Systems and methods for calibrating a microplate gripper

Abstract

Identifying the exact spatial relationship between a gripper and a microplate is accomplished through use of electrical signals corresponding to contact between the gripper and the microplate. An applied voltage on the gripper is maintained until such time as the gripper contacts the microplate, which is kept at a different voltage such as ground. When the gripper contacts the microplate, the gripper's voltage changes in a way that can be read by a controller. By bumping the microplate along multiple axes, or in several expected positions of microplate features, the voltage change can be read to determine the exact relative position between the microplate and the gripper.

Description

[0001] SYSTEMS AND METHODS FOR CALIBRATING A MICROPLATE GRIPPER

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application is being filed on June 27, 2024, as a PCT International Patent Application that claims priority to and the benefit of U.S. Provisional Application No. 63 / 510,573, filed on June 27, 2023, the entire contents of which are incorporated herein by reference.

[0004] INTRODUCTION

[0005] Automated microplate processing systems may include, e.g., imagers, incubators, organoid or cell culturers, or other subsystems. Microplates are moved between the various subsystems as required or desired to perform the various operations associated therewith. Movement of the microplates are performed by robotic grippers that may be subject to mechanical drift. Further, grippers may need to access microplates from other moving subsystems that may themselves drift over time. Calibrating the grippers that move microplates or other hardware is challenging and time-consuming, as they typically require a service technician to teach the correct positions of the gripper. Routine calibration can be used to assess health parameters of the robotic system.

[0006] SUMMARY

[0007] In one aspect, the technology relates to a method of calibrating a microplate gripper having a fork with at least one tine. The method includes moving the tine along a first direction to contact an first surface of a microplate stage with the tine; moving the tine along a second direction to contact a second surface of the microplate stage with the tine; moving the tine along a third direction so as to contact a third surface of the microplate stage with the tine; detecting a signal at each contact between the tine and the microplate stage at the first, second, and third surfaces; and recording a position of the tine at the detection of each of the signals. The detected signals can include a voltage drop at an electrical node coupled to a controller of a motor configured to move the tine relative to the microplate stage in the first, second, and third directions. The detected signals can include a motor current draw in excess of a threshold. The method can further include actuating the motor for each moving of the tine. The method can include terminating a voltage delivery to the motor at the detection of each signal. The method can include retracting the tine along the first direction to terminate contact between the first surface of the microplate and the tine. The can include retracting the tine along the second direction to terminate contact between the second surface of the microplate and the tine. The method can include retracting the tine along the third direction to terminate contact between the third surface of the microplate and the tine. There can be multiple tines, or there can be multiple forks, or both. The method can include comparing the recorded position of the tine at each of the detected signals to a known dataset, and the known dataset can include dimensional data of the microplate stage, or dimensional data of at least one of the fork and the tine, or dimensional data of a known microplate. The method can include adjusting a microplate gripper datum based at least in part on the comparison. The microplate gripper can include multiple forks and the method can include setting a separation distance between the forks. Setting the separation distance can be performed prior to moving the tine along any of the first direction, the second direction, and the third direction. The first direction, the second direction, and the third direction can all be mutually orthogonal one another. The separation distance can be less than a known dimension of the microplate stage. The known dimension can be a smallest dimension of the upper surface of the microplate.

[0008] According to a second aspect, a method of calibrating a position of a microplate gripper relative to a microplate stage is disclosed. The method includes contacting a first surface of the microplate stage with the gripper; contacting a second surface of the microplate stage with the gripper; contacting a third surface of the microplate stage with the gripper, wherein each of the first surface, the second surface, and the third surface are disposed substantially orthogonal to each other; receiving an electrical signal at each contact between the gripper and the microplate stage when contacting each of the first surface, the second surface, and the third surface; recording a position of the gripper at the receipt of each of the signals; and comparing each of the positions to a dimensional data of the microplate gripper and the microplate stage. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The following drawing figures, which form a part of this application, are illustrative of described technology and are not meant to limit the scope of the disclosure as claimed in any manner, which scope shall be based on the claims appended hereto.

[0010] FIG. 1A depicts a front view of a microplate processing system.

