System and method for drum position detection

Abstract

A system (6000) and method (7000, 7050) for detecting the position of a rotating drum (6050) of a blood culture device relative to a stationary measurement board (6060) disposed adjacent to the rotating drum (6050). The system (6000) and method (7000, 7050) can adjust at least one stored signal of a sensor (6062) of the measurement board (6060) based on the detected position of the rotating drum (6050).

Description

Technical Field

[0001] Cross - Reference to Related Applications This application relates to PCT Application No. PCT / US2020 / 045065, filed on August 5, 2020, which is incorporated herein by reference. This application claims the priority and benefit of U.S. Provisional Patent Application No. 63 / 390,506, filed on July 19, 2022, which is incorporated herein by reference.

[0002] The present technology relates to a system and method for detecting the position (and its changes) of a rotating drum of a blood culture device relative to a stationary measurement board disposed adjacent to the rotating drum. The system and method of the present technology adjust at least one signal of a sensor of the measurement board based on the detected position of the rotating drum.

Background Art

[0003] The presence of biological agents such as bacteria in a patient's body fluid, particularly blood, is typically identified using blood culture bottles. A small amount of blood is injected through a sealed rubber septum into a sterile bottle containing a culture medium, and then the bottle is incubated at about 35°C while the growth of microorganisms is monitored.

[0004] Since it is of utmost importance to know whether a patient is infected with bacteria, hospitals and laboratories have automated devices that can process many blood culture bottles simultaneously. An example of such a device is the BD BACTEC™ system, manufactured and sold by Becton, Dickinson and Co. U.S. Patent No. 5,817,508 to Berndt et al. describes a prior art blood culture device and is incorporated herein by reference. Additional descriptions of the Blood Culture Apparatus are provided in U.S. Patent No. 5,516,692 (“Compact Blood Culture Apparatus”) and U.S. Patent No. 5,498,543 (“Sub-Compact Blood Culture Apparatus”), both of which are incorporated herein by reference.

[0005] Referring to FIG. 1, a mixture 22 of culture medium and a blood sample has been introduced into a sealed glass bottle 1, which contains photochemical sensing means 20 on their inner bottom surface 21. The photochemical sensing means 20 emits different amounts of light depending on the amount of gas in bottle 1. For example, the gas detected by the light sensing means 20 can be carbon dioxide, oxygen, or any gas that increases or decreases depending on the presence or absence of microbial growth within bottle 1.

[0006] As shown in FIGS. 1 and 2, a plurality of such bottles 1 are radially arranged on the bell-shaped rotary drum 2 in the incubator 5 with the bottom of the bottle 1 directed towards the drum shaft 28. The bell-shaped drum 2 is hollow and is supported by a shaft 24 whose one end is rotatably supported by two large ball bearings 3 and 4 mounted on the first side 51 of the equipment main frame 50. In order to read the information coming from each photochemical detection means 20 in the bottle 1, the linear array 12 of sensor stations is mounted inside the bell-shaped rotary drum 2 at a short distance from the inside of the bell-shaped drum 2 such that during the rotation of the drum 2, the individual bottles 1 pass through the respective sensor stations 15 of the array 12, on the second side 52 of the equipment main frame 50 within the bell-shaped rotary drum 2. Each sensor station 15 of the linear array 12 of sensor stations is provided with an excitation light source 11 and a condensing end of an optical fiber 14.

[0007] The shaft 28 of the bell-shaped drum 2 is directed horizontally and is parallel to the door 13 arranged on the front face of the incubator 5 shown in FIG. 2. By directing the shaft 28 horizontally, maximum agitation of the mixture 22 of the liquid culture medium and the specimen in each bottle 1 with the gas is brought about. During the loading operation or the unloading operation, the door 13 is open and access can be had to approximately one-third of all the bottles 1 simultaneously. Next, the drum 2 rotates until the next one-third of the bottles 1 become accessible. Access to all the bottles 1 can be had in three steps.

[0008] Alternatively, the shaft 28 of the bell-shaped drum 2 is oriented vertically and is slightly inclined by approximately 20 degrees from the door 13. In order to maintain optimal growth conditions, the degree of agitation can be corrected by adjusting the inclination angle as required.

