A specimen transport system may be used to convey specimens within a laboratory analysis system. Specimens may be samples of blood or other bodily fluids on which laboratory analysis is to be performed. Preparation of a sample for analysis may require transporting the sample to various stations for aliquotting, centrifuging, or other processes. The sample may then be transported to a location where analysis is to be performed and to an output station for storage or disposal. Various transportation systems may be used to transport samples between stations of a laboratory analysis system.
A conveyor transport system may use a conveyor belt or conveyor track to transport sample tubes between stations. Typically, a sample tube is inserted into a sample carrier that holds the specimen in a fixed upright position for transport by the conveyor system. The sample carrier may be configured to receive one or more sample tubes.
A sample tube may require centrifuging prior to analysis. Sample tubes may be inserted into a centrifuge adapter for centrifuging. One or more centrifuge adapters may be placed in the centrifuge. When sample tubes or centrifuge adapters having varying weights are loaded into a centrifuge, the centrifuge may wobble due to imbalance.
Centrifuges may use imbalance sensors to determine when a centrifuge is experiencing imbalance. Centrifuges typically have some tolerance for imbalance. However, if imbalance occurs in excess of a centrifuge's imbalance tolerance, samples may be damaged or destroyed. An imbalance sensor may be used to discontinue the spinning of a centrifuge rotor in the case that the imbalance of a centrifuge exceeds the centrifuge's imbalance tolerance.
Conventional centrifuge imbalance sensors use contact switch based imbalance sensing or optical switch based imbalance sensing to determine when sample volume imbalance exceeds a centrifuge's imbalance tolerance. In contact switch based imbalance sensing, imbalance is indicated when a containment vessel of a centrifuge contacts a contact switch. Contact switches must be mechanically adjusted for the tolerance of a particular centrifuge and may be damaged by impact with the containment vessel in the case of large imbalances. In optical switch based imbalance sensing, a flag attached to a containment vessel breaks an optical beam. Contaminants interrupting the beam can interfere with the functionality of optical switch imbalance sensing. Existing contact switch and optical switch based imbalance sensors are limited to sensing displacement of a containment vessel in one dimension.
Embodiments of the invention solve these and other problems.
Embodiments of the technology relate to systems and methods for efficiently processing samples collected for laboratory analysis. More specifically, a system and method for obtaining information about specimen containers using fixed sensors are described. A system and method for sensing centrifuge imbalance are also described.
One embodiment is directed to a system for non-contact specimen container characterization. The system for non-contact specimen container characterization includes a processor and a specimen container diameter sensor and a specimen container length sensor communicatively coupled to the processor. The specimen container diameter sensor includes a horizontally oriented linear optical array. The specimen container length sensor includes a vertically oriented linear optical array. The specimen container diameter sensor and the specimen container length sensor are located in a fixed position relative to a conveyor for transporting a plurality of specimen containers.
In some embodiments, the non-contact specimen container characterization further includes a cap color sensor that is communicatively coupled to the processor. The cap color detector includes a light to frequency converter.
Another embodiment is directed to a method for non-contact specimen characterization. The method includes receiving a first signal from a specimen container diameter sensor at a processor. A second signal is received by the processor form a specimen container length sensor. A specimen container diameter is determined based on the first signal and a specimen container length is determined based on the second signal.
A further embodiment is directed to an imbalance sensor for detecting centrifuge imbalance. The imbalance sensor includes an accelerometer that is coupled to a centrifuge containment vessel. A comparator is configured to compare an accelerometer output with a reference voltage level. A switch receives an output form the comparator. The rotation of the centrifuge is discontinued based on the output of the switch.
An additional embodiment is directed to an imbalance sensor for detecting centrifuge imbalance along multiple axes. The imbalance sensor includes an accelerometer that is coupled to a centrifuge containment vessel. A first comparator is configured to compare an accelerometer output corresponding to a first axis with a first voltage level. A second comparator is configured to compare an accelerometer output corresponding to a second axis with a second voltage level.
Another embodiment is directed to a method for detecting centrifuge imbalance along multiple axes. The method includes coupling an accelerometer to a centrifuge containment vessel. A first comparator compares an accelerometer output corresponding to a first axis with a first voltage level. A second comparator compares an accelerometer output corresponding to a second axis with a second voltage level. A third comparator compares an accelerometer output corresponding to a third axis with a third voltage level. A summing comparator compares a sum of the outputs from the first comparator, the second comparator and the third comparator to a fourth voltage level. If the sum of the outputs exceed the fourth voltage level, the rotation of a centrifuge is discontinued
These and other embodiments of the technology are described in further detail below.
