,659,477 “Self reproducing fundamental fabricating machines (F-Units)” (August 1997) [650]: First Collins patent; see above.
* U.S. 5,764,518 “Self Reproducing Fundamental Fabricating Machine System” (June 1998) [651]: Second Collins patent; see above.
* U.S. 6,510,359 “Method and system for self-replicating manufacturing stations” (January 2003) [273]: A system and method which provide a non-biological self replicating manufacturing system (“SRMS”) are disclosed. A preferred embodiment provides an SRMS that enables assembly stations to replicate. In a preferred embodiment, positional assembly is utilized by one or more assembly stations to construct like assembly stations. Furthermore, in a most preferred embodiment, such assembly stations are small scale devices that are capable of working with small scale parts, such as micron-scale, nanometer-scale or even molecular-scale parts, in order to construct like assembly devices. The SRMS of a preferred embodiment performs surface-to-surface assembly. For example, an assembly station on a first surface (e.g., wafer), Surface A, constructs a like assembly station on another surface (e.g., wafer), Surface B. Most preferably, the assembly stations replicate at an exponential rate. (The Zyvex RotapodTM approach to “exponential assembly”; Section 4.17).
* U.S. 6,521,427 “Method for the complete chemical synthesis and assembly of genes and genomes” (February 2003) [1132]: The present invention relates generally to the fields of oligonucleotide synthesis. More particularly, it concerns the assembly of genes and genomes of completely synthetic artificial organisms. Thus, the present invention outlines a novel approach to utilizing the results of genomic sequence information by computer directed gene synthesis based on computing on the human genome database. Specifically, the present invention contemplates and describes the chemical synthesis and resynthesis of genes defined by the genome sequence in a host vector and transfer and expression of these sequences into suitable hosts. (The Egea biorobotics approach; Section 4.4).
Other possibly relevant or interesting U.S. patents include:
* U.S. 4,575,330 “Apparatus for production of three-dimensional objects by stereolithography” (March 1986) [1197]: A system for generating three-dimensional objects by creating a cross-sectional pattern of the object to be formed at a selected surface of a fluid medium capable of altering its physical state in response to appropriate synergistic stimulation by impinging radiation, particle bombardment or chemical reaction, successive adjacent laminae, representing corresponding successive adjacent cross-sections of the object, being automatically formed and integrated together to provide a step-wise laminar buildup of the desired object, whereby a three-dimensional object is formed and drawn from a substantially planar surface of the fluid medium during the forming process. (See Section 3.20.)
* U.S. 4,608,525 “Cellular type robot apparatus” (August 1986) [1133]: This invention relates to a cellular type robot apparatus consisting of a plurality of robot cells each having intelligence, wherein each robot cell controls its own operation on the basis of information exchange with adjacent robot cells. The operations of the robot cells are as a whole coordinated, and each robot cell can be controlled without the necessity of change of hard- and soft-wares even when one or more of the robot cells are out of order or when the robot needs to be expanded. Each robot cell can be provided so that the robot can be increased or decreased in a building block arrangement. More definitely, each robot cell has arms corresponding to hands and feet, and is able to control its own operation. As the robot cells are connected and combined through transmission routes so as to be able to exchange information, they can operate cooperatively as a group to perform a manipulative action. The operation of the group of robot cells is designed also to constitute the shape of a predetermined pattern besides the operations of entwining an object, and gripping and moving the object. (See Section 3.8.)
* U.S. 4,835,450 “Method and system for controlling robot for constructing products” (May 1989) [1134]: A 3-dimensional form of a sample product constituted by a plurality of parts having known forms is measured by imaging the sample product from a plurality of directions. Arrangement data representing the 3-dimensional positions and orientations of the parts constituting the sample product are obtained, by a construction detecting module, on the basis of the measured 3-dimensional form of the sample product. A task planning module sets a task for moving a part to be used for constructing a product and the sequence of the task by using arrangement data acquired by the construction detecting module. Upon generation of motion command data for controlling a robot for constructing the product in accordance with the task set by the task planning module, the generated motion command is output to a motion control module. The construction robot is controlled by the motion control module, whereby a product the same as the sample product is constructed.
* U.S. 4,964,062 “Robotic arm systems” (October 1990) [1135]: A multisection flexible multidigit arm contains hands at each end, each of which hands contains a set of fingers, suitably three, which are similarly formed flexible multidigit arms constructed to a smaller scale. Each hand contains connectors for coupling the hand to a mating connector mounted on an associated structure to provide appropriate power and control signals to the arm. One hand may grip the connector and the other hand is free to move to various positions and perform various tasks. In an additional aspect the arm may move to different locations by somersaulting between spaced connectors in the system. In an assembly system the robotic arms are used to construct frames or other assemblies. A completely self contained arm includes a self contained source of power. Radio communication means are provided to allow electronic interaction with the arm from a remote location. In an additional aspect the self contained circuitry includes processor means programmed to control the arm to perform a certain task, relieving the operator at the remote location from specifying the details. Control signals to the sections of the arm in an additional aspect to the disclosed invention are provided by an electrical system that uses only a few wires by multiplexing the signals and the actuators, effectively “time sharing” the electrical leads between the large number of actuators.