[0011] FIG. IB depicts a front perspective view of a portion of the microplate processing system of FIG. 1A, with a microplate gripper extending therefrom.

[0012] FIG. 2 depicts a perspective view of a microplate gripper for use in a microplate processing system.

[0013] FIGS. 3A and 3B depict schematic views of a calibration system for a microplate gripper in a first condition and in a second condition, respectively.

[0014] FIGS. 4A-4G depict a method of calibrating a position of a microplate gripper.

[0015] FIG. 5 depicts another method of calibrating a position of a microplate gripper relative to a microplate stage.

[0016] FIG. 6 depicts a block diagram of a computing device, in accordance with an example of the disclosure.

[0017] DETAILED DESCRIPTION

[0018] FIG. 1A depicts a front view of a microplate processing system 100. The system 100 includes an incubation subsystem 102, which may be used to store one or more microplates under controlled conditions (as to temperature, relative humidity, etc.) therein. The incubation subsystem 102 is adjacent a microplate elevator 104, into which microplates may be loaded and moved to other subsystems. The incubation subsystem 102 may be communicatively coupled to the microplate elevator 104 at an interface 106, through which microplates may be passed via a transport system (not shown). Microplates may be loaded into or removed from one or more access ports 108, which may be located on the elevator 104. The elevator 104 may be used to organize the introduction of microplates to the incubation subsystem 102, as well as to an imaging subsystem 110. The imaging subsystem 110 is communicatively coupled to the elevator 104 via an interface 112, which may be aligned with or mis-aligned from the interface 106.

[0019] The imaging subsystem 110 may include microscopes, lens systems, light sources, cameras, and other components as required or desired to image the contents of the microplates presented thereto. The system 100 is for illustrative purposes only and the subsystems thereof should not be considered limiting to the technology of the present application. Microplate processing systems may also include other subsystems not shown in FIG. 1A, such as culturing subsystems that introduce reagents, cells, or other constituents to the well plate. A culturing subsystem may be integrated into the incubation subsystem 102, the imaging subsystem 110, or may be a dedicated subsystem in a dedicated housing.

[0020] Transferring microplates between the various subsystems (for example, between the incubation subsystem 102 and the elevator 104 or between the elevator 104 and the imaging subsystem 110) requires precise spatial coordination to ensure the transfer occurs carefully without dropping the microplate and automatically, typically without human intervention. The technologies described herein contemplate microplate transfer systems that are highly precise and can operate without human intervention even in the existence of mechanical drift, programming inconsistencies, changes of subsystems or microplates, etc.

[0021] FIG. IB depicts a front perspective view of a portion of the microplate processing system 100 of FIG. 1A, namely the imaging subsystem 110. A microplate gripper 120 extends from an opening 121 in a housing of the imaging subsystem 110. The microplate gripper 120 includes two gripping forks 122a, 122b. that may be manipulated by one or motors disposed in the imaging subsystem 110 to grip a microplate 124.

[0022] For clarity herein, the microplate gripper 120 is described as being supported within the imaging subsystem 110 to transfer microplate 124 between that subsystem 110 and the elevator 104 (FIG. 1A). In other examples, a microplate gripper may transfer microplates between the incubation subsystem 110 and elevator 104, between the elevator 104 and a culturing subsystem (not shown), between a culturing subsystem (not shown) and an incubation subsystem 110, or between any other adjacent subsystems. Microplate grippers may also be a self-contained module (e.g., not supported within any particular subsystem). In general, however, microplate grippers are used to transfer microplate between subsystems with precision and automatically with limited or no human intervention, if properly calibrated.

[0023] The technologies described herein contemplate a system 100 in which the microplate gripper 120 detects a handover position (a location where a microplate stage that holds the microplate 124 will be positioned for transfer) and triggers a signal when the correct position is reached. In an example, the described implementations use the handover position itself as the sensor element. The system is highly integrated and eliminates the need of a specialist to teach the handover position. The system automatically detects the position of the microplate stage and increases the robustness of the system, by performing routine auto-calibrations. This can reduce the downtime of the system since no specially-trained technician is required to teach the handover position.

[0024] FIG. 2 depicts a perspective view of a microplate gripper 120 for use in a microplate processing system. The gripper 120 includes two forks 122a, 122b, each of which include an arm 126 and a plurality of tines 128 for lifting a microplate (not shown). Each tine 128 terminates at a hook 130 that may be placed under an edge of a microplate so as to lift and lower the microplate. The hooks 130 also allow for a larger contact surface for each tine 128, which is relevant to the calibration systems and methods described herein. The gripper 120 includes one or more motors 132 that may be used to move the forks 122a, 122b along any of three axes that are mutually orthogonal. Such a system having first direction, second direction, and third direction that are mutually orthogonal to one another is referred to herein with reference to x-, y-, and z-axes, and is indicated by the three-dimensional axis labels in FIG. 2.

[0025] The axes depicted in FIG. 2 is for reference only and reflect both positive and negative portions of each axis, as would be apparent to a person of ordinary skill in the art. Further, the use of the “+” symbol is for reference purposes only. For example, “+z” is depicted in the conventional upward orientation, but as used herein “+z” may be used in a downward direction if desirable. Thus, the forks 122a, 122b may move upward (along the +z direction or axis), downward (along the -z direction or axis), forward (along the +x direction or axis, and parallel to a long edge of a microplate stage 134), backward (along the -x direction or axis), and laterally (along the +y and -y direction or axis, and parallel to a short edge of the stage 134.

[0026] It should be understood that Cartesian coordinate movement systems are just one system for driving a gripper relative to a microplate. In alternative embodiments, for example, there could be a sample loader that operates along cylindrical or spherical coordinate systems, or any other arbitrary movement directions. These directions can be based on the geometry of the sample loading area (see FIGS. 1 A and IB) or it can be based upon space constraints on the motor to move samples throughout the system, among other constraints or criteria. While Cartesian coordinates are used in many of the examples herein, it should be understood that the concepts described herein could apply equally to any other set of directional or ordinate systems.

[0027] In the context of the system 100 of FIGS. 1A and IB, the microplate stage 134 moves vertically within the elevator 104. As the dimensions of the forks 122a, 122b (and portions thereof) are known, along with the dimensions of the stage 134, contact between the arms 126 (in examples, more specifically, the tines 128 and / or hooks 130) and the stage 134 (and portions thereof) allows the system to known the position of the gripper 120 relative to the stage 134 and therefore a microplate that will be positioned thereon. The motor(s) 132 may include one or more encoders or other sensors that may be used to detect various positions of the various elements, as described in more detail herein. The gripper 120 may be secured to an imaging subsystem via a gantry 136. Further, the microplate gripper 120 may be configured to move the forks 122a, 122b simultaneously or individually, although simultaneously may provide more simple operability. Further, since the forks 122a, 122b are configured to move in opposing lateral directions (so as to grip and release a microplate), the forks 122a, 122b may move simultaneously along opposite +y and -y directions or axes.

[0028] The stage 134 is of known dimensions and includes a number of structural features that may be contacted by the tines 128 and / or hooks 130. The stage 134 includes an upper surface 138, end side surfaces 140, and lateral side surfaces 142. Since the side surfaces 140, 142 are portions of walls that surround the upper surface 138, the walls also have upper surfaces, outer surfaces, lower surfaces (on an underside of the stage 134, e.g.) that may be used as the required reference features for contact with the tines 128 and / or hooks 130. These walls can take the form of solid walls, such as those shown making up the lateral side surfaces 142. Alternatively, the walls can be broken up into smaller components such as a plurality of fingers 144 that prevent a microplate disposed on the stage 134 from moving forward, rearward, or laterally. In the embodiment shown in FIG. 2, the end side surfaces 140 are defined by such fingers 144. Because the various dimensions of the stage 134 are known, the calibration system described herein can detect a position of the microplate gripper 120 relative thereto and adjust subsequent movements thereof accordingly.

[0029] FIGS. 3A and 3B depict a schematic view of a calibration system 200 for a microplate gripper 120 in a first condition and in a second condition, respectively. As described above, each fork 122 includes an arm 126 and a plurality of tines 128 that each terminate at a hook 130. The gripper 120 is used to lift and lower a microplate (not shown) to or from a stage 134. One or more motor(s) 132 drives the position of the microplate gripper 120, as described with respect to FIG. 2.