A further understanding of the nature and advantages of the different embodiments may be realized by reference to the following drawings.
a)-4(c) show illustrative side views of the specimen container sensors of a non-contact specimen container characterization system.
An automated system for processing specimens for laboratory analysis may include a conveyance device to transport the specimens between laboratory modules. For example, a specimen may require aliquotting and/or centrifuging before the specimen is analyzed. It may be beneficial to determine one or more physical characteristics of a specimen container with a sensor system that is in a fixed position relative to the specimen container. For example, the sensor system may be installed in a fixed position relative to a system for transporting specimen containers, such as a conveyor belt.
When specimens are loaded into a centrifuge, imbalance may occur during the centrifuge process due to varying weights of the specimen containers in the centrifuge. If the centrifuge exceeds the imbalance tolerance of the centrifuge, it may be desirable to halt the centrifuge process. An accelerometer based imbalance sensor can be used to sense imbalance along multiple axes.
Embodiments of a non-contact specimen container characterization system and accelerometer based centrifuge imbalance sensor are discussed in more detail below.
Physical characteristics of a specimen container may be determined using one or more sensors that are fixed relative to a specimen transport system. For example, it may be desirable to determine physical characteristics of a specimen container as the specimen container is transported between stations of a laboratory analysis system. A non-contact specimen container characterization system may be capable of determining various physical characteristics of a specimen container with no contact between the sensor devices and the specimen container. In comparison with a specimen container characterization system that picks up a specimen or otherwise requires contact with the specimen container to determine characteristics of the specimen container, a non-contact specimen container characterization system may obtain information about the specimen container in a relatively time-efficient manner, allowing for rapid specimen processing. Additionally, non-contact specimen container characterization system can determine characteristics of a specimen container without disturbing the position of the container. This may be beneficial for systems in which position of specimen containers in a queue is related to the order in which specimen containers are scheduled to be processed.
Physical characteristics such as specimen container diameter and specimen container length may be determined by the non-contact specimen container characterization system. The color of a cap for a specimen container may also be determined. In some embodiments, liquid level determinations may be performed by a non-contact specimen characterization system.
A specimen container may be transported by a transport system such as a conveyor transport system, a self-propelled puck transport system, a magnetic transport system, or other transport system. A conveyor transport system may include a conveyor, such as a conveyor belt or track, for transporting specimens.
The specimen container may be a sample tube used to contain samples of blood or other fluids for laboratory analysis. One or more specimen containers may be inserted into a sample carrier for transport by a conveyor transport system or other transport system. For example, a sample carrier placed on a conveyor belt may be carried by the movement of the belt.
In some embodiments, sensors 206, 208 and 210 are able to determine physical characteristics associated with the specimen container 202 as the specimen container 202 is moved by the conveyor belt 204. In alternative embodiments, conveyor belt 204 is configured to stop when sample tube 212 is at a position at which sensors 206, 208 and 210 are able to determine physical characteristics of sample tube 202.
a)-4(c) show illustrative side views of the specimen container sensors depicted in
b) shows specimen container cap color sensor 208. Specimen container cap color sensor 208 may comprise one or more color sensors for determining a color of a cap on specimen container 212. The color sensor is configured to sense an area aligned with the cap of specimen container 212. Multiple cap color sensors 220, 222 and 224 are illustrated by the dotted lines in
c) shows a specimen container length sensor 210. The length sensor 210 can have a light detector that is vertically oriented (as indicated by the dotted line originating at length sensor 210). For example, the light detector of length sensor 210 can be a linear optical array (e.g., a TAOS TSL3301-LP linear array) having a plurality of photodiodes (i.e., pixels) arranged in a linear array similar to the linear optical array described with reference to diameter sensor 206. The length of specimen container 212 (e.g., from the bottom of the tube to the top of the cap) can be determined based on the output of the linear optical array of length sensor 210. In some embodiments, length sensor 210 may be used to detect the liquid level of one or more liquid types in specimen container 212.
In some embodiments, a sensor is used to determine whether specimen container 212 is in a position at which physical characteristics of specimen container 212 can be determined. For example, the output of specimen container length sensor 210 may be used to determine whether specimen container 212 is in a position at which cap color sensor 208 can determine the cap color of specimen container 212.