* U.S. 5,150,288 “Production management system and method of transmitting data” (September 1992) [1136]: A production management system for controlling a production line such as an automobile assembling line includes a plurality of slave computers for controlling assembling robots in assembling stations, and a host computer for supervising common information required by the slave computers. When the common information is to be modified due to a change in the robots, the common information stored in the host computer is modified into corrected common information, and the corrected common information is transmitted from the host computer to the slave computers. The common information stored in the slave computers can therefore be modified by the corrected common information.
* U.S. 5,210,821 “Control for a group of robots” (May 1993) [1137]: A control for robots wherein a plurality of control units are connected in a hierarchical structure including a plurality of ranks including the lowest rank, and the robots subordinate to the control units belonging to the lowest rank. The present invention relates to a control for a group of robots, each having a plurality of mobile axis drive mechanisms, which are assigned to perform a variety of functions to assemble a product, and more particularly to a control arrangement which makes it easy to locate malfunctions developing in the robots.
* U.S. 5,214,588 “Control apparatus for an FMS line” (May 1993) [1138]: A control apparatus provided for an FMS (flexible manufacturing system) line having a robot for carrying a workpiece and an AGV (automatically guided vehicle) for carrying a jig to be coupled to the workpiece. The control apparatus generally includes a production instruction device and an AGV movement control device. The production instruction device determines a schedule for supplying jigs on the basis of a work supply order schedule. The AGV movement control device causes an AGV to skip an unavailable station and to move to an available station in accordance with the presence or absence of a workpiece and/or a jig and a kind of a cell to which the AGV is to be moved. The robot operates continuously in the order of the disposition of cells.
* U.S. 5,283,943 “Automated assembly apparatus” (February 1994) [1139]: A method and apparatus for assembling multiple component products using automated assembly equipment having predetermined locations for loading of components or component compartments. The invention includes a component identifier which reads indicia of component identity from components or component compartments, and a location indicator which indicates a proper location for loading and identified component or component compartment. The invention also contemplates a sensor that senses the placement of components or component compartments in the locations of the assembly machine, and a disabling device which disables the assembly machine if components or component compartments are misplaced.
* U.S. 5,355,577 “Method and apparatus for the assembly of microfabricated devices” (October 1994) [1338]: A method of rapidly assembling many discrete microelectronic or micro-mechanical devices in a precise configuration. The devices are placed randomly on a template consisting of a pair of oppositely charged planar electrodes. The upper electrode contains a multiplicity of apertures. The template is vibrated and the devices are attracted to the apertures and trapped thereat. The shape of a given aperture determines the number, orientation, and type of device that it traps. The process is completed by mechanically and electrically connecting the devices. The present method for self-assembly allows many sub-millimeter sized electronic components or other particles to be rapidly assembled into a predetermined configuration.
* U.S. 5,390,283 “Method for optimizing the configuration of a pick and place machine” (February 1995) [1140]: A genetic algorithm is used to search for optimal configurations of a computer controlled pick and place machine, which places parts on printed circuit boards. Configurations include: assigning grippers to pipettes of the machine; assigning parts, destined for the printed circuit boards, to feeders of the machine; assigning parts to pipettes; and determining time intervals and orders in which parts are to be placed. The genetic algorithm is applied to chromosome strings representing parameters for determining machine configuration. A heuristic layout generator generates machine configurations from the chromosome strings.
* U.S. 5,390,282 “Process for problem solving using spontaneously emergent self-replicating and self-improving entities” (February 1995) [373]: An apparatus and process for solving problems using self-replicating and self-improving entities. The present invention includes an apparatus and process for solving a problem using a population of entities, wherein each of the entities is an arrangement of actions and material which are capable of including an incorporation action and are capable of including an emission action. (See Section 2.2.1.)
* U.K. GB19940004227, U.S. 6,157,872, “Programmable materials” (U.K. September 1995, U.S. December 2000) [816]: Programmable material is a collection of substantially cubic shaped bricks called monomers that move relative to each other under computer control to sculpt engineering structures and mechanisms (walking machine). The monomers have features to lock to other monomers and slide relative to other monomers without separating. The monomers are fault tolerant against damage; functional monomers move faulty monomers and replace them with functioning clones. Movement of monomers is broken down systematically into streamers, gateways, highways and reservoir methods to obtain individual monomer movement paths required to synthesize a structure. Specialized monomers can carry tools which together with synthesis of custom structures create custom machines. (Joseph Michael’s “fractal robots”; Section 3.8.)
