Multi-axis machine tool

Abstract

SOLUTION: One embodiment can be characterized as a method for controlling a multi-axis machine tool that includes: obtaining a preliminary rotary actuator command; based at least in part on the preliminary rotary actuator command, generating a processed rotary actuator command having frequency component within a bandwidth of the rotary actuator; and generating a first linear actuator command and a second linear actuator command based at least in part on the processed rotary actuator command.EFFECT: The processed rotary actuator command can be output to the rotary actuator. The first linear actuator command can be output to a first linear actuator, and the second linear actuator command can be output to a second linear actuator.SELECTED DRAWING: Figure 1

Description

Cross-reference to Related Applications

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 183,009, filed on Jun. 22, 2015, and U.S. Provisional Patent Application No. 62 / 281,967, filed on Jan. 22, 2016, the entire contents of which are incorporated herein by reference.

Technical Field

[0002] Embodiments of the present invention generally relate to systems and methods for enabling automatic motion control in which the position and movement of a tool within a multi-axis machine tool are controlled using one or more actuators. Background

[0003] Motion control is an important aspect in robotic systems, numerical control (NC) machines, computer numerical control (CNC) machines, etc. (collectively referred to herein as "machine tools" for the sake of generality and comprehensiveness, which can be adapted to process workpieces), which may involve (for example, multi-joint coordinate robot configurations, Cartesian coordinate robot configurations, cylindrical coordinate robot configurations, polar coordinate robot configurations, delta coordinate robot configurations, etc., or combinations thereof). These machine tools typically include one or more controllers, one or more actuators, one or more sensors (all of which can be single devices or built into the actuators), a tool holder or tool head, various data communication subsystems, an operator interface, and the like. Depending on the type and number of actuators included, the machine tool can be provided as a "multi-axis" machine tool having a plurality of independently controllable motion axes.

[0004] Due to the continued market demand for increasing productivity in machining applications and other automation applications, machine tools are increasingly being used with various types of actuators, sensors, and related controllers. In some cases, a multi-axis machine tool (also referred to herein as a "hybrid multi-axis machine tool") may include a plurality of actuators that can be moved along the same direction but with different bandwidths. Generally, an actuator (e.g., a first actuator) can be characterized as having a higher bandwidth than another actuator (e.g., a second actuator) if the first actuator can move more precisely in response to a command signal having a predetermined spectral component or frequency component than the second actuator can in response to the same command signal. However, the range of motion that the first actuator can move is often smaller than the range of motion that the second actuator can move.

[0005] Determining which motion elements to assign between a relatively high-bandwidth actuator and a relatively low-bandwidth actuator of a hybrid multi-axis machine tool is not an easy task. A common strategy is to operate one or more relatively low-bandwidth actuators to move the workpiece being processed, and further / or move one or more relatively high-bandwidth actuators to a desired position or "zone" where the workpiece is to be processed, and then maintain the position of the relatively low-bandwidth actuator constant while operating the relatively high-bandwidth actuator during the processing of the workpiece. Then, operate the relatively low-bandwidth actuator to move the workpiece and / or the relatively high-bandwidth actuator to another "zone" where the workpiece is processed. This "zone-by-zone" approach to motion control (also referred to as a "step and repeat" approach) is not desirable because it greatly limits the throughput and flexibility of the hybrid multi-axis machine tool. Also, it may be difficult to appropriately or advantageously define the various "zones" of the workpiece where the relatively high-bandwidth actuator can operate.

[0006] U.S. Patent No. 8,392,002 addresses the above problems related to implementing a "zone by zone" approach by processing a part description program and decomposing a (frequency-based) tool tip trajectory defined in the part description program into different sets of appropriate position control data for a relatively low bandwidth actuator and a relatively high bandwidth actuator of a hybrid multi-axis machine tool. The content of this U.S. Patent is hereby incorporated by reference in its entirety. However, as recognized in U.S. Patent No. 8,392,002, when a hybrid multi-axis machine tool is configured to hold a workpiece using a 5-axis CNC manipulator with two rotational axes on a 3-axis orthogonal coordinate stage and includes a relatively high bandwidth actuator for moving the tool tip in three orthogonal coordinate axes, an error in the angle associated with the rotational axis can occur when using a frequency-based decomposition approach. Summary

[0007] One embodiment of the present invention can be characterized as a method for controlling a multi-axis machine tool configured to machine a workpiece using a tool. The multi-axis machine tool can include a rotary actuator configured to cause relative movement between the tool and the workpiece about a first axis, a first linear actuator configured to cause relative movement between the tool and the workpiece about the first axis, and a second linear actuator configured to cause relative movement between the tool and the workpiece about a second axis. The method can include obtaining a preliminary rotary actuator command (the rotary actuator command having a frequency component exceeding the bandwidth of the rotary actuator), generating a processed rotary actuator command having a frequency component within the bandwidth of the rotary actuator based at least in part on the preliminary rotary actuator command, and generating a first linear actuator command and a second linear actuator command based at least in part on the processed rotary actuator command. The processed rotary actuator command can be output to the rotary actuator, the first linear actuator command can be output to the first linear actuator, and the second linear actuator command can be output to the second linear actuator.

[0008] Other embodiments of the present invention can be characterized as a controller for controlling a multi-axis machine tool (exemplarily described above, for example). The controller may include at least one processor and a computer memory accessible to the at least one processor. Instructions are stored in the computer memory, and when executed by the at least one processor, the instructions cause the controller to generate a processed rotary actuator command (the processed rotary actuator command having a frequency component within the bandwidth of the rotary actuator) based at least in part on a preliminary rotary actuator command having a frequency component exceeding the bandwidth of the rotary actuator, generate a first linear actuator command and a second linear actuator command based at least in part on the processed rotary actuator command, and output the processed rotary actuator command, the first linear actuator command, and the second linear actuator command.

[0009] Other embodiments of the present invention include a tool configured to process a workpiece, a first rotary actuator configured to cause relative movement between the tool and the workpiece about a first axis, a first linear actuator configured to cause relative movement between the tool and the workpiece along the first axis, a second linear actuator configured to cause relative movement between the tool and the workpiece along a second axis, and a controller operably coupled to the rotary actuator, the first linear actuator, and the second linear actuator. The controller is configured to generate a processed rotary actuator command (the processed rotary actuator command having frequency components within the bandwidth of the rotary actuator) based at least in part on a preliminary rotary actuator command having frequency components exceeding the bandwidth of the rotary actuator, generate a first linear actuator command and a second linear actuator command based at least in part on the processed rotary actuator command, output the processed rotary actuator command to the rotary actuator, output the first linear actuator command to the first linear actuator, and output the second linear actuator command to the second linear actuator. BRIEF DESCRIPTION OF THE DRAWINGS

[0010]

Figure 1

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[0011] Hereinafter, examples of embodiments will be described with reference to the accompanying drawings. Unless otherwise explicitly stated, in the drawings, the sizes, positions, etc. of components, features, elements, etc. and the distances between them are not necessarily to scale and are exaggerated for ease of understanding.

[0012] The terms used in the specification are for the purpose of describing specific exemplary embodiments only and are not intended to be limiting. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form. Further, the terms "comprises" and / or "comprising," as used herein, specify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. Unless otherwise indicated, when a range of values is recited, the range includes not only the sub-ranges between the upper and lower limits of the range, but also the upper and lower limits themselves. Unless otherwise indicated, terms such as "first" and "second" are used only to distinguish elements from each other. For example, an actuator can be referred to as "the first actuator" and another node can be referred to as "the second actuator," or vice versa. The section headings used in this specification are for organization purposes only and should not be construed as limiting the subject matter described.

[0013] Unless otherwise indicated, terms such as "about" and "approximately" mean that the quantity, size, formulation, parameters, and other quantities and characteristics are not exact and need not be exact, and may be approximate, reflecting tolerances, conversion factors, rounding, measurement errors, etc., and other factors known to those skilled in the art, and may be larger or smaller as appropriate.

[0014] In this specification, spatially relative terms such as "downward", "below", "lower side", "upward", and "upper side" may be used to facilitate explanation when describing the relationship of one element or feature to another element or feature as shown in the figures. It should be understood that spatially relative terms are intended to include different directions in addition to the directions shown in the figures. For example, an element described as being "downward" or "below" another element or feature will face "upward" of the other element or feature when the object in the figure is inverted. Thus, the exemplary term "downward" can include both upward and downward directions. When the object faces other directions (e.g., when rotated 90 degrees or in other directions), the spatially relative descriptors used in this specification can be interpreted accordingly.

[0015] Like numerals throughout generally refer to like elements. For this reason, the same or similar numbers may be described with reference to other drawings even if not referred to or described in the corresponding drawings. Also, elements without reference numerals may be described with reference to other drawings.

[0016] Numerous different forms and embodiments are contemplated without departing from the spirit and teachings of the present disclosure, and the present disclosure should not be construed as limited to the exemplary embodiments described herein. Rather, these examples and embodiments are provided so that the present disclosure is complete and inclusive and conveys the scope of the present disclosure to those skilled in the art.

[0017] I. Summary Generally, embodiments described herein can be characterized as methods for controlling a multi-axis machine tool configured to machine a workpiece. Examples of multi-axis machine tools that can be controlled in accordance with embodiments described herein include milling machines, lathes, plasma machining systems, electrical discharge machining (EDM) systems, laser machining systems, laser marking devices, laser drilling devices, laser engraving devices, remote laser welding robots, 3D printers, water jet high-pressure jet cutters, abrasive jet cutters, and the like. Thus, it can be characterized as being configured to physically contact a mechanical structure such as a router bit, drill bit, tool bit, grinding bit, blade, etc. with a workpiece to remove, cut, polish, roughen, or the like, one or more materials constituting the workpiece. In addition to, or alternatively to, this, the multi-axis machine tool can direct energy (e.g., laser light generated by a laser source, heat generated by a torch, an ion beam or an electron beam generated from an ion source or an electron source, or any combination thereof), or direct a flow or jet of a substance (e.g., water, air, sand or other abrasive particles, paint, metal powder, or any combination thereof) to remove, cut, drill, polish, roughen, heat, melt, vaporize, ablate, crack, discolor, foam, or otherwise modify or change one or more properties or characteristics (e.g., chemical composition, crystal structure, electronic structure, microstructure, nanostructure, concentration, viscosity, refractive index, magnetic permeability, relative permittivity, etc.) of one or more materials constituting the workpiece. Such materials can be present on the outer surface of the workpiece before or during workpiece machining, or can be located inside the workpiece before or during workpiece machining (i.e., may not be present on the outer surface of the workpiece).

[0018] Regardless of how the workpiece is processed, the mechanism used to process the workpiece (for example, any of the mechanical structures described above, a directional energy, a flow or jet of a directional substance, or any combination thereof) is referred to herein as a "tool". One or more portions of the tool that physically contact the workpiece or one or more portions of the tool that interact with the workpiece (for example, through absorption of heat or electromagnetic radiation within the workpiece, or by converting the kinetic energy of electrons or ions incident within the workpiece into heat, or by workpiece corrosion, etc.) are each and collectively referred to herein as a "tool tip", and the region of the workpiece that is ultimately processed by the tool (for example, at the tool tip) is referred to herein as the "tooling region". In embodiments where the tool is a mechanical structure that is rotatable about an axis that intersects the workpiece (similar to, for example, a router bit, a drill bit, etc.), or in embodiments where the tool is a flow or jet of energy or substance that is directed towards the workpiece along an axis that intersects the workpiece, the angle of the axis with respect to the portion of the surface of the workpiece where the axes intersect is referred to herein as the "tooling angle".

[0019] A multi-axis machine tool includes one or more actuators that position a tool tip, or position a workpiece, or move the tool tip relative to the workpiece, or move the workpiece relative to the tool tip, or any combination thereof. Thus, when causing relative movement between the tool tip and the workpiece, the positioning of the machining area on or within the workpiece can be changed. Each actuator may be arranged or configured to position the machining area or cause relative movement between the machining area and the workpiece along at least one linear axis, or along at least one rotational axis, or any combination thereof. As is known in the art, examples of linear axes include the X-axis, the Y-axis (perpendicular to the X-axis), and the Z-axis (perpendicular to the X-axis and the Y-axis), and examples of rotational axes include the A-axis (i.e., defining rotation about an axis parallel to the X-axis), the B-axis (i.e., defining rotation about an axis parallel to the Y-axis), and the C-axis (i.e., defining rotation about an axis parallel to the Z-axis).

[0020] An actuator arranged or configured to position a tooling area along a linear axis or to cause relative movement between the tooling area and a workpiece is generally referred to as a "linear actuator". An actuator arranged or configured to position a tooling area along a rotational axis or to cause relative movement between the tooling area and a workpiece is generally referred to as a "rotary actuator". Examples of linear actuators that may be included within a multi-axis machine tool include one or more X-axis actuators (i.e., actuators arranged or configured to cause movement along the X-axis), one or more Y-axis actuators (i.e., actuators arranged or configured to cause movement along the Y-axis), one or more Z-axis actuators (i.e., actuators arranged or configured to cause movement along the Z-axis), or any combination thereof. Examples of rotary actuators that may be included within a multi-axis machine tool include one or more A-axis actuators (i.e., actuators arranged or configured to cause movement along the A-axis), one or more B-axis actuators (i.e., actuators arranged or configured to cause movement along the B-axis), one or more C-axis actuators (i.e., actuators arranged or configured to cause movement along the C-axis), or any combination thereof.

[0021] A multi-axis machine can be characterized as a "spectrum-complementary" multi-axis machine tool or as a "non-spectrum-complementary" multi-axis machine tool. A spectrum-complementary multi-axis machine tool includes one or more sets of redundant actuators that can cause movement along the same axis with different bandwidths. A non-spectrum-complementary multi-axis machine tool does not include a set of redundant actuators.

[0022] A multi-axis machine tool can be characterized as an "axis-direction complementary" multi-axis machine tool or a "non-axis-direction complementary" multi-axis machine tool. An axis-direction complementary multi-axis machine tool has a set of axis-direction complementary actuators including at least one rotary actuator configured to position a tool tip and / or a workpiece or cause movement relative to the tool tip and / or the workpiece along at least one rotational axis, and at least one linear actuator configured to position the tool tip and / or the workpiece or cause movement relative to the tool tip and / or the workpiece along at least one linear axis. In an axis-direction complementary multi-axis machine tool, at least one rotational axis about which a tool and / or a workpiece can rotate is not parallel to at least one linear axis along which the tool and / or the workpiece can translate. For example, a set of axis-direction complementary actuators can include a rotary actuator configured to cause movement along the B axis and at least one linear actuator configured to cause movement along the X axis, or the Z axis, or both the X axis and the Z axis. In another example, a set of axis-direction complementary actuators can include a rotary actuator configured to cause movement along the B axis, at least one rotary actuator configured to cause movement along the C axis, and at least one linear actuator configured to cause movement along the X axis, or the Z axis, or both the X axis and the Z axis. However, generally, a set of axis-direction complementary actuators can be characterized as being non-redundant with respect to each other. A non-axis-direction complementary multi-axis machine tool does not include a set of axis-direction complementary actuators. It should be understood that either a spectrum complementary multi-axis machine tool or a non-spectrum complementary multi-axis machine tool can be configured as an axis-direction complementary multi-axis machine tool or a non-axis-direction complementary multi-axis machine tool.

[0023] Generally, the actuators of a multi-axis machine tool are driven in response to actuator commands obtained or acquired from a computer file or a computer program. In embodiments where the actuator commands are obtained from a computer file or a computer program, such actuator commands may be interpolated from a locus (or a component of a locus) defined within the computer file or by the computer program. This locus may define a series of positions and / or movements (e.g., along one or more spatial axes) of the tool tip and / or the workpiece, which describe how to position, orient, and move the machining area by the multi-axis machine tool during the machining of the workpiece.

[0024] Generally, different actuator commands may correspond to different axial positions or movements. For this reason, a "linear actuator command" is an actuator command corresponding to a linear component of a position or a movement, and a "rotary actuator command" is an actuator command corresponding to a rotational component of a position or a movement. In particular, an "X-axis actuator command" may correspond to a linear component of a position or a movement along the X-axis, a "Y-axis actuator command" may correspond to a linear component of a position or a movement along the Y-axis (the Y-axis is orthogonal to the X-axis), and a "Z-axis actuator command" may correspond to a linear component of a position or a movement along the Z-axis (the Z-axis is orthogonal to the Y-axis). An "A-axis actuator command" may correspond to a rotational component of a position or a movement along the "A-axis" (the A-axis rotational movement represents the characteristics of a rotation centered on an axis parallel to the X-axis), a "B-axis actuator command" may correspond to a rotational component of a position or a movement along the "B-axis" (the B-axis rotational movement represents the characteristics of a rotation centered on an axis parallel to the Y-axis), and a "C-axis actuator command" may correspond to a rotational component of a position or a movement along the "C-axis" (the C-axis rotational movement represents the characteristics of a rotation centered on an axis parallel to the Z-axis).

[0025] As used herein, the term "actuator command" means an electrical signal characterized by an amplitude that varies over time, and thus may be characterized in the art by the expression "frequency component". Typically, the actuators of a multi-axis machine tool are characterized by one or more constraints (such as speed conditions, acceleration conditions, jerk conditions, etc.) that limit the bandwidth of the actuator. As used herein, the "bandwidth" of an actuator means the ability of the actuator to accurately and reliably respond or react to an actuator command (or a portion of an actuator command) having a frequency component that exceeds a threshold frequency associated with the actuator. It should be understood that the threshold frequency of any particular actuator can vary depending on the type of that particular actuator, the particular configuration of that particular actuator, the mass of that particular actuator, the mass of the object attached to or moved by that particular actuator, etc. For example, the threshold frequencies for actuators of types such as servo motors, stepper motors, hydraulic cylinders, etc. may be the same or different from each other (as known in the art), but generally, the threshold frequencies for actuators of types such as galvanometers, voice coil motors, piezoelectric actuators, electron beam magnetic deflectors, magnetostrictive actuators, etc. (which may be the same or different from each other as known in the art) are lower. Depending on how the actuator is configured, a rotary actuator may have a lower threshold frequency than a linear actuator.

[0026] Ultimately, the actuator commands are output to the corresponding actuators of the multi-axis machine tool. Each actuator can position or move the tool tip and / or the workpiece along the axis corresponding to the position or movement component associated with the received actuator command. For example, an X-axis actuator command is ultimately output to a linear actuator arranged or configured to position or move the tool tip and / or the workpiece along the X-axis, and a B-axis actuator command is ultimately output to a rotary actuator arranged or configured to position or move the tool tip and / or the workpiece along the B-axis (i.e., to rotate the tool tip and / or the workpiece about the Y-axis), and so on. When the trajectory describes a movement that can be decomposed into two or more movement components (e.g., a parallel movement in two or more of the X-axis, Y-axis, Z-axis, A-axis, B-axis, or C-axis), such movement components can be characterized as being "associated" with each other. Actuator commands corresponding to the associated components of the movement described by the trajectory can likewise be characterized as being "associated" with each other. When the actuator commands are output to the actuators synchronously or in cooperation, the actuators essentially react or respond by causing a relative movement between the tool tip and the workpiece so as to move the tooling area along a path that matches or corresponds to the desired trajectory.

[0027] Some general embodiments regarding the generation and use of several sets of actuator commands (i.e., "spectrum complementary actuator commands" and "axial complementary actuator commands") are described in the following section. Although it is generally described that two sets of actuator commands are generated and used separately, it should be understood that the two sets of actuator commands can be generated and used together in combination. In connection with FIGS. 1 to 4, examples of generating and using two sets of actuator commands in combination are described in detail.

[0028] A. Embodiments generally related to actuator commands for a spectrally complementary multi-axis machine tool In an embodiment where the multi-axis machine tool is a hybrid multi-axis machine tool, a set of spectrally complementary actuator commands can be output to a corresponding set of redundant actuators. In a set of spectrally complementary actuator commands, the frequency components of one of the actuator commands (e.g., the first actuator command) are higher than the frequency components of the other actuator commands (e.g., the second actuator command) among the actuator commands, and the first actuator command is ultimately output to the actuator with a relatively high bandwidth within the set of redundant actuators that can accurately or surely respond or react (e.g., can accurately or surely respond to the first spectrally complementary actuator command), and the second actuator command is ultimately output to the actuator with a relatively low bandwidth in the set of redundant actuators that can respond or react more accurately or more surely (e.g., can respond or react more accurately to the second frequency command than to the first frequency command).

[0029] The set of spectrally complementary actuator commands can be generated by any suitable method. For example, the set of spectrally complementary actuator commands can be obtained from or acquired from a computer file or computer program as described above, or can be generated by processing actuator commands (e.g., those describing a position or movement along a single axis such as the X-axis, Y-axis, Z-axis, A-axis, B-axis, or C-axis). In this case, such actuator commands are also referred to as "preliminary actuator commands" and have frequency components over a preliminary frequency range. The preliminary frequency range can include non-negligible frequency components at one or more frequencies that exceed the threshold frequency of at least one of the actuators in the set of redundant actuators. This preliminary actuator command can be processed to generate a set of spectrally complementary actuator commands.

[0030] Generally, each spectral complementary actuator command has frequency components that span a frequency subrange within a preliminary range and narrower than the preliminary range. Specifically, the frequency components of each actuator command in a set of spectral complementary actuator commands include non-ignorable frequency components at one or more frequencies that do not exceed the threshold frequency of the corresponding actuator in the set of redundant actuators. For example, among a set of spectral complementary actuator commands, the frequency components of one of the spectral complementary actuator commands (e.g., the first spectral complementary actuator command that is finally output to the first actuator in the set of redundant actuators) span the first frequency subrange, and the frequency components of the other command among the spectral complementary actuator commands (e.g., the second spectral complementary actuator command that is finally output to the second actuator in the set of redundant actuators) span the second frequency subrange. In one embodiment, the average frequency of the first subrange may be lower than, higher than, or the same as the average frequency of the second subrange. The range of the first subrange may be larger than, smaller than, or the same as the range of the second subrange. The first subrange may overlap with, be adjacent to, or be separated from the second subrange.

[0031] In one embodiment, the processing of the preliminary actuator command may include modifying the preliminary actuator command (or other commands obtained from the preliminary actuator command) according to one or more suitable algorithms, or reducing the preliminary actuator command (or other commands obtained from the preliminary actuator command), or applying one or more suitable filters to the preliminary actuator command (or other commands obtained from the preliminary actuator command), or applying one or more low-order interpolations to the preliminary actuator command (or other commands obtained from the preliminary actuator command), or the like, or any combination thereof. Examples of suitable filters include digital filters, low-pass filters, Butterworth filters, etc., or any combination thereof. Examples of suitable algorithms include autoregressive moving average algorithms, etc. In one embodiment, a set of spectrally complementary actuator commands can be generated as described in one or more of U.S. Pat. Nos. 5,751,585, 6,706,999, and 8,392,002. Each of these U.S. patents is hereby incorporated by reference in its entirety. However, it should be understood that a set of spectrally complementary actuator commands can be generated by the methods described in one or more of U.S. Pat. Nos. 5,638,267, 5,988,411, 9,261,872, or in one or more of U.S. Patent Application Publication Nos. 2014 / 0330424, 2015 / 0158121, 2015 / 0241865. Each of these U.S. patents and U.S. Patent Application Publication Nos. is hereby incorporated by reference in its entirety.

[0032] The set of processed spectral complementary actuator commands is described as including only two spectral complementary actuator commands, but it should be understood that the set of spectral complementary actuator commands may include any number (e.g., 3, 4, 5, 6, 7, 8, etc.) of spectral complementary actuator commands. The number of spectral complementary actuator commands in a set of spectral complementary actuator commands corresponding to a common axis can be made equal to the number of redundant actuators in a set of redundant actuators that can perform positioning or movement along the common axis.

[0033] B. Embodiments generally related to actuator commands for an axially complementary multi-axis machine tool Sometimes, the rotary actuator command (e.g., B-axis actuator command) sent to a rotary actuator (e.g., B-axis actuator) includes a non-negligible frequency component that exceeds the threshold frequency of the rotary actuator. Therefore, in an embodiment where the multi-axis machine tool is an axis-direction complementary multi-axis machine tool, a set of axis-direction complementary actuator commands may be output to a set of axis-direction complementary actuators including a rotary actuator to compensate for the limited bandwidth performance of the rotary actuator. For example, a set of axis-direction complementary actuator commands may include an axis-direction complementary rotary actuator command having a frequency component that does not exceed the threshold frequency of the rotary actuator and at least one axis-direction complementary linear actuator command. The axis-direction complementary rotary actuator command may be output to the rotary actuator, and at least one axis-direction complementary linear actuator command may be output to one or more corresponding linear actuators (i.e., those within the same set of axis-direction complementary actuators as the rotary actuator).

[0034] A set of axial complementary actuator commands can be generated by any suitable method. For example, by processing a rotary actuator command (e.g., one that describes a position or movement along a single rotation axis such as the B-axis) obtained or acquired from a computer file or computer program as described above, a set of axial complementary actuator commands can be generated. In this case, such a rotary actuator command, also referred to as a "rotary actuator command," has frequency components over a preliminary frequency range. The preliminary frequency range can include frequency components that cannot be ignored at one or more frequencies above the threshold frequency of the rotary actuator. The preliminary rotary actuator command is processed to generate a set of axial complementary actuator commands that includes at least one axial complementary rotary actuator command and at least one axial complementary linear actuator command.

[0035] In certain embodiments, the processing of the preliminary rotary actuator command can include modifying the preliminary rotary actuator command (or other commands obtained from the preliminary rotary actuator command) according to one or more suitable algorithms, or reducing the preliminary rotary actuator command (or other commands obtained from the preliminary rotary actuator command), or applying one or more suitable filters to the preliminary rotary actuator command (or other commands obtained from the preliminary rotary actuator command), or applying one or more low-order interpolations to the preliminary rotary actuator command (or other commands obtained from the preliminary rotary actuator command), or the like, or any combination thereof. Examples of suitable filters can include digital filters, low-pass filters, Butterworth filters, etc., or any combination thereof. Examples of suitable algorithms can include autoregressive moving average algorithms, etc.

[0036] II. Control of a multi-axis machine tool having axially complementary actuators and redundant linear actuators FIG. 1 is a block diagram schematically showing a control system 100 for controlling a multi-axis machine tool. According to one embodiment, the multi-axis machine tool includes a relatively low-bandwidth X-axis actuator 102, a relatively low-bandwidth Y-axis actuator 104, a relatively low-bandwidth Z-axis actuator 106, a relatively high-bandwidth X-axis actuator 108, a relatively high-bandwidth Y-axis actuator 110, a relatively high-bandwidth Z-axis actuator 112, a B-axis actuator 114, and a C-axis actuator 116. A legend showing the spatial relationship between the axes described herein is indicated at 118.

[0037] The relatively low-bandwidth and relatively high-bandwidth X-axis actuators 102 and 108 respectively constitute a set of redundant actuators (i.e., a set of redundant X-axis actuators). Similarly, a set of redundant actuators is constituted by the sets of relatively low-bandwidth and relatively high-bandwidth Y-axis actuators 104 and 110 respectively (i.e., a set of redundant Y-axis actuators) and the sets of relatively low-bandwidth and relatively high-bandwidth Z-axis actuators 106 and 112 respectively (i.e., a set of redundant Z-axis actuators). The illustrated embodiment describes a multi-axis machine tool having a set of redundant linear actuators composed of only two linear actuators, but the multi-axis machine tool may further include one or more additional linear actuators arranged or configured to cause movement along any of the X-axis, Y-axis, and Z-axis, and it will be understood that any set of redundant actuators may include three or more linear actuators.

[0038] In one embodiment, none of the actuators in any pair of redundant actuators are attached to, or moved by, other actuators in the same pair of redundant actuators. For example, the relatively high bandwidth X-axis actuator 108 is not attached to, and is not moved by, the relatively low bandwidth X-axis actuator 102. However, in other embodiments, at least one actuator within a pair of redundant actuators may be attached to, or moved by, other actuators in the same pair of redundant actuators. In such embodiments, a relatively low bandwidth actuator in a pair of redundant actuators may move, or be moved by, a relatively high bandwidth actuator in the same pair of redundant actuators.

[0039] In one embodiment, considering one or more actuators in a pair of redundant X-axis actuators and / or one or more actuators in a pair of redundant Z-axis actuators, the B-axis actuator 114 constitutes a pair of axially complementary actuators. In other embodiments, considering one or more actuators in a pair of redundant X-axis actuators and / or one or more actuators in a pair of redundant Y-axis actuators, the C-axis actuator 116 constitutes a pair of axially complementary actuators. In yet other embodiments, considering one or more actuators in a pair of redundant X-axis actuators, one or more actuators in a pair of redundant Y-axis actuators, and / or one or more actuators in a pair of redundant Z-axis actuators, the B-axis actuator 114 and the C-axis actuator 116 constitute a pair of axially complementary actuators.

[0040] In the illustrated embodiment, the multi-axis machine tool does not include an A-axis actuator. However, it should be understood that the multi-axis machine tool may include an A-axis actuator, and the embodiments described herein may be adapted to control the A-axis actuator as described herein.

[0041] A. Embodiments related to a workpiece positioning assembly In one embodiment, a relatively low bandwidth X-axis actuator 102, a relatively low bandwidth Y-axis actuator 104, a relatively low bandwidth Z-axis actuator 106, a B-axis actuator 114, and a C-axis actuator 116 may be integrated as part of a "workpiece positioning assembly" configured to position or move a workpiece simultaneously or non-simultaneously along the X-axis, Y-axis, Z-axis, B-axis, C-axis, or any combination thereof. For example, each of the relatively low bandwidth X-axis actuator 102, relatively low bandwidth Y-axis actuator 104, relatively low bandwidth Z-axis actuator 106, B-axis actuator 114, and C-axis actuator 116 may include one or more elements (e.g., stages, fixtures, chucks, rails, bearings, brackets, clamps, straps, bolts, screws, pins, retaining rings, connecting members, etc. (not shown)) that enable one or more of these actuators to be attached to or mechanically coupled to each other. In this case, the relatively low bandwidth Z-axis actuator 106 may be placed on the relatively low bandwidth X-axis actuator 102 (e.g., such that it is movable by the relatively low bandwidth X-axis actuator 102), the relatively low bandwidth Y-axis actuator 104 may be placed on the relatively low bandwidth Z-axis actuator 106 (e.g., such that it is movable by the relatively low bandwidth Z-axis actuator 106, relatively low bandwidth X-axis actuator 102, or a combination thereof), the B-axis actuator 114 may be placed on the relatively low bandwidth Y-axis actuator 104 (e.g., such that it is movable by the relatively low bandwidth Y-axis actuator 104, relatively low bandwidth Z-axis actuator 106, relatively low bandwidth X-axis actuator 102, or any combination thereof), and the C-axis actuator 116 may be placed on the B-axis actuator 114 (e.g., such that it is movable by the B-axis actuator 114, relatively low bandwidth Y-axis actuator 104, relatively low bandwidth Z-axis actuator 106, relatively low bandwidth X-axis actuator 102, or any combination thereof).FIG. 2 schematically shows an exemplary configuration of an actuator in the workpiece positioning assembly (e.g., workpiece positioning assembly 200) described above. However, in other embodiments, one or more of the actuators within the workpiece positioning assembly may be arranged differently in any other suitable or desired manner. Also, it should be understood that one or more of the relatively low-bandwidth X-axis actuator 102, relatively low-bandwidth Y-axis actuator 104, relatively low-bandwidth Z-axis actuator 106, B-axis actuator 114, and C-axis actuator 116 may be omitted from the workpiece positioning assembly when appropriate or as needed.

[0042] From the above perspective, each of the relatively low-bandwidth X-axis actuator 102, relatively low-bandwidth Y-axis actuator 104, relatively low-bandwidth Z-axis actuator 106, B-axis actuator 114, and C-axis actuator 116 may be one or more stages (e.g., direct drive stage, lead screw stage, ball screw stage, belt drive stage, etc.) driven by one or more hydraulic cylinders, one or more pneumatic cylinders, one or more servo motors, one or more voice coil actuators, one or more piezoelectric actuators, one or more electrostrictive elements, etc., or any combination thereof. Further, any of the relatively low-bandwidth X-axis actuator 102, relatively low-bandwidth Y-axis actuator 104, relatively low-bandwidth Z-axis actuator 106, B-axis actuator 114, and C-axis actuator 116 may be configured to provide continuous motion or stepwise (incremental) motion.

[0043] A workpiece fixture (not shown) may be mechanically coupled to the workpiece positioning assembly (e.g., in a C-axis actuator 116 with a relatively low bandwidth) to hold, retain, transfer, etc. the workpiece in any suitable or desired manner. Thus, the fixture can connect the workpiece to the workpiece positioning assembly. The workpiece fixture may be one or more chucks or other clamps, clips, or other fixing devices (e.g., bolts, screws, retaining rings, straps, connecting members, etc.) that can clamp, fix, hold, adhere, or support the workpiece.

[0044] B. Embodiments related to a tool tip positioning assembly In one embodiment, a relatively high-bandwidth X-axis actuator 108, a relatively high-bandwidth Y-axis actuator 110, and a relatively high-bandwidth Z-axis actuator 112 may be incorporated within a "tool tip positioning assembly" configured to simultaneously or non-simultaneously position or move a tool tip associated with a multi-axis machine tool along the X-axis, Y-axis, Z-axis, or any combination thereof. However, it should be understood that the relatively high-bandwidth X-axis actuator 108, the relatively high-bandwidth Y-axis actuator 110, and the relatively high-bandwidth Z-axis actuator 112 may be omitted from the tool tip positioning assembly when appropriate or as necessary. Generally, depending on the mechanism (i.e., the "tool" used) for processing the workpiece, the tool tip positioning assembly can be characterized as a "serial tool tip positioning assembly", or a "parallel tool tip positioning assembly" or a "hybrid tool tip positioning assembly" (e.g., combining features specific to serial and parallel tool tip positioning assemblies).

[0045] i. Embodiments related to a serial tool tip positioning assembly In one embodiment, when the tool being used is a mechanical structure (e.g., router bit, drill bit, tool bit, grinding bit, blade, etc.), a serial tool tip positioning assembly can be used. Within the serial tool tip positioning assembly, each of the relatively high bandwidth X-axis actuator 108, relatively high bandwidth Y-axis actuator 110, and relatively high bandwidth Z-axis actuator 112 may include one or more elements (e.g., stages, fixtures, chucks, rails, bearings, brackets, clamps, straps, bolts, screws, pins, retaining rings, connecting members, etc. (not shown)) that enable one or more of such actuators to be attached to or mechanically coupled to each other. In this case, the relatively high bandwidth Y-axis actuator 110 may be mounted on the relatively high bandwidth X-axis actuator 108 (e.g., so as to be movable by the relatively high bandwidth X-axis actuator 108), and the relatively high bandwidth Z-axis actuator 112 may be mounted on the relatively high bandwidth Y-axis actuator 110 (e.g., so as to be movable by the relatively high bandwidth Y-axis actuator 110, the relatively high bandwidth X-axis actuator 108, or any combination thereof). However, in other embodiments, one or more of the actuators within the serial tool tip positioning assembly may be arranged differently in any other suitable or desired manner. Typically, the serial tool tip positioning assembly is used when the tool being used includes a mechanical structure (e.g., router bit, drill bit, tool bit, grinding bit, blade, etc.). Also, the serial tool tip positioning assembly can be used when the tool being used includes a flow or jet of a substance (e.g., water, air, sand or other abrasive particles, paint, metal powder, etc. or any combination thereof) ejected from, for example, a nozzle or head.

[0046] From the above perspective, each of the relatively high-bandwidth X-axis actuator 108, relatively high-bandwidth Y-axis actuator 110, and relatively high-bandwidth Z-axis actuator 112 within the serial tool tip positioning assembly may be one or more linear stages (e.g., direct drive stage, lead screw stage, ball screw stage, belt drive stage, etc.) driven by one or more hydraulic cylinders, one or more pneumatic cylinders, one or more servo motors, one or more voice coil actuators, one or more piezoelectric actuators, one or more electrostrictive elements, etc., or any combination thereof. It should be understood that any of the relatively high-bandwidth X-axis actuator 108, relatively high-bandwidth Y-axis actuator 110, and relatively high-bandwidth Z-axis actuator 112 within the serial tool tip positioning assembly may be configured to provide continuous motion or stepped (incremental) motion.

[0047] For maintaining, holding, transferring, etc. a mechanical structure (e.g., router bit, drill bit, tool bit, grinding bit, blade, etc.) in any suitable or desired manner, a tool fixture (not shown) may be mechanically coupled to the serial tool tip positioning assembly (e.g., in the relatively high-bandwidth Z-axis actuator 112). Thus, the mechanical structure can be coupled to the serial tool tip positioning assembly by the tool fixture. The tool fixture may be one or more chucks or other clamps, clips, or other fixing devices (e.g., bolts, screws, retaining rings, straps, connecting members, etc.). When the tool used involves a flow or jet of a substance (e.g., water, air, sand or other abrasive particles, paint, metal powder, etc., or any combination thereof, supplied by a source of water, air, sand, particles, paint, powder, etc., or a combination thereof as known in the art), nozzles, heads, etc. through which the flow or jet ejects are characterized as the tool fixture.

[0048] ii. Embodiments related to a parallel tool tip positioning assembly In one embodiment, when the tool used is a directed energy beam or the like, a parallel tool tip positioning assembly can be used. Within the parallel tool tip positioning assembly, the properties and configurations of one or more of the relatively high bandwidth X-axis actuator 108, relatively high bandwidth Y-axis actuator 110, and relatively high bandwidth Z-axis actuator 112 depend on the tool being used.

[0049] For example, when the tool used is a beam of electrons or ions (e.g., generated from an electron source or ion source as known in the art), the relatively high bandwidth X-axis actuator 108, relatively high bandwidth Y-axis actuator 110, and relatively high bandwidth Z-axis actuator 112 may be one or more magnetic lenses, cylindrical lenses, einzel lenses, quadrupole lenses, multipole lenses, etc., or any combination thereof.

[0050] In other examples, when the tool being used is a laser beam (e.g., appearing as a series of pulses generated from one or more laser sources as known in the art, or as a continuous or quasi - continuous laser beam, or any arbitrary combination thereof), each of the relatively high - bandwidth X - axis actuator 108 and relatively high - bandwidth Y - axis actuator 110 can be a galvanometer - driven mirror system, a fast - steering mirror system (e.g., a mirror driven by a voice - coil motor, a piezoelectric actuator, an electro - striction actuator, a magneto - striction actuator, etc.), a micro - electro - mechanical system (MEMS) mirror system, an adaptive - optics (AO) system, an electro - optic deflector (EOD) system, an acousto - optic deflector (AOD) system (e.g., arranged and configured to diffract a laser beam along an axis such as the X - axis or Y - axis in response to an applied RF signal), or any arbitrary combination thereof. When the tool is provided as a focused beam of laser light (in which case the "tool tip" is the region of the focused beam having a fluence high enough to machine the workpiece), the relatively high - bandwidth Z - axis actuator 112 can be one or more AOD systems (e.g., arranged and configured to diffract a laser beam along two axes such as the X - axis and Y - axis in response to one or more chirped applied RF signals), a fixed - focal - length lens arranged in the path (i.e., the "propagation path") along which the laser beam propagates, the fixed - focal - length lens being coupled to an actuator (e.g., a voice - coil) configured to move the lens along the propagation path, a variable - focal - length lens arranged in the propagation path (e.g., a zoom lens, or a so - called "liquid lens" incorporating technologies currently provided by COGNEX, VARIOPTIC, etc.), or any arbitrary combination thereof.

[0051] FIG. 3 schematically shows an embodiment of a parallel tool tip positioning assembly configured to position or move a tool tip associated with a focused beam of laser light. Referring to FIG. 3, the parallel tool tip positioning assembly 300 includes a scan lens 302 (e.g., an f-theta lens, a telecentric lens, an axicon lens, etc.) configured to focus a laser light beam propagating along a propagation path 304 deflected by a first galvanometer-driven mirror system (here, a relatively high-bandwidth X-axis actuator 108) and a second galvanometer-driven mirror system (here, a relatively high-bandwidth Y-axis actuator 110), as needed. As shown, the first galvanometer-driven mirror system includes a mirror 306a coupled (e.g., via a shaft) to a motor 308a configured to rotate the mirror 306a about the Y-axis (e.g., to enable deflection of the laser light beam along the X-axis). Similarly, the second galvanometer-driven mirror system includes a mirror 306b coupled (e.g., via a shaft) to a motor 308b configured to rotate the mirror 306b about the X-axis (e.g., to enable deflection of the laser light beam along the Y-axis). As a relatively high-bandwidth Z-axis actuator 112, the parallel tool tip positioning assembly 300 may include a lens coupled to an actuator (e.g., a voice coil (not shown)) configured to move the lens along the propagation path 304 in the direction indicated by the double-sided arrow 310.

[0052] In some cases, the functions provided by two or more of the relatively high-bandwidth X-axis actuator 108, relatively high-bandwidth Y-axis actuator 110, and relatively high-bandwidth Z-axis actuator 112 can be provided by the same system. For example, systems such as a first steering mirror system, a MEMS mirror system, an AO system, etc. can be driven to deflect the laser light along the X-axis and Y-axis. Systems such as a MEMS mirror system, an AO system, and a pair of AOD systems (for example, an AOD system arranged and configured to deflect the laser light along the X-axis and another AOD system arranged and configured to deflect the laser light along the Y-axis) can be driven to deflect the laser light along the X-axis and Y-axis and change the size of the spot irradiated by the laser light in the machining area (thereby effectively changing the position of the beam waist of the focused laser light transmitted to the workpiece during machining along the Z-axis). Therefore, such a system can be characterized as a relatively high-bandwidth X-axis actuator 108, a relatively high-bandwidth Y-axis actuator 110, a relatively high-bandwidth Z-axis actuator 112, or any combination thereof, depending on the form in which the actuator is provided and driven.

[0053] iii. Embodiments related to a hybrid tool tip positioning assembly In one embodiment, when the tool used is a directed energy beam or the like, a hybrid tool tip positioning assembly can be used. For example, when provided as a system such as a galvanometer-driven mirror system, a first steering mirror system (e.g., a mirror driven by a voice coil motor, a piezoelectric actuator, an electrostrictive actuator, a magnetostrictive actuator, etc.), a MEMS mirror system, an AO system, an EOD system, an AOD system, etc., a relatively high bandwidth X-axis actuator 108 and / or a relatively high bandwidth Y-axis actuator 110 may be mounted or mechanically coupled to a relatively high bandwidth Z-axis actuator 112 (e.g., such that it is movable by a relatively high bandwidth Z-axis actuator 112). In this example, the relatively high bandwidth Z-axis actuator 112 may be one or more stages driven by one or more hydraulic cylinders, one or more pneumatic cylinders, one or more servo motors, one or more voice coil actuators, one or more piezoelectric actuators, one or more electrostrictive elements, etc., or any combination thereof (e.g., a direct drive stage, a lead screw stage, a ball screw stage, a belt drive stage, etc.).

[0054] In other examples, when provided as a system such as a MEMS mirror system, an AO system, or a pair of AOD systems, the relatively high-bandwidth Z-axis actuator 112 may be mounted or mechanically coupled to one of the relatively high-bandwidth X-axis actuator 108 and the relatively high-bandwidth Y-axis actuator 110, and that one actuator may in turn be mounted or mechanically coupled to the other of the relatively high-bandwidth X-axis actuator 108 and the relatively high-bandwidth Y-axis actuator 110. In this example, each of the relatively high-bandwidth X-axis actuator 108 and the relatively high-bandwidth Y-axis actuator 110 may be one or more stages (e.g., a direct drive stage, a lead screw stage, a ball screw stage, a belt drive stage, etc.) driven by one or more hydraulic cylinders, one or more pneumatic cylinders, one or more servo motors, one or more voice coil actuators, one or more piezoelectric actuators, one or more electrostrictive elements, etc., or any combination thereof.

[0055] C. Addendum related to a workpiece positioning assembly and a tool tip positioning assembly Notwithstanding the above, any of the relatively low bandwidth actuators described above may be additionally or alternatively incorporated as part of a tool tip positioning assembly (e.g., for positioning and / or moving a tool tip) within a workpiece positioning assembly (e.g., for positioning and / or moving a workpiece). Further, notwithstanding the above, in some embodiments, the workpiece positioning assembly may be any 5-axis workpiece positioning / moving assembly currently available in the art, such as the AGIECHARMILLES laser product line provided by GF MACHINING SOLUTIONS MANAGEMENT, the MICROLUTION ML-D provided by MICROLUTION, or the LASERTEC product line provided by DMG MORI AKIENGESELLSHAFT / DMG MORI CO., LTD. In one embodiment, the workpiece positioning assembly may be as described in FIGS. 4A-4C of U.S. Patent No. 8,392,002 described above. Similarly, notwithstanding the above, in some embodiments, the tool tip positioning assembly may be any laser scan or focusing assembly currently available in the art, such as a 3-axis scan system provided by CAMBRIDGE TECHNOLOGY, the MINISCAN, SUPERSCAN, AXIALSCAN, and FOCUSSHIFER product lines provided by RAYLASE, the MD series 3-axis hybrid laser marker product line provided by KEYENCE CORPORATION, the series of scan heads WOMBAT, ANTEATER, ELEPHANT, PRECESSION ELEPHANT, and PRECESSION ELEPHANT 2 provided by ARGES, or the LASERTEC product line provided by DMG MORI AKIENGESELLSHAFT / DMG MORI CO., LTD.Furthermore, notwithstanding the above, in certain embodiments, the tool tip positioning assembly may be of the type described in U.S. Patent No. 8,121,717, or as described in International Publication No. WO 2014 / 009150 A1 (each of this U.S. Patent and International Publication is hereby incorporated by reference in its entirety), or as described in FIGS. 5A - 5C of the above - mentioned U.S. Patent No. 8,392,002.

[0056] In the above, certain components of an embodiment of the multi - axis machine tool have been illustratively described. Next, with reference to FIG. 1, an algorithm for processing and generating actuator commands for controlling the multi - axis machine tool, which is realized by the control system 100, will be described in more detail.

[0057] D. Embodiments related to the processing of actuator commands Referring to FIG. 1, the control system 100 receives a preliminary actuator command (e.g., obtained or acquired from a computer file or computer program as described above). As shown, the preliminary actuator command includes a preliminary linear actuator command including a preliminary X-axis actuator command (i.e., X_prelim.), a preliminary Y-axis actuator command (i.e., Y_prelim.), and a preliminary Z-axis actuator command (i.e., Z_prelim.), and a preliminary rotary actuator command including a preliminary B-axis actuator command (i.e., B_prelim.) and a preliminary C-axis actuator command (i.e., C_prelim.). In one embodiment, at least one of the preliminary actuator commands has a non-negligible frequency component that exceeds the threshold frequency of the corresponding relatively low-bandwidth actuator. For example, the preliminary X-axis actuator command (i.e., X_prelim.) may have a non-negligible frequency component that exceeds the threshold frequency of the corresponding relatively low-bandwidth X-axis actuator 102, the preliminary Y-axis actuator command (i.e., Y_prelim.) may have a non-negligible frequency component that exceeds the threshold frequency of the corresponding relatively low-bandwidth Y-axis actuator 104, the preliminary Z-axis actuator command (i.e., Z_prelim.) may have a non-negligible frequency component that exceeds the threshold frequency of the corresponding relatively low-bandwidth Z-axis actuator 106, the preliminary B-axis actuator command (i.e., B_prelim.) may have a non-negligible frequency component that exceeds the threshold frequency of the corresponding relatively low-bandwidth B-axis actuator 114, the preliminary C-axis actuator command (i.e., C_prelim.) may have a non-negligible frequency component that exceeds the threshold frequency of the corresponding relatively low-bandwidth C-axis actuator 116, or any combination thereof. However, it should be understood that any or all of the above-described preliminary actuator commands may have a non-negligible frequency component at or below the threshold frequency of the corresponding relatively low-bandwidth actuator.

[0058] The preliminary actuator commands are processed and a first set of intermediate linear actuator commands is generated. For example, inverse kinematic transformation 118 is applied to the preliminary X-axis actuator command (i.e., X_prelim.), the preliminary Y-axis actuator command (i.e., Y_prelim.), the preliminary Z-axis actuator command (i.e., Z_prelim.), the preliminary B-axis actuator command (i.e., B_prelim.), and the preliminary C-axis actuator command (i.e., C_prelim.) to generate a first set of intermediate linear actuator commands. The first set of intermediate linear actuator commands includes a first intermediate X-axis actuator command (i.e., X0), a first intermediate Y-axis actuator command (i.e., Y0), and a first intermediate Z-axis actuator command (i.e., Z0). The inverse kinematic transformation can be applied by the following equation.

Equation

[0059] Preliminary rotary actuator commands (e.g., preliminary B-axis actuator command B_prelim. and preliminary C-axis actuator command C_prelim.) are input into processing stage 120, and one or more processed rotary actuator commands are generated. In the illustrated embodiment, B_low means a processed B-axis actuator command, and C_low means a processed C-axis actuator command. Both are generated at processing stage 120. At processing stage 120, for example, applying one or more suitable filters to the preliminary rotary actuator command, modifying the preliminary rotary actuator command by one or more suitable algorithms, reducing the preliminary rotary actuator command, applying one or more low-order interpolations to the preliminary rotary actuator command, or performing one or more processes including any combination thereof can be done to the preliminary rotary actuator command. Examples of suitable filters include digital filters, low-pass filters, Butterworth filters, etc., or any combination thereof. Examples of suitable algorithms include autoregressive moving average algorithms. The processed rotary actuator command corresponds to the preliminary rotary actuator command but does not have (or has only a negligible amount of) frequency components exceeding the threshold frequency of the corresponding rotary actuator. Thus, the processed B-axis actuator command (i.e., B_low) does not have (or has only a negligible amount of) frequency components exceeding the threshold frequency of the relatively low-bandwidth B-axis actuator 114, and the processed C-axis actuator command (i.e., C_low) does not have (or has only a negligible amount of) frequency components exceeding the threshold frequency of the relatively low-bandwidth C-axis actuator 116. As used herein, each of the processed rotary actuator commands described above is referred to herein as a "low-frequency component rotary actuator command" or more generally a "low-frequency component actuator command".

[0060] The first set of intermediate linear actuator commands and the processed rotary commands are processed to generate a second set of intermediate linear actuator commands. For example, a forward kinematic transformation 122 is applied to the first intermediate X-axis actuator command (i.e., X0), the first intermediate Y-axis actuator command (i.e., Y0), the first intermediate Z-axis actuator command (i.e., Z0), the processed B-axis actuator command (i.e., B_low), and the processed C-axis actuator command (i.e., C_low) to generate a second set of intermediate linear actuator commands. The second set of intermediate linear actuator commands includes a second intermediate X-axis actuator command (i.e., X1), a second intermediate Y-axis actuator command (i.e., Y1), and a second intermediate Z-axis actuator command (i.e., Z1). The forward kinematic transformation can be applied by the following equation.

Number

[0061] A second set of intermediate linear actuator commands (e.g., a second intermediate X-axis actuator command X1, a second intermediate Y-axis actuator command Y1, and a second intermediate Z-axis actuator command Z1) is input to processing stage 124, and a first set of processed linear actuator commands is generated. The first set of processed linear actuator commands can include a low-frequency component X-axis actuator command (i.e., X_low), a low-frequency component Y-axis actuator command (i.e., Y_low), and a low-frequency component Z-axis actuator command (i.e., Z_low). In processing stage 124, for example, applying one or more suitable filters to the second intermediate linear actuator commands, modifying the second intermediate linear actuator commands by one or more suitable algorithms, reducing the second intermediate linear actuator commands, applying one or more low-order interpolations to the second intermediate linear actuator commands, or the like, or performing one or more processes including any combination thereof can be done on the second intermediate linear actuator commands. Examples of suitable filters include digital filters, low-pass filters, Butterworth filters, etc., or any combination thereof. Examples of suitable algorithms include autoregressive moving average algorithms. The processed linear actuator commands correspond to the preliminary linear actuator commands but do not have (or have only a negligible amount of) frequency components that exceed the threshold frequency of the corresponding linear actuator. Thus, the low-frequency component X-axis actuator command (i.e., X_low) does not have (or has only a negligible amount of) frequency components that exceed the threshold frequency of the X-axis actuator 102 with a relatively low bandwidth, the low-frequency component Y-axis actuator command (i.e., Y_low) does not have (or has only a negligible amount of) frequency components that exceed the threshold frequency of the Y-axis actuator 104 with a relatively low bandwidth, and the low-frequency component Z-axis actuator command (i.e., Z_low) does not have (or has only a negligible amount of) frequency components that exceed the threshold frequency of the Z-axis actuator 106 with a relatively low bandwidth.

[0062] The low-frequency component linear actuator commands (e.g., X_low, Y_low, and Z_low) are subtracted from the corresponding actuator commands in the second set of intermediate linear actuator commands to generate a second set of processed linear actuator commands. The second set of processed linear actuator commands can include a high-frequency component X-axis actuator command (i.e., X_high), a high-frequency component Y-axis actuator command (i.e., Y_high), and a high-frequency component Z-axis actuator command (i.e., Z_high). For example, the low-frequency component X-axis actuator command (i.e., X_low) can be subtracted from the second intermediate X-axis actuator command (i.e., X1) to obtain the high-frequency component X-axis actuator command (i.e., X_high), the low-frequency component Y-axis actuator command (i.e., Y_low) can be subtracted from the second intermediate Y-axis actuator command (i.e., Y1) to obtain the high-frequency component Y-axis actuator command (i.e., Y_high), and the low-frequency component Z-axis actuator command (i.e., Z_low) can be subtracted from the second intermediate Z-axis actuator command (i.e., Z1) to obtain the high-frequency component Z-axis actuator command (i.e., Z_high). The above-described subtraction can be performed by an adder 126, and the adder 126 can be implemented by a suitable or desired method known in the art. Typically, the high-frequency component X-axis actuator command (i.e., X_high) has a frequency component that exceeds the threshold frequency of the relatively low-bandwidth X-axis actuator 102 but is below the threshold frequency of the relatively high-bandwidth X-axis actuator 108. Similarly, the high-frequency component Y-axis actuator command (i.e., Y_high) has a frequency component that exceeds the threshold frequency of the relatively low-bandwidth Y-axis actuator 104 but is below the threshold frequency of the relatively high-bandwidth Y-axis actuator 110, and the high-frequency component Z-axis actuator command (i.e., Z_high) has a frequency component that exceeds the threshold frequency of the relatively low-bandwidth Z-axis actuator 106 but is below the threshold frequency of the relatively high-bandwidth Z-axis actuator 112.

[0063] Finally, as shown, the low-frequency component X-axis actuator command (i.e., X_low), the low-frequency component Y-axis actuator command (i.e., Y_low), the low-frequency component Z-axis actuator command (i.e., Z_low), the high-frequency component X-axis actuator command (i.e., X_high), the high-frequency component Y-axis actuator command (i.e., Y_high), the high-frequency component Z-axis actuator command (i.e., Z_high), the low-frequency component B-axis actuator command (i.e., B_low), and the low-frequency component C-axis actuator command (i.e., C_low) are output to the X-axis actuator 102 with a relatively low bandwidth, the Y-axis actuator 104 with a relatively low bandwidth, the Z-axis actuator 106 with a relatively low bandwidth, the X-axis actuator 108 with a relatively high bandwidth, the Y-axis actuator 110 with a relatively high bandwidth, the Z-axis actuator 112 with a relatively high bandwidth, the B-axis actuator 114, and the C-axis actuator 116, respectively.

[0064] Although not shown, the control system 100 compensates for processing delays or transmission delays that occur when generating low-frequency component X-axis actuator commands (i.e., X_low), low-frequency component Y-axis actuator commands (i.e., Y_low), low-frequency component Z-axis actuator commands (i.e., Z_low), high-frequency component X-axis actuator commands (i.e., X_high), high-frequency component Y-axis actuator commands (i.e., Y_high), high-frequency component Z-axis actuator commands (i.e., Z_high), low-frequency component B-axis actuator commands (i.e., B_low), and low-frequency component C-axis actuator commands (i.e., C_low), and / or when outputting any of these actuator commands to their respective actuators. As a result, the actuator commands can be output synchronously or in cooperation. When outputting the actuator commands synchronously or in cooperation, the actuators essentially react or respond synchronously or in cooperation as well, causing a relative movement between the tool tip and the workpiece so as to move the tool tip along a path that coincides with or corresponds to a desired trajectory through the machining area.

[0065] Generally, the control system 100 can be implemented by one or more controllers communicatively coupled to one or more components of a multi-axis machine tool (e.g., one or more of the actuators described above, one or more components that control or operate a tool, or any combination thereof) by one or more wired communication links or wireless communication links such as, for example, USB, Ethernet, Firewire, Wi-Fi, RFID, NFC, Bluetooth, Li-Fi, or any combination thereof. Generally, a controller is characterized as including one or more processors configured to execute instructions to process and generate the actuator commands described above. The processor may be a programmable processor configured to execute instructions (e.g., including one or more general-purpose computer processors, microprocessors, digital signal processors, or any combination thereof). Instructions executable by the processor may be implemented in a suitable form such as software, firmware, or the like, or circuits including programmable logic devices (PLDs), field programmable gate arrays (FPGAs), field programmable object arrays (FPOAs), application specific integrated circuits (ASICs) (including digital circuits, analog circuits, analog / digital hybrid circuits), or any arbitrary combination thereof. Execution of the instructions may be performed on one processor, distributed among multiple processors, performed in parallel across multiple processors within one device or across a network of devices, or any arbitrary combination thereof. In one embodiment, the controller includes a tangible medium such as a computer memory accessible by the processor (e.g., via one or more wired communication links or wireless communication links).As used herein, "computer memory" includes magnetic media (e.g., magnetic tape, hard disk drive, etc.), optical disks, volatile or non-volatile semiconductor memories (e.g., RAM, ROM, NAND-type flash memory, NOR-type flash memory, SONOS memory, etc.), etc., and can be locally accessible, or remotely accessible (e.g., through a network), or a combination thereof. Generally, instructions can be stored as computer software (e.g., executable code, files, instructions, etc., library files, etc.). This computer software can be written in, for example, C, C++, Visual Basic, Java, Python, Tel, Perl, Scheme, Ruby, etc., and can be easily created by those skilled in the art from the descriptions provided herein. Computer software is generally stored within one or more data structures transmitted by the computer memory.

[0066] Although not shown, one or more drivers (e.g., RF driver, servo driver, line driver, power supply, etc.) are communicably coupled to the input of one or more of the above-described actuators, one or more components that control or operate the tool, or any arbitrary combination thereof. Typically, each driver includes an input to which a controller is communicably coupled. Thus, the controller can generate one or more control signals (e.g., actuator commands, tool control commands, etc.) that can be transmitted to the inputs of one or more drivers associated with one or more components of the multi-axis machine tool. Upon receiving the control signal, the driver typically supplies current to the connected component (e.g., actuator, tool, etc.) to operate the component and produce an effect corresponding to the command signal. Thus, components such as the above-described actuators, tools, etc. are adapted to respond to command signals (e.g., actuator commands, tool control commands, etc.) generated and output by the controller.

[0067] From the above perspective, it can be understood that the control system 100 can be utilized to continuously synchronize and coordinate the operations of relatively low-bandwidth actuators (e.g., having a relatively large motion range) and relatively high-bandwidth actuators (e.g., having a relatively small motion range) of a multi-axis machine tool to position or move the tooling area relative to the workpiece (e.g., to accurately and reliably correspond to a desired trajectory). The control system 100 can accurately position the tooling area relative to the workpiece (e.g., according to a desired trajectory), but the final tooling angle that appears at any point during workpiece machining may deviate from the reference tooling angle (e.g., specified explicitly or implicitly by the trajectory). Generally, a tooling angle deviation occurs when the high-frequency component linear actuator command has a frequency component exceeding the threshold frequency of the rotary actuator that is not part of a set of redundant rotary actuators. However, such a tooling angle deviation can be calculated in advance (e.g., based on the characteristics of the actuators within the multi-axis machine tool or based on the desired trajectory, etc.) and can be compensated for (completely or partially) during workpiece machining (e.g., by adjusting the moving speed of the tooling area relative to the workpiece or by adjusting the machining at one or more of the processing stages 120 and 124).

[0068] III. Control of a multi-axis machine tool having axially complementary actuators and redundant rotary actuators FIG. 4 is a block diagram schematically showing a control system 400 for controlling a multi-axis machine tool including an actuator as exemplarily described above with respect to FIGS. 1 to 3 according to an embodiment. However, in the present embodiment, the multi-axis machine tool may additionally include a B-axis actuator 402, a C-axis actuator 404, or both the B-axis actuator 402 and the C-axis actuator 404. The threshold frequency of the B-axis actuator 402 is higher than the threshold frequency of the B-axis actuator 114. Therefore, in the present specification, the B-axis actuator 114 can also be referred to as a "B-axis actuator with a relatively low bandwidth", and in the present specification, the B-axis actuator 402 can also be referred to as a "B-axis actuator with a relatively high bandwidth". Similarly, the threshold frequency of the C-axis actuator 404 is higher than the threshold frequency of the C-axis actuator 116. Therefore, in the present specification, the C-axis actuator 116 can also be referred to as a "C-axis actuator with a relatively low bandwidth", and in the present specification, the C-axis actuator 404 can also be referred to as a "B-axis actuator with a relatively high bandwidth".

[0069] The relatively low-bandwidth B-axis actuator 114 and the relatively high-bandwidth B-axis actuator 114 each constitute a set of redundant actuators (i.e., a set of redundant B-axis actuators). Similarly, a set of redundant actuators is constituted by each pair of the relatively low-bandwidth C-axis actuator 116 and the relatively high-bandwidth C-axis actuator 404 (i.e., a set of redundant C-axis actuators). The illustrated embodiment describes a multi-axis machine tool having a set of redundant actuators constituted by only two rotary actuators, but the multi-axis machine tool may further include one or more additional rotary actuators arranged or configured to cause movement along either the B-axis or the C-axis, and it will be understood that any set of redundant actuators may include three or more rotary actuators.

[0070] In one embodiment, a relatively high bandwidth B-axis actuator 402, considered together with one or more actuators in a redundant X-axis actuator set and / or one or more actuators in a redundant Z-axis actuator set, constitutes a set of axially complementary actuators. In other embodiments, a relatively high bandwidth C-axis actuator 404, considered together with one or more actuators in a redundant X-axis actuator set and / or one or more actuators in a redundant Y-axis actuator set, constitutes a set of axially complementary actuators. In still other embodiments, relatively high bandwidth B-axis actuator 402 and C-axis actuator 404, each considered together with one or more actuators in a redundant X-axis actuator set, one or more actuators in a redundant Y-axis actuator set, and / or one or more actuators in a redundant Z-axis actuator set, constitute a set of axially complementary actuators.

[0071] A. Embodiments related to a tool tip positioning assembly In one embodiment, one or both of the relatively high bandwidth B-axis actuator 402 and the relatively high bandwidth C-axis actuator 404 may be incorporated into the tool tip positioning assembly illustratively described above. As a result, the tool tip associated with the multi-axis machine tool can be positioned or moved simultaneously or non-simultaneously along the B-axis and / or C-axis in addition to the X-axis, Y-axis, Z-axis, or any combination thereof, so that the tool tip positioning assembly can be configured. However, it should be understood that one or more of the relatively high bandwidth X-axis actuator 108, relatively high bandwidth Y-axis actuator 110, relatively high bandwidth Z-axis actuator 112, relatively high bandwidth B-axis actuator 402, and relatively high bandwidth C-axis actuator 404 may be omitted from the tool tip positioning assembly when appropriate or as necessary. As described above, a tool tip positioning assembly including one or both of the relatively high bandwidth B-axis actuator 402 and the relatively high bandwidth C-axis actuator 404 can be characterized as a "serial tool tip positioning assembly", a "parallel tool tip positioning assembly", or a "hybrid tool tip positioning assembly" (e.g., combining the characteristics specific to the serial tool tip positioning assembly and the parallel tool tip positioning assembly).

[0072] i. Embodiments related to a serial tool tip positioning assembly In a serial tool tip positioning assembly (such as described above), either the relatively high bandwidth B-axis actuator 402 or the relatively high bandwidth C-axis actuator 404 may include one or more elements (e.g., stages, fixtures, chucks, rails, bearings, brackets, clamps, straps, bolts, screws, pins, retaining rings, connecting members, etc. (not shown)) that allow the relatively high bandwidth B-axis actuator 402 and the relatively high bandwidth C-axis actuator 404 to be attached or mechanically coupled to each other or to any of the above-described actuators included within the serial tool tip.

[0073] The relatively high bandwidth B-axis actuator 402 and the relatively high bandwidth C C-axis actuator 404 within the serial tool tip positioning assembly may each be one or more rotational stages (such as a direct drive stage, a lead screw stage, a ball screw stage, a belt drive stage, etc.) driven by one or more hydraulic cylinders, one or more pneumatic cylinders, one or more servo motors, one or more voice coil actuators, one or more piezoelectric actuators, one or more electrostrictive elements, etc., or any combination thereof. Also, either the relatively high bandwidth B-axis actuator 402 or the relatively high bandwidth C-axis actuator 404 within the serial tool tip positioning assembly may be configured to provide continuous motion or stepped (incremental) motion.

[0074] A tool fixture (not shown) may be mechanically coupled to the serial tool tip positioning assembly by the relatively high bandwidth Z-axis actuator 112 (described above), or by the relatively high bandwidth B-axis actuator 402, or by the relatively high bandwidth C-axis actuator 404 to maintain, hold, transfer, etc. a mechanical structure (such as a router bit, a drill bit, a tool bit, a grinding bit, a blade, etc.), another structure from which a flow or jet exits (such as a nozzle, a head, etc.) in any suitable or desired manner.

[0075] ii. Embodiments related to a parallel tool tip positioning assembly In one embodiment, the parallel tool tip positioning assembly includes a relatively high bandwidth C-axis actuator 404 in addition to one or more of the relatively high bandwidth X-axis actuator 108, relatively high bandwidth Y-axis actuator 110, and relatively high bandwidth Z-axis actuator 112 illustratively described above. In this case, the configuration of the relatively high bandwidth C-axis actuator 404 depends on the tool being used. The examples of embodiments described below relate to an example where the tool being used includes laser light (e.g., appearing as a series of pulses, or as a continuous or quasi-continuous laser light beam, or any combination thereof, generated from one or more laser sources known in the art).

[0076] When the tool being used is laser light, the laser light can be directed to irradiate the machining area or a portion of the workpiece in the vicinity thereof (e.g., along the propagation path described above). Looking at the surface of the workpiece, or in a plane orthogonal to the portion of the propagation path that intersects the workpiece in the machining area, the spatial intensity distribution of the laser light at the irradiated portion (also referred to as a "spot") can be characterized as having a circular or non-circular shape. Examples of non-circular shapes include elliptical, triangular, square, rectangular, irregular shapes, and the like. The circular or non-circular spot shape can be generated by suitable methods known in the art using one or more beam-clipping apertures, diffractive optical elements, AOD systems, prisms, lenses, etc. (which can be included as part of a multi-axis machine tool and can be placed in the propagation path), or can be generated as a result of the laser light beam irradiating the surface of the workpiece in a machining area that is non-flat or not orthogonal to the portion of the propagation path that intersects the workpiece in the machining area, or a combination thereof.

[0077] From the above perspective, a relatively high-bandwidth C-axis actuator 404 can be placed at any suitable or desired position "upstream" or as required "downstream" within the propagation path, depending on the need, of either a relatively high-bandwidth X-axis actuator 108 or a relatively high-bandwidth Y-axis actuator 110 within a parallel tool tip positioning assembly (e.g., parallel tool tip positioning assembly 300). In one embodiment, the relatively high-bandwidth C-axis actuator 404 can be a microelectromechanical system (MEMS) mirror system, an adaptive optics (AO) system, or any arbitrary combination thereof, and can be configured to change the shape of the spatial intensity distribution with respect to the propagation path by effectively changing the orientation of the spatial intensity distribution of the incident laser light beam. In other embodiments, the relatively high-bandwidth C-axis actuator 404 can be one or more prisms, and this prism can be rotated (e.g., about an axis along which the propagation path extends) or moved by an actuator to change the orientation of the spatial energy distribution with respect to the propagation path. In one embodiment, the relatively high-bandwidth C-axis actuator 404 may be as described in U.S. Patent No. 6,362,454. This patent is incorporated herein by reference. In still other embodiments, the relatively high-bandwidth C-axis actuator 404 can be one or more acou-optic deflector (AOD) systems (e.g., arranged and configured to diffract laser light along two axes such as the X-axis and the Y-axis in response to one or more chirped applied RF signals).

[0078] In some cases, the functions provided by the relatively high-bandwidth C-axis actuator 404 and one or more of the relatively high-bandwidth X-axis actuator 108, relatively high-bandwidth Y-axis actuator 110, and relatively high-bandwidth Z-axis actuator 112 can be provided by the same system. For example, driving systems such as a MEMS mirror system, an AO system, and a pair of AOD systems (for example, one AOD system arranged and configured to diffract laser light along the X-axis and another AOD system arranged and configured to diffract laser light along the Y-axis) to diffract laser light along the X-axis and Y-axis and change the size of the spot irradiated by the laser light in the machining area (thereby effectively changing the position of the beam waist of the focused laser light irradiated on the workpiece during processing along the Z-axis), and the orientation of the spatial energy distribution of the laser beam with respect to the propagation path can be changed. Therefore, such a system can be characterized as the relatively high-bandwidth X-axis actuator 108, relatively high-bandwidth Y-axis actuator 110, relatively high-bandwidth Z-axis actuator 112, relatively high-bandwidth C-axis actuator 404, or any combination thereof, depending on the installation method and driving method.

[0079] iii. Embodiments related to a hybrid tool tip positioning assembly In one embodiment, the hybrid tool tip positioning assembly includes a relatively high bandwidth B-axis actuator 402 in addition to one or more of the relatively high bandwidth X-axis actuator 108, relatively high bandwidth Y-axis actuator 110, relatively high bandwidth Z-axis actuator 112, and relatively high bandwidth C-axis actuator 404 illustratively described above in connection with the serial tool tip positioning assembly. In this case, the relatively high bandwidth B-axis actuator 402 is attached to and thereby made movable by one or more of the above-described actuators such that it can move simultaneously or non-simultaneously along the X-axis, Y-axis, Z-axis, C-axis, or an axis arbitrarily combining these. It will be understood that the configuration of the relatively high bandwidth B-axis actuator 402 depends on the tool being used. The examples of the embodiments described below are relevant when the tool being used includes laser light (e.g., appearing as a series of pulses, or as a continuous or quasi-continuous laser light beam, or an arbitrary combination thereof, generated from one or more laser sources known in the art). When the tool being used is laser light, the laser light can be directed (e.g., along the propagation path described above) to irradiate a portion of the workpiece on or near the turning area.

[0080] Next, referring to FIG. 5, the relatively high bandwidth B-axis actuator 402 includes a first AOD system 500 arranged and configured to diffract laser light along an axis (e.g., along the X-axis) in response to an applied RF signal, and a second AOD system as needed. 1 of the AOD system 500It can include a second AOD system 502 that is arranged and installed on the "downstream side" and is configured to diffract the laser light along another axis (for example, along the Y axis) in response to the applied RF signal. The relatively high-bandwidth B-axis actuator 402 can include additional components such as half-wave plates 501 and 503, a polarization beam splitter 505, etc. When driven, the first AOD system 500 and the second AOD system 502 can deflect the incident beam of the laser light 510 or move it to any number of positions within the scan range associated with the first AOD system 500 and the second AOD system 502 (for example, as shown by the deflected beams 512 and 514). Deflected beams such as the deflected beams 512 and 514 can be characterized by the deflection angles measured with respect to the incident beam of the laser light 510.

[0081] Also, the relatively high-bandwidth B-axis actuator 402 can include a set of lenses (for example, relay lens 504 and scan lens 506) that are arranged on the downstream side of the second AOD system 502 as needed. The relay lens 504 is used to convert the deflection angle of the deflected beam (for example, the deflected beams 512 and 514) into a beam (for example, the laterally shifted beams 512' and 514') that is laterally shifted on the scan lens 506. Then, the scan lens 506 converts the laterally shifted beam (for example, the laterally shifted beams 512' and 514') into an incident beam (for example, the incident beams 512” and 514”) that is transmitted to the workpiece (illustrated here at 508). As shown, the incident beams 512” and 514” are the same of ( or at least substantially the same ) spot or touring area region and irradiate the workpiece at different touring angles.

[0082] Based on the configuration of the relatively high bandwidth B-axis actuator 402 described above, it should be understood that the speed at which the turning angle of the incident beam of the laser light can be changed corresponds to the refresh rates of the first AOD system 500 and the second AOD system 502. The maximum turning angle is proportional to the AOD deflection range and the focal length of the relay lens 504, and inversely proportional to the focal length of the scan lens 506. By adjusting the distance between the relay lens 504 and the scan lens 506, different incident beams can be reliably irradiated onto the same turning area on the workpiece 508.

[0083] B. Addendum related to a tool tip positioning assembly Notwithstanding the above, any of the relatively low bandwidth actuators described above as being incorporated within a workpiece positioning assembly (e.g., for positioning and / or moving the workpiece) may additionally or alternatively be incorporated as part of a tool tip positioning assembly that includes a relatively high bandwidth B-axis actuator 402 or a relatively high bandwidth C-axis actuator 404 (e.g., for positioning and / or moving the tool tip). Further, notwithstanding the above, in certain embodiments, it should be understood that the tool tip positioning assembly may be any laser scanning or focusing assembly currently available in the art, such as the PRECESSION ELEPHANT and PRECESSION ELEPHANT 2 series scan heads provided by ARGES. Further, notwithstanding the above, in certain embodiments, it should be understood that the tool tip positioning assembly may be as described in International Publication No. WO 2014 / 009150 A1. This publication is hereby incorporated by reference in its entirety.

[0084] C. Embodiments related to the processing of actuator commands Generally, control system 400 can be implemented by one or more controllers exemplified with respect to control system 100, and the operation of control system 400 is the same as the operation of control system 100 described above with respect to FIG. 1, except that additional processes and operations are introduced due to the presence of relatively high-bandwidth B-axis actuator 402, relatively high-bandwidth C-axis actuator 404, or a combination thereof. These additional processes and operations are described below.

[0085] The low-frequency component rotary actuator commands (e.g., B_low and C_low) are the corresponding actuator commands subtracted in the preliminary rotary actuator commands (e.g., preliminary B-axis actuator command B_prelim. and preliminary C-axis actuator command C_prelim.) to generate one or more further processed rotary actuator commands. For example, subtracting the low-frequency component B-axis actuator command (i.e., B_low) from the preliminary B-axis actuator command (i.e., B_prelim.) can obtain the high-frequency component B-axis actuator command (i.e., B_high) as a further processed rotary actuator command. Similarly, subtracting the low-frequency component C-axis actuator command (i.e., C_low) from the preliminary C-axis actuator command (i.e., C_prelim.) can obtain the high-frequency component C-axis actuator command (i.e., C_high) as a further processed rotary actuator command. The above-described subtraction can be performed by the adder 406, and this adder 406 can be realized by a suitable or desired method known in the art. Typically, the high-frequency component B-axis actuator command (i.e., B_high) has a frequency component that exceeds the threshold frequency of the B-axis actuator 114 with a relatively low bandwidth but is below the threshold frequency of the B-axis actuator 402 with a relatively high bandwidth. Similarly, the high-frequency component C-axis actuator command (i.e., C_high) has a frequency component that exceeds the threshold frequency of the C-axis actuator 116 with a relatively low bandwidth but is below the threshold frequency of the C-axis actuator 404 with a relatively high bandwidth.

[0086] Finally, as shown, the high-frequency component B-axis actuator command (i.e., B_high), the high-frequency component C-axis actuator command (i.e., C_high), or any combination thereof, is output to each of the relatively high-bandwidth B-axis actuator 402 and relatively high-bandwidth C-axis actuator 404. Although not shown, the control system 400 may include one or more delay buffers for compensating for processing delays or transmission delays that occur when generating the high-frequency component B-axis actuator command (i.e., B_high), the high-frequency component C-axis actuator command (i.e., C_high), and / or when outputting any of these actuator commands to their respective actuators. As a result, the illustrated actuator commands can be output synchronously or in cooperation. When outputting the actuator commands synchronously or in cooperation, the actuators essentially react or respond synchronously or in cooperation as well, causing a relative movement between the tool tip and the workpiece to move the tooling area along a path that matches or corresponds to the desired trajectory.

[0087] The foregoing has described embodiments of the present invention and is not to be construed as limiting. Although some specific embodiments and examples have been described with reference to the drawings, those skilled in the art will readily recognize that many modifications are possible to the disclosed embodiments and examples and to other embodiments without departing significantly from the novel teachings and advantages of the present invention. Accordingly, all such modifications are intended to be included within the scope of the invention as defined in the following claims. For example, those skilled in the art will understand that the subject matter of any sentence, paragraph, example, or embodiment can be combined with the subject matter of any other sentence, paragraph, example, or embodiment, except where such combinations are mutually exclusive. Accordingly, the scope of the present invention should be determined by the following claims and the equivalents of the claims to be included therein.

Claims

【Claim 1】 A lens arranged and configured to generate a focused laser beam that propagates along a beam axis and has a beam waist by focusing a laser beam; A linear actuator movable along the beam axis with respect to the lens; At least one positioner movable along the beam axis with respect to the beam waist, the at least one positioner including at least one selected from the group consisting of an acousto-optic deflector (AOD) system, a microelectromechanical system (MEMS) mirror system, and an adaptive optics (AO) system; A controller operably connected to the linear actuator and the at least one positioner; Comprising; The controller: Generates a low-frequency component linear actuator command and a high-frequency component linear actuator command based at least in part on an input linear actuator command, a first output linear output command, and a second output linear output command; Outputs the low-frequency component linear actuator command to the linear actuator; Outputs the high-frequency component linear actuator command to the at least one positioner; Is capable of; Device.

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