In various embodiments, a conveyor system controller 536 may be communicatively coupled to processor 508. Conveyor system controller 536 may be a processor that generates signals to drive a conveyor motor, such as a conveyor motor associated with a conveyor belt 510. Alternatively, conveyor system controller 536 may be a motor associated with a conveyor belt 510. Processor 508 may receive a signal from one or more of diameter sensor 502, length sensor 504, and/or cap color sensors 506, 530, 532 and processor 508 may execute instructions to determine when a specimen container 212 is in a position at which its physical characteristics can be determined, based on the received signal or signals. When the specimen container 212 is in a position at which its physical characteristics can be determined, the processor 508 may generate a signal instructing conveyor system controller 536 to halt the motion of the conveyor. In this manner, a conveyor belt is stopped each time a specimen container 212 is aligned with the characterization sensors.
Instructions executed by the processor 508 may be stored on processor 508 or may be stored in a memory 534 accessible by processor 508.
At operation 608, processor 508 receives a second signal from specimen container length sensor 504. Based on the second signal, processor 508 can determine the length of the specimen container 212, as indicated at operation 610. At operation 612, processor 508 can determine which of cap color sensors 506, 530, 532 to use for determining the color of cap 226. At operation 614, processor 508 receives a third signal from the cap color sensor determined at operation 612. Based on the signal from the cap color sensor determined at operation 612, processor 508 can determine the cap color of cap 226.
In some embodiments, processor 508 may receive a signal from diameter sensor 502 after the conveyor has been halted. Based on the signal received from diameter sensor 502, processor 508 can determine the diameter of specimen container 212.
After the physical characteristics of a specimen container have been determined, the specimen container may proceed to a centrifuge module for centrifugation. The physical characteristics of the specimen container can be performed after centrifugation.
A centrifuge may include an imbalance sensor to prevent excessive imbalance of the centrifuge. An accelerometer based imbalance sensor may be used to determine when centrifuge imbalance is occurring in excess of the imbalance tolerance of a centrifuge.
The accelerometer based imbalance sensor may sense acceleration of a centrifuge containment vessel along one, two, or three axes. Sensing along three axes may provide a level of detail about the imbalance occurring in a centrifuge to allow monitoring for early wear of shock mounting structures or other mechanical components of a centrifuge. Determining imbalance based on acceleration (i.e. “g force”) may provide a more accurate indication than is available from displacement based sensing techniques.
An illustrative system diagram of an accelerometer based centrifuge imbalance sensor is depicted in
Accelerometer 708 may be a single- or multi-axis device capable of generating a signal corresponding to the acceleration of an object to which the accelerometer is mechanically coupled. The accelerometer may have piezoelectric, piezoresistive, capacitive or other component capable of generating a signal based on acceleration. Accelerometer 708 may be a micro electro-mechanical systems (MEMS) device, such as the LIS3L02AS4 3-axis solid state linear accelerometer by STMicroelectronics.
Accelerometer 708 may output voltage values corresponding to the acceleration of centrifuge containment vessel 704 along three axes, e.g., x-, y- and z-axes. The x-axis output voltage of accelerometer 708 may be compared to a first reference voltage at x-axis comparator 710. The y-axis output voltage of accelerometer 708 may be compared to a second reference voltage at y-axis comparator 712. The z-axis output voltage of accelerometer 708 may be compared to a third reference voltage at z-axis comparator 714. The voltage output of comparators 710, 712, and 714 may be added to obtain a sum voltage. Summing comparator 716 may compare the sum voltage to a fourth reference voltage. One or more of the first reference voltage, second reference voltage, third reference voltage and fourth reference voltage can be based on the imbalance tolerance of the centrifuge and may be adjustable. For example, a potentiometer may be adjusted to alter a supply voltage, or a value may be adjusted in software or firmware associated with imbalance sensor 706. The adjustable reference voltage values may allow the imbalance sensor to be adjusted for use with different centrifuges having different imbalance tolerances.
The output of summing comparator 716 may be provided to switch 718. Switch 718 may be, e.g., a field-effect transistor (FET) switch. The output of the switch may be connected to centrifuge 702 such that rotation of centrifuge 702 is discontinued when the state of switch 718 corresponds to an imbalance condition of the centrifuge as indicated by the output of summing comparator 716. In this manner, when acceleration of centrifuge containment vessel 704 as measured along one or more of the x-axis, y-axis and z-axis exceeds the imbalance tolerance threshold of centrifuge 702, rotation of centrifuge 702 can be discontinued. In some embodiments, an alert may be generated based on the output of comparator 710, comparator 712, comparator 714, comparator 716, and/or switch 718. The alert may be a message, light, sound, etc., that may be communicated to a laboratory automation system and/or displayed or emitted by the centrifuge.