[0009] During operation, the bell-shaped drum 2 is rotated by the motor 6 and the belt 7. The circular member 8 and the sensor 9 form an angle encoder that provides information regarding which row of the bottle 1 is passing through the sensor station array 12. Preferably, the motor 6 is a stepper motor that can rotate the drum 2 in a continuous mode or stop the drum 2 at an appropriate angle for reading from the sensing means 20 within the bottle 1 in a steady state mode. The entire system is controlled by a control system 10 disposed inside the rotating drum 2. The output ends of all the optical fibers 14 of the linear array 12 of sensor stations are connected to a single common optical detector (not shown) within the control system 10 such that there is only one excitation light source 11 that needs to be turned on at a time. Thus, the control system "knows" from which detection station 15, and thus from which bottle 1, the sensor light is being collected.

[0010] The devices shown in FIGS. 1 and 2 position the bottles that will be detected by the sensors. However, a solution for any misalignment between the sensors and the bottles continues to be sought. SUMMARY OF THE INVENTION

[0011] This specification describes a system and method for detecting the position (and its changes) of a sample container (e.g., a bottle) held by a rotating drum in a blood culture processing device with respect to a measurement board disposed adjacent to the rotating drum. The system and method of this technology have a measurement and alignment module that can adjust at least one signal provided by a sensor of the measurement board based on the detected position of the rotating drum.

[0012] In one aspect, a system for detecting the position of a drum and the bottles held within the drum is described. The system includes a drum-type rack, a measurement board, a plurality of timing targets, a target sensor, and a controller. The drum has an outer perimeter and a plurality of receptacles each configured to receive a blood culture bottle. The outer perimeter is disposed about the axis of rotation of the drum. The plurality of receptacles are arranged in the drum as an array of receptacles. The array has receptacles disposed in both the vertical and horizontal directions, where the vertically aligned receptacles form columns and the horizontally aligned receptacles form rows. The measurement board is disposed in a stationary position adjacent to the drum and includes an array of sensors configured to interrogate the columns of bottles within the drum that move past the measurement board as the drum rotates about its axis. A plurality of timing targets that rotate with the drum are disposed about the outer perimeter of the drum. The target sensor is disposed in a stationary position adjacent to the drum and is configured to detect one or more characteristics of the timing targets as each timing target moves past the target sensor as the drum rotates about its axis. The controller is configured to identify the position of the drum based on data from the target sensor.

[0013] In one aspect of the system, the identified position of the drum includes a drum offset and a drum angle.

[0014] In one aspect of the system, the controller is configured to detect the position of the drum based on timing data associated with the detected characteristics of the timing targets that move past the target sensor as the drum rotates.

[0015] In one aspect of the system, the timing data includes a timing ratio associated with the plurality of timing targets.

[0016] In one aspect of the system, the controller is configured to normalize the timing ratio.

[0017] In one aspect of the system, the controller is configured to apply the normalized timing ratio to a sine function.

[0018] In one aspect of the system, the controller is configured to calculate a drum offset from the amplitude of the sine application of the normalized timing ratio.

[0019] In one aspect of the system, the controller is configured to calculate a drum angle from the phase of the sine application of the normalized timing ratio.

[0020] In one aspect of the system, the target sensor is an optical sensor.

[0021] In one aspect of the system, the optical sensor is configured to change state when a feature of the timing target blocks the optical path of the optical sensor.

[0022] In one aspect of the system, the controller is configured to detect the position of the drum, at least in part, based on a change in state of the optical sensor.

[0023] In one aspect of the system, one or more features of each timing target include a first edge and a second edge of the timing target.

[0024] In one aspect of the system, the first edge extends radially from the outer circumference of the drum, the second edge includes a first end and a second end, and the radial distance from the outer circumference of the drum to the second edge continuously decreases from the first end of the second edge to the second end of the second edge.

[0025] In one aspect of the system, the first end of the second edge connects to the first edge.

[0026] In one aspect of the system, the second end of the second edge connects to the first edge of an adjacent timing target among a plurality of timing targets.

[0027] In one aspect of the system, each of the plurality of timing targets is aligned perpendicular to a column of receptacles of the drum.

[0028] In one aspect of the system, the controller is configured to adjust at least one signal of at least one sensor in a column of sensors in the measurement board based on a specified position of the drum.

[0029] In one aspect of the system, the at least one signal is a signal stored in the memory of the system.

[0030] In one aspect of the system, the drum has an upper end and a lower end, and the plurality of timing targets are disposed close to the lower end of the drum.