[0030] FIG. 3A shows a calibration system 200. The calibration system 200 may include a detection circuit 202 that is used to detect contact between the microplate gripper 120 and the stage 134. In examples, the fork 122 is manufactured of a conductive material such as cooper, iron, zinc, aluminum, platinum, etc. The stage 134 may also be manufactured of similar or different conductive materials. In examples, conductive plastics may be utilized. In other examples, the fork 122 may be manufactured of non-conducive material, but may include one or more conductive wires and conductive contacts disposed, for example, on the tines 128 and / or hooks 130.

[0031] In a simple circuit example, a voltage V is applied to the calibration system 200 across a resistor R. As such, the conductive portions of the microplate gripper 120, such as the fork 122, are maintained at positive voltage compared to the stage 134, which is shown as being at ground voltage. As such, amplifier A will continue to provide power to motor control 135 as a sensor input. Amplifier A will continue to provide a sensor input to the motor control 135 as long as the fork 122 is not in contact with the stage 134. Once the fork contacts the stage 134, such as at the tines 128 or hooks 130, the voltage of the conductive portions of the microplate gripper 120 will be substantially zero (depending on the resistivity of the materials that make up the microplate gripper and the size of the resistor R). Amplifier A can have a threshold voltage such that electrical contact between the fork 122, tines 128, or hooks 130 of the microplate gripper with the stage 134 will eliminate the output signal from amplifier A. Accordingly, motor control 135 will be apprised based on lack of signal from amplifier A that there is contact between those components.

[0032] The detection circuit 202 detects a drop in current at the amplifier A due to the flow of current between the microplate gripper 120 and ground via the stage 134 when the stage 134 is in contact with the microplate gripper 120 as depicted schematically in FIG. 3B. When in the non-contacting position of FIG. 3A, a high input voltage to the operational amplifier A is detected, at approximately voltage V.

[0033] While a single detection circuit 202 is depicted for single one of the two forks 122, the detection circuit 202 may be connected to both forks 122 so as to detect contact between the stage 134 and either fork 122a, 122b.

[0034] In another example, a dedicated detection circuit 202 may be wired to a single discrete contact on one or both of the forks 122a, 122b. For example, a discrete contact may be disposed on a front of a forward tine 128 so as to detect contact when moving in the +x direction and that contact may be connected to a discrete detection circuit. Another discrete contact may be disposed on a side of a tine 128 so as to detect contact when moving in the +y or -y direction and that contact may be connected to a different discrete detection circuit. Still another discrete contact may be disposed on a bottom of a hook 130 so as to detect contact when moving in the -z direction and that contact may be connected to a yet another discrete detection circuit. With multiple detection circuits, contact between discrete portions of the forks 122 and the stage 134 may be detected. It should be understood that in alternative embodiments, the system could be reversed. That is, the microplate could be maintained at a voltage and the gripper could be connected to ground via a resistor or other source of impedance. When the microplate and the gripper come into contact, in that version, the voltage on the gripper will increase rather than dropping to ground. Such a voltage chance can be read by a controller to record the position where the gripper bumps against the microplate. In fact, in some embodiments neither the microplate nor the gripper is kept at ground. There could be, for example, a voltage supply that drives a current when a circuit is closed by the contact of the gripper with the microplate. In such embodiments, an ammeter or voltmeter can be used, depending on the specifics of the circuitry, to determine when the circuit is closed and thereby determine the boundary of the microplate.

[0035] Such a configuration is not required, however. Indeed, a single detection circuit 202 is sufficient for detecting contact between a fork 122 and the stage 134, as the calibration system 200 monitors a direction of movement of the microplate gripper 120 until contact is detected. That is, if the microplate gripper 120 is moving in the +x direction, detection of a current with the detection circuit 202 indicates that a portion of the stage 134 within that +x direction path of travel has been contacted. This condition is the same for other directions of travel as well. As such, the calibration system 200 can determine the portion of the stage 134 contacted, based on the direction of travel of the microplate gripper 120 prior to contact being made. Contact between the microplate gripper 120 and the stage 134 may be detected in other ways. For example, the load on the motor 132 may be monitored. An increase in load in the form of a current draw by the motor 132 in excess of a threshold may also indicate contact. This may be a less desirable approach, however, since excess load on the motor may be indicative of a mechanical problem, such as a jammed mechanism, blocked imaging subsystem housing exit, or other issue unrelated to positioning. Other methods to detect contact are also contemplated.

[0036] FIGS. 4A-4G depict a method of calibrating a position of a microplate gripper 120 relative to a microplate stage 134. Reference numerals used in FIGS. 4A-4G are consistent with those used in FIG. 2, although the motor(s) 132 and gantry 136 have been removed for clarity. Some components are simplified, such as the side surfaces 140, 142, which are shown as substantially planar walls rather than incorporating fingers 144 as depicted in FIG. 2.

[0037] The method of FIGS. 4A-4G may begin with the microplate gripper 120 extending from a housing, such as an imaging subsystem housing, incubator housing, or other housing. Additionally, the forks 122a, 122b may be brought to an initial close separation distance from each other, as depicted, which may be desirable to reduce the possibility of the hooks 130 contacting the upper portions of the walls that form the side surfaces 140, 142 during deployment. Bringing the forks 122a, 122b within closer proximity may help ensure contact with the upper surface 138 of the stage 130 at the start of the method. This separation distance may be set at the beginning of the method (prior to any movement of the microplate gripper along any of the z-axis, the x-axis, and the y-axis) or before a movement of the microplate gripper 120 along at least one of the z-axis, the x-axis, and the y-axis. In examples, the separation distance may be less than a known dimension of the stage 134, for example, a smallest known dimension of the upper surface 138 thereof, to increase the likelihood of contact.

[0038] Microplate gripper 120 is moved as shown by the arrow in FIG. 4A in the +x direction parallel to the stage 134 and out of the housing (not shown) from which the gripper 120 operates and is supported. The gripper 120 is positioned generally above an expected position of the microplate stage 134. In FIG. 4B, the microplate gripper 120 moves along a -z axis in a direction towards the stage 134, due to activation of the motor 132. Upon contact of the tine 128 or hook 130 with the upper surface 138 of the stage 134, the detection circuit (not shown) detects a voltage change indicative of contact.

[0039] Upon detection of contact, delivery of operating current to the motor 132 is terminated and further movement along the -z axis ends. Thereafter, as depicted in FIG. 4C, the forks 122a, 122b may be retracted (e.g., moved along the +z axis) slightly to eliminate contact. This enables further movement of the forks 122a, 122b without dragging the hooks 130 along the upper surface 138 of the stage 134. In FIG. 4D, the microplate gripper 120 moving along a +x axis in a direction towards an end side surface 140, again due to activation of the motor 132. Upon contact of the tine 128 or hook 130 with the end side surface 140 of the stage 134, the detection circuit (not shown) detects a current flow indicative of contact. Upon detection of contact, delivery of voltage to the motor 132 is terminated and further movement along the +x axis ends.

[0040] Thereafter, as depicted in FIG. 4E, the forks 122a, 122b may be retracted (e.g., moved along the -x axis) to eliminate contact. In examples, the microplate gripper 120 may be returned to a starting point proximate the presumed center of the stage 134, or the retraction along the -x axis may be slight. This enables further movement of the forks 122a, 122b without dragging the tines 128 or hooks 130 along the end side surface 140 of the stage 134.

[0041] In FIG. 4F, the microplate gripper 120 is moved along a +y axis in a direction towards a lateral side surface 142 of the stage 134, due to activation of the motor 132. Upon contact of the tine 128 or hook 130 with the lateral side surface 142 of the stage 134, the detection circuit (not shown) detects a current flow indicative of contact. Upon detection of contact, delivery of operating current to the motor 132 is terminated and further movement along the -y axis ends. Thereafter, as depicted in FIG. 4G, the forks 122a, 122b may be retracted (e.g., moved along the -y axis) to eliminate contact. This enables further movement of the forks 122a, 122b.

[0042] The various signals may be recorded and / or processed during the calibration sequence as they occur, or all signals may be processed after a plurality of signals are received. Regardless, with the required signals processed, the position of the microplate gripper 120 relative to the stage 134 is known. Processing the detected signals may include comparing the position of the microplate gripper 120 at the time of signal detection to a known dataset. The dataset may include dimensional data of the microplate stage. Such dimensional data may include dimensions of the stage 134 (e.g., height, length, width, thickness, etc.), dimensional data of components of the stage 134 (e.g., a thickness of a wall that defines side surfaces 140, 142, etc.), dimensional data of the microplate gripper 120 (e.g., tine number and length, initial separation distance of the forks 122a, 122b, etc.), anticipated starting position of the microplate gripper 120 or components thereof at the start of the calibration method, etc. Further movements of the microplate gripper 120, e.g., to lift and lower a microplate, may then be adjusted based on the determined position of the stage 134.

[0043] FIG. 5 depicts another method 300 of calibrating a position of a microplate gripper. The method 300 differs from the method depicted above in FIGS. 4A-4G at least in that it is agnostic to particular movement directions and is not limited to movement of a gripper. In other words, to the extent a stage is configured for movement relative to a fixed gripper, the method 300 of FIG. 5 enables such functionality. The method 300 begins with operation 302, contacting a first surface of the microplate stage with the gripper. Upon contact, a contact signal indicating contact between the gripper and the microplate stage is received at a processor, operation 304a. Upon receipt, operation 304b, recording a position of the gripper at the receipt of the signal, is performed. This recorded position is then compared to a dimensional data of the microplate gripper and the microplate stage, operation 304c. This dimensional data may include relevant dimensions of the microplate stage, such as, stage dimensions such as height, width, and depth; similar outer dimensions; dimensions regarding the width or thickness of walls of the stage; predicted elevation of the stage; etc. This dimensional data may also include relevant dimensions of the gripper, such as, length, height, or width of the grippers or components thereof, such as the arms or the tines; number of tines; initial spacing, maximum spacing, or minimum spacing between the arms; number and spacing of tines; the distance from which the gripper may extend from the housing in which it is supported; dimensions of the housing opening; etc. In general, any dimension or information relevant to determining a position of the gripper relative to the microplate stage may be considered dimensional data.

[0044] Thereafter, operation 306, contacting a second surface of the microplate stage with the gripper, is performed. In examples, the second surface is a surface substantially orthogonal or otherwise at an angle to the first surface. However, in other examples, the second surface may be disposed parallel to the first surface. Such functionality may be particularly valuable if, for example, the known dimensional data of the microplate is incomplete. In another example, contacting first and second parallel surfaces may be advantageous if the first comparison at operation 304c indicates a surface being in a position outside of an expected threshold, which might indicate the stage being incorrectly positioned on its support structure. Regardless, upon contact, with the second surface, operations 308a, 308b, and 308c are performed. Those operations correspond generally to operations 304a, 304b, and 304c, respectively.

[0045] Thereafter, operation 310, contacting a third surface of the microplate stage with the gripper, is performed. The third surface may be parallel or orthogonal to either or both of the first or second surfaces, for reasons explained above. Upon contact with the third surface, operations 312a, 312b, and 312c are performed. Those operations correspond generally to operations 304a, 304b, and 304c, respectively.

[0046] FIG. 6 depicts a block diagram of a computing device, according to various aspects. In the illustrated example, the computing device 400 may include a bus 402 or other communication mechanism of similar function for communicating information, and at least one processing element 404 (collectively referred to as processing element 404) coupled with bus 402 for processing information. As will be appreciated by those skilled in the art, the processing element 404 may include a plurality of processing elements or cores, which may be packaged as a single processor or in a distributed arrangement. Furthermore, a plurality of virtual processing elements 404 may be included in the computing device 400 to provide the control or management operations for the gripper movement and signal detection operations described above, but especially in FIGS. 3A-4G, as well as the contact detection methods depicted in FIGS. 4A-4G and 5, illustrated above.

[0047] The computing device 400 may also include one or more volatile memory(ies) 406, which can for example include random access memory(ies) (RAM) or other dynamic memory component(s), coupled to one or more buses 402 for use by the at least one processing element 404. Computing device 400 may further include static, non-volatile memory(ies) 408, such as read only memory (ROM) or other static memory components, coupled to buses 402 for storing information and instructions for use by the at least one processing element 404. A storage component 410, such as a storage disk or storage memory, may be provided for storing information and instructions for use by the at least one processing element 404. As will be appreciated, the computing device 400 may include a distributed storage component 412, such as a networked disk or other storage resource available to the computing device 400.

[0048] The computing device 400 may be coupled to one or more displays 414 for displaying information to a user. Optional user input device(s) 416, such as a keyboard and / or touchscreen, may be coupled to bus 402 for communicating information and command selections to the at least one processing element 404. An optional cursor control or graphical input device 418, such as a mouse, a trackball or cursor direction keys for communicating graphical user interface information and command selections to the at least one processing element. The computing device 400 may further include an input / output (I / O) component, such as a serial connection, digital connection, network connection, or other input / output component for allowing intercommunication with other computing components and the various components of the systems depicted in FIGS. 1A-3B, as well as the methods depicted in FIGS. 4A-5, illustrated above.

[0049] In various embodiments, computing device 400 can be connected to one or more other computer systems via a network to form a networked system. Such networks can for example include one or more private networks or public networks, such as the Internet. In the networked system, one or more computer systems can store and serve the data to other computer systems. The one or more computer systems that store and serve the data can be referred to as servers or the cloud in a cloud computing scenario. The one or more computer systems can include one or more web servers, for example. The other computer systems that send and receive data to and from the servers or the cloud can be referred to as client or cloud devices, for example. Various operations of the systems depicted in FIGS. 1A-3B, as well as the methods depicted in FIGS. 4A-5, illustrated above may be supported by operation of the distributed computing systems.

[0050] The computing device 400 may be operative to control operation of the components of the microplate gripper 120 or carry out the methods described with respect to FIGS. 4 A— 4G and 5. Such control can be accomplished via a communication device such as, e.g., communication device 420, and to handle data provided from the data sources as discussed above. In some examples, analysis results are provided by the computing device 400 in response to the at least one processing element 404 executing instructions contained in memory 406 or 408 and performing operations on the received data items. Execution of instructions contained in memory 406 and / or 408 by the at least one processing element 404 can render the systems depicted in FIGS. 1A-3B, as well as the methods depicted in FIGS. 4A-5, operative to perform methods described herein.

[0051] The term "computer-readable medium" as used herein refers to any media that participates in providing instructions to the processing element 404 for execution. Such a medium may take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media includes, for example, optical or magnetic disks, such as disk storage 410. Volatile media includes dynamic memory, such as memory 406. Transmission media includes coaxial cables, copper wire, and fiber optics, including the wires that include bus 402.

[0052] Common forms of computer-readable media or computer program products include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, or any other magnetic medium, a CD-ROM, digital video disc (DVD), a Blu-ray Disc, any other optical medium, a thumb drive, a memory card, a RAM, PROM, and EPROM, a FLASH-EPROM, any other memory chip or cartridge, or any other tangible medium from which a computer can read.

[0053] Various forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to the processing element 404 for execution. For example, the instructions may initially be carried on the magnetic disk of a remote computer. The remote computer can load the instructions into its dynamic memory and send the instructions over a telephone line using a modem. A modem local to computing device 400 can receive the data on the telephone line and use an infra-red transmitter to convert the data to an infra-red signal. An infra-red detector coupled to bus 402 can receive the data carried in the infra-red signal and place the data on bus 402. Bus 402 carries the data to memory 406, from which the processing element 404 retrieves and executes the instructions. The instructions received by memory 406 and / or memory 408 may optionally be stored on storage device 410 either before or after execution by the processing element 404.

[0054] In accordance with various embodiments, instructions operative to be executed by a processing element to perform a method are stored on a computer- readable medium. The computer readable medium can be a device that stores digital information. For example, a computer-readable medium includes a compact disc readonly memory (CD-ROM) as is known in the art for storing software. The computer- readable medium is accessed by a processor suitable for executing instructions configured to be executed.

[0055] It is to be understood that this disclosure is not limited to the particular structures, process steps, or materials disclosed herein, but is extended to equivalents thereof as would be recognized by those ordinarily skilled in the relevant arts. It should also be understood that terminology employed herein is used for the purpose of describing particular examples only and is not intended to be limiting. It must be noted that, as used in this specification, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

[0056] It will be clear that the systems and methods described herein are well adapted to attain the ends and advantages mentioned as well as those inherent therein. Those skilled in the art will recognize that the methods and systems within this specification may be implemented in many manners and as such is not to be limited by the foregoing exemplified examples and examples. In this regard, any number of the features of the different examples described herein may be combined into one single example and alternate examples having fewer than or more than all of the features herein described are possible.

[0057] While various examples have been described for purposes of this disclosure, various changes and modifications may be made which are well within the scope contemplated by the present disclosure. Numerous other changes may be made which will readily suggest themselves to those skilled in the art and which are encompassed in the spirit of the disclosure.

Claims

CLAIMSWhat is claimed is:

1. A method of calibrating a microplate gripper comprising a fork comprising at least one tine, the method comprising: moving the tine along a first direction to contact a first surface of a microplate stage with the tine; moving the tine along a second direction to contact a second surface of the microplate stage with the tine; moving the tine along a third direction so as to contact a third surface of the microplate stage with the tine; detecting a signal at each contact between the tine and the microplate stage at the first, second, and third surfaces; and recording a position of the tine at the detection of each of the signals.

2. The method of claim 1, wherein each of the detected signals comprise a voltage drop at an electrical node coupled to a controller of a motor configured to move the tine relative to the microplate stage in the first, second, and third directions.

3. The method of claim 2, wherein each of the detected signals comprise a motor current draw in excess of a threshold.

4. The method of any of claims 2-3, further comprising actuating the motor for each moving of the tine.

5. The method of claim 4, further comprising terminating a voltage delivery to the motor at the detection of each signal.

6. The method of any of claims 1-5, further comprising retracting the tine along the first direction to terminate contact between the first surface of the microplate and the tine.

7. The method of claim 6, further comprising retracting the tine along the second direction to terminate contact between the second surface of the microplate and the tine.

8. The method of any of claims 6-7, further comprising retracting the tine along the third direction to terminate contact between the third surface of the microplate and the tine.

9. The method of any of claims 1-8, wherein the tine comprises a plurality of tines.

10. The method of any of claims 1-9, wherein the fork comprises a plurality of forks.

11. The method of any of claims 1-10, further comprising comparing the recorded position of the tine at each of the detected signals to a known dataset.

12. The method of claim 11, wherein the known dataset comprises a dimensional data of the microplate stage.

13. The method of any of claims 11-12, wherein the known dataset comprises a dimensional data of at least one of the fork and the tine.

14. The method of any of claims 11-13, wherein the known dataset comprises a dimensional data of a known microplate.

15. The method of any of claims 11-14, further comprising adjusting a microplate gripper datum based at least in part on the comparison.

16. The method of any of claims 1-15, wherein the microplate gripper comprises a plurality of forks and wherein the method further comprises setting a separation distance between the plurality of forks.

17. The method of claim 16, wherein setting the separation distance is performed prior to moving the tine along any of the first direction, the second direction, and the third direction.

18. The method of any of claims 16-17, wherein the first direction, the second direction, and the third direction are all mutually orthogonal one another.

19. The method any of claims 16-18, wherein the separation distance is less than a known dimension of the microplate stage.

20. The method of claim 19, wherein the known dimension comprises a smallest dimension of the upper surface of the microplate.

21. A method of calibrating a position of a microplate gripper relative to a microplate stage, the method comprising: contacting a first surface of the microplate stage with the gripper; contacting a second surface of the microplate stage with the gripper; contacting a third surface of the microplate stage with the gripper, wherein each of the first surface, the second surface, and the third surface are disposed substantially orthogonal to each other; receiving an electrical signal at each contact between the gripper and the microplate stage when contacting each of the first surface, the second surface, and the third surface; recording a position of the gripper at the receipt of each of the signals; and comparing each of the positions to a dimensional data of the microplate gripper and the microplate stage.

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