One or more of comparators 710, 712, 714, and 716 may be communicatively coupled to a processor. The processor (not shown) may be a processor associated with centrifuge 702, a processor of a laboratory automation system, or a processor of another system or computer. Instructions executed by the processor may be stored on the processor or may be stored in a memory (not shown) accessible by the processor. Switch 718 may be communicatively coupled to a processor. An alert may be generated when the output of one or more of comparators 710, 712, 714, and 716 exceeds a threshold voltage level. In another embodiment, an alert may be generated when a switch 718 is switched to a state resulting in centrifuge 702 shutdown. Such alerts may be transmitted to a laboratory automation system computer such that scheduling of sample processing can be adjusted based on the centrifuge shutdown.
In some embodiments, one or more components of imbalance sensor 706, such as accelerometer 708, comparators 710-716, switch 718, and other associated components, may be mounted on a PCB. The PCB may be mounted to centrifuge containment vessel 704 such that the acceleration of centrifuge containment vessel 704 is transmitted to accelerometer 708.
In some embodiments, the resistors used to regulate one or more of the first reference voltage, second reference voltage, third reference voltage and fourth reference voltage are replaced with a digital to analog converter that allows setting of reference voltage values with software via a user interface. In this manner, the accelerometer based imbalance sensor is easily adaptable to various centrifuges having different imbalance tolerance levels and to accommodate various sample handling requirements. Alternatively, the resistors used to regulate one or more of the first reference voltage, second reference voltage, third reference voltage and fourth reference voltage are replaced with potentiometers to allow manual adjustment of the resistance values.
The various participants and elements described herein with reference to the figures may operate one or more computer apparatuses to facilitate the functions described herein. Any of the elements in the above description, including any servers, processors, or databases, may use any suitable number of subsystems to facilitate the functions described herein, such as, e.g., functions for operating and/or controlling the functional units and modules of the laboratory automation system, transportation systems, the scheduler, the central controller, local controllers, etc.
Examples of such subsystems or components are shown in
Embodiments of the technology are not limited to the above-described embodiments. Specific details regarding some of the above-described aspects are provided above. The specific details of the specific aspects may be combined in any suitable manner without departing from the spirit and scope of embodiments of the technology. For example, back end processing, data analysis, data collection, and other processes may all be combined in some embodiments of the technology. However, other embodiments of the technology may be directed to specific embodiments relating to each individual aspect, or specific combinations of these individual aspects.
It should be understood that the present technology as described above can be implemented in the form of control logic using computer software (stored in a tangible physical medium) in a modular or integrated manner. Furthermore, the present technology may be implemented in the form and/or combination of any image processing. Based on the disclosure and teachings provided herein, a person of ordinary skill in the art will know and appreciate other ways and/or methods to implement the present technology using hardware and a combination of hardware and software
Any of the software components or functions described in this application, may be implemented as software code to be executed by a processor using any suitable computer language such as, for example, Java, C++ or Perl using, for example, conventional or object-oriented techniques. The software code may be stored as a series of instructions, or commands on a computer readable medium, such as a random access memory (RAM), a read only memory (ROM), a magnetic medium such as a hard-drive or a floppy disk, or an optical medium such as a CD-ROM. Any such computer readable medium may reside on or within a single computational apparatus, and may be present on or within different computational apparatuses within a system or network.
The above description is illustrative and is not restrictive. Many variations of the technology will become apparent to those skilled in the art upon review of the disclosure. The scope of the technology should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the pending claims along with their full scope or equivalents.
One or more features from any embodiment may be combined with one or more features of any other embodiment without departing from the scope of the technology.
A recitation of “a”, “an” or “the” is intended to mean “one or more” unless specifically indicated to the contrary.
All patents, patent applications, publications, and descriptions mentioned above are herein incorporated by reference in their entirety for all purposes. None is admitted to be prior art.
This application claims priority to U.S. Provisional Patent Application No. 61/556,667, filed Nov. 7, 2011 and entitled “Analytical System and Method for Processing Samples,” herein incorporated by reference in its entirety for all purposes. This application also claims priority to U.S. Provisional Patent Application No. 61/616,994, filed Mar. 28, 2012 and entitled “Analytical System and Method for Processing Samples,” herein incorporated by reference in its entirety for all purposes. This application further claims priority to U.S. Provisional Patent Application No. 61/680,066, filed Aug. 6, 2012 and entitled “Analytical System and Method for Processing Samples,” herein incorporated by reference in its entirety for all purposes.
Number | Date | Country | |
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61556667 | Nov 2011 | US | |
61616994 | Mar 2012 | US | |
61680066 | Aug 2012 | US |