[0031] In one aspect of the system, the target sensor is mounted on the measurement board.

[0032] In one aspect, a method for detecting the position of a drum and the bottles held within the drum is described. The method comprises rotating a drum-type rack having an outer periphery about the axis of rotation of the drum, the drum having a plurality of receptacles each configured to receive a blood culture bottle, and a plurality of timing targets disposed about the outer periphery of the drum and rotating with the drum; accumulating sensor signals from a row of sensors of a measurement board disposed in a fixed position adjacent to the drum, the row of sensors being configured to interrogate a row of bottles within the drum that move past the measurement board as the drum rotates about its axis; accumulating data from a target sensor disposed in a stationary position adjacent to the drum, the target sensor being configured to detect the characteristics of the timing targets as each timing target moves past the target sensor as the drum rotates about its axis; storing the accumulated sensor signals and the accumulated target sensor data in a memory; calculating the position of the drum relative to the stationary measurement board based on the stored target sensor data from the target sensor; and adjusting at least one signal from the stored sensor signals based on the calculated position of the drum.

[0033] In one aspect of the method, the calculated position of the drum includes a drum offset and a drum angle.

[0034] In one aspect of the method, the position of the drum is calculated based on timing data associated with the detected characteristics of the timing targets that move past the target sensor as the drum rotates.

[0035] In one aspect of the method, the timing data includes a timing ratio associated with a plurality of timing targets.

[0036] In one aspect of the method, the method further comprises normalizing the timing ratio.

[0037] In one aspect of the method, the method further includes applying the normalized timing ratio to a sine function.

[0038] In one aspect of the method, the method further includes calculating a drum offset from the amplitude of the sine application of the normalized timing ratio.

[0039] In one aspect of the method, the method further includes calculating a drum angle from the phase of the sine application of the normalized timing ratio.

[0040] In one aspect of the method, the target sensor is an optical sensor.

[0041] In one aspect of the method, the optical sensor is configured to change state when a feature of the timing target blocks the optical path of the optical sensor.

[0042] In one aspect of the method, the position of the drum is calculated based, at least in part, on the change in state of the optical sensor.

[0043] In one aspect of the method, one or more features of each timing target include a first edge and a second edge of the timing target.

[0044] In one aspect of the method, the first edge extends radially from the outer periphery of the drum, the second edge includes a first end and a second end, and the radial distance from the outer periphery of the drum to the second edge continuously decreases from the first end of the second edge to the second end of the second edge.

[0045] In one aspect of the method, the second end of the second edge connects to the first edge of an adjacent timing target of a plurality of timing targets.

[0046] In one aspect of the method, the plurality of timing targets are each aligned perpendicular to a column of receptacles of the drum.

[0047] In one aspect of the method, the drum has an upper end and a lower end, and a plurality of timing targets are disposed proximate to the lower end of the drum.

[0048] In one aspect of the method, the target sensor is mounted on the measurement board.

Brief Description of the Drawings

[0049]

Figure 1

Figure 2

Figure 3A

Figure 3B

Figure 4

Figure 5A

Figure 5B

Figure 5C

Figure 6A

Figure 6B

Figure 6C

Figure 6D

Figure 6E

Figure 7A

Figure 7B

Figure 7C

Figure 7D

Figure 8

Figure 9

Figure 10A

Figure 10B

Figure 10C

Figure 10D-10I

Figure 11

Figure 12A

Figure 12B

Figure 12C

Figure 13

Figure 14

Figure 15A

Figure 15B

Figure 15C

Figure 15D

Figure 15E

Figure 16

Figure 17

Figure 18

Figure 19

Figure 20

Figure 21

Figure 22

Figure 23

Figure 24

Figure 25

Figure 26

Figure 27

Figure 28

Figure 29

Figure 30

Figure 31

Figure 32

Figure 33

Figure 34

Figure 35

Figure 36

DETAILED DESCRIPTION OF THE INVENTION

[0050] In this specification, a blood culture device configured as an incubation and measurement module is described, and the incubation and measurement module can optionally be integrated with a larger end-to-end solution for processing biological samples and determining whether such samples contained are contaminated with or infected by microorganisms. The modules described herein can be placed within a cabinet as shown in FIGS. 3A and 3B. Cabinet 200 can supply power to the modules, provide a controlled thermal environment