* U.S. 5,468,851 “Construction of geometrical objects from polynucleotides” (November 1995) [1141]: One, two and three dimensional structures may be synthesized or modified from polynucleotides. A core structure is expanded by cleavage of a loop with a restriction endonuclease and ligating another polynucleotide to the sticky ends so that the recognition site of the restriction enzyme is not reformed. This process is repeated as many times as necessary to synthesize any desired structure. The structures formed have a wide range of uses. (Seeman’s DNA-based structures; Section 4.5.)
* U.S. 5,475,797 “Menu driven system for controlling automated assembly of palletized elements” (December 1995) [1142]: The present invention is a method and apparatus for defining the critical characteristics of a pallet, or tray, used to supply workpieces to an automated, flexible assembly station or workcell. Once the characteristics are described and stored in memory, they may be used to uniquely identify workpieces which are determined to be defective during the automatic assembly operations.
* U.S. 5,508,636 “Electronic system organized as an array of cells” (April 1996) [1143]: The invention concerns a programmable integrated electronic system including an array of identical cells. Each cell includes functional components capable, when they are correctly connected, of executing a given function, and programmable connecting means for on the one hand connecting the functional components to each other and on the other hand connecting the cell to its neighbors. The present invention is characterized in that the system includes means of storing a first data item which defines the function of each of the cells in the array and in that each cell has means for extracting, from this first data item and its location the network, the programming word for its own function. In addition, means are provided for effecting the test of correct functioning of each cell and for reconfiguring the array where there are defective cells.
* U.S. 5,539,975 “Control system and equipment configuration for a modular product assembly platform” (July 1996) [1144]: A modular product assembly platform which includes a multiple number of industrial robots or other similar assembly devices. The product assembly platform also includes a programmable controller system housed in a logic control cabinet, a vision control system housed in a vision control cabinet and a set of robot controllers which operate together to control the robots or assembly devices for performing product assembly tasks.
* U.S. 5,586,387 “Automated part assembly machine” (December 1996) [1145]: An automated part assembly machine has a work table supported to a base and movable relative thereto and at least two separate robots each having an end effector movable around within an individual work region. The two robots are positioned in such a relation as to give a common work region in which the individual work regions of the two robots overlap. A parts supply is arranged to the work table for storing parts to be picked up by the robots. A plurality of operator hands are selectively and removably attached to the end effector of the robot for handling the parts by the robot. Disposed within the common region is a jig which positions the parts for assembly by the robot. The robots and the work table are controlled to operate in cooperation for assembly of the parts. The robots are enabled to move together with the jig and the operator hands relative to the parts supply so that the robots can reach over a wide range of the parts supply beyond the individual work regions to thereby successfully pick up suitable parts and transfer them to the jig for immediate assembly of the parts. Further, since the operator hands are on the movable work table, the robot can change the operator hands while moving relative to the parts supply for effecting the part assembly substantially without interruption, in addition to the advantage of enabling one robot to change the operator hand while the other robot is handling the parts.
* U.S. 5,717,598 “Automatic manufacturability evaluation method and system” (February 1998) [1146]: A designed object workability evaluating system for evaluating quantitatively at a stage of designing an article whether a structure of the article as designed can be realized easily in a manufacturing stage for thereby selectively determining a best structure from a plurality of design plans through comparative evaluation thereof. A server machine section includes a registering unit storing evaluation elements defined by the user, an index calculating module for calculating indexes indicating degrees of difficulty/ease of work, an evaluation element estimating module, a part workability evaluation module, an article workability evaluation module, and a best design plan selection/determination module.
* U.S. 5,835,477 “Mass-storage applications of local probe arrays” (November 1998) [1147]: The present invention concerns a storage device comprising a local probe array and a storage medium with an array of storage fields (pits on surface). The local probe array is situated opposite to the storage medium such that each local probes of the local probe array can be scanned over the corresponding storage field. (The scanning-probe array or Millipede concept; Section 5.7.)
* U.S. 5,980,084 “Method and apparatus for automated assembly” (November 1999) [1148]: This invention relates to the field of assembly of mechanical systems, specifically automated planning of a sequence of steps for assembly or disassembly of a mechanical system comprising a plurality of parts. A process and apparatus generates a sequence of steps for assembly or disassembly of a mechanical system. Each step in the sequence is geometrically feasible, i.e., the part motions required are physically possible. Each step in the sequence is also constraint feasible, i.e., the step satisfies user-definable constraints. Constraints allow process and other such limitations, not usually represented in models of the completed mechanical system, to affect the sequence.
* U.S. 5,988,845 “Universal unit for automatically configuring three-dimensional structures of a desired shape” (November 1999) [1149]: A three-dimensional universal unit includes multiple identically configured assembly units, each having a central unit body, arms that can rotate relative to the unit body, the arms extending from the unit body in three orthogonal axes and having a connecting mechanism at the end of each arm. The assembly unit also has an information processing unit for controlling a motor in the unit body, an assembly unit operation, a rotary drive transmission system for transmitting arm drive motion from the motor, and a drive transmission system for engaging and disengaging the connecting mechanisms. Each connecting mechanism can mechanically connect with a connecting mechanism of another assembly unit and includes a communication device for exchanging information between information processing units of connected assembly units. (Another KCA system; Section 3.8.)
* U.S. 5,994,159 “Self-assembling micro-mechanical device” (November 1999) [2447]: A self-assembling micron-sized mechanical device is described. The device comprises hinged plates attached to a support. A beam having a first end free to move in an upwardly-directed arc is associated with each hinged plate comprising the device. The beam has a first engagement member, including a first angled edge, disposed at its freely-movable first end. Each hinged plate includes a second engagement member, including a second angled edge. In the unassembled state, at least a portion of the first engagement member lies beneath the second engagement member on the support. Actuation force is applied to the beam by an actuator, the force causing the first end of the beam to lift. As it does so, the first and second angled edges slide over another, and the hinged plate is rotated upwardly about its hinges away from the support. The mechanical advantage provided by the angled edges allows a hinged plate to be rotated fully ninety degrees away from the support. (Another example of “micro-origami” (Section 4.1.5), as is the work by Hui et al [1150].) Kris Pister first demonstrated silicon hinged plates in 1992 [2445] but the University of California at Berkeley did not pursue a patent.
* U.S. 6,072,044 “Nanoconstructions of geometrical objects and lattices from antiparallel nucleic acid double crossover molecules” (June 2000) [1151]: Two- and three-dimensional polynucleic acid structures, such as periodic lattices, may be constructed from an ordered array of antiparallel double crossover molecules assembled from single stranded oligonucleotides or polynucleotides. These antiparallel double crossover molecules have the structural rigidity necessary to serve as building block components for two- and three-dimensional structures having the high translational symmetry associated with crystals. (Seeman’s DNA-based structures; Section 4.5.)
* U.S. 6,142,358 “Wafer-to-wafer transfer of microstructures using break-away tethers” (November 2000) [1152]: Break-away tethers to secure electronic, mechanical, optical, or other microstructures, during release from one substrate and transfer to another. Microstructures are fabricated with integrated tethers attaching them to a first substrate. The structures are undercut by etching and contacted and bonded to a second substrate. First and second substrates are separated, breaking the tethers. (Relevant to MEMS positional assembly; see Section 4.17.)
* U.S. 6,200,782 “Construction of nucleoprotein
based assemblies comprising addressable components for nanoscale assembly and
nanoprocessors” (March 2001) [1153]:
A logical next step in biotechnology is the fabrication of assemblies and devices
on the nanometer scale. Since most devices take advantage of the proximity and
precise 3-D arrangement of individual components, one of the limitations in
the fabrication of nanoscale devices has been the inherent lack of specificity
in chemical methods for addressing components like bioengineered proteins to
precise locations in a 2-D array or 3-D lattice. Herein, a nucleoprotein based
nanoprocessor is described. The nanoprocessor includes one or more chimeric
fusion proteins linked to a DNA scaffold. Both components of the fusion protein
are enzymes. (See Section 4.5.)
* U.S. 6,205,362 “Constructing applications in distributed
control systems using components having built-in behaviors” (March 2001)
[1154]: A distributed control system including
self-organizing components which are preselected on the basis of built-in behaviors
which are needed to perform a particular application. The built-in behaviors
enable the components to automatically self-organize and perform the application
once coupled to the network.
* U.S. 6,233,502 “Fault tolerant connection system for transiently connectable modular elements” (May 2001) [1155]: A system and method for transiently connecting modular elements of a self-movable robot. The self-movable robot is known as metamorphosing robots, polymorphic robots, shape-changing robots, or morphable structures. The modular elements can act together to build a structure to perform a given task. Each robotic module contains a mechanism allowing for communication and transfer of power between adjacent modules, and defining a robot whole to be all the modules in one connected component. (Another KCA system; Section 3.8.)
* U.S. 6,535,786 “Modular automated assembly system” (March 2003) [1156]: A method of modular manufacturing is disclosed and a modular assembly system is shown utilizing a base unit and a plurality of detachable work stations adapted to operate with the base unit. Each detachable work station includes its own work station control processor. The assembly system is preferably fully modular since each work station is capable of controlling its own operation. Work stations may be plugged into a plurality of different work station ports on the base unit in a plurality of different combinations, preferably without reprogramming either the base unit control processor or the work station’s control processor.
Last updated on 1 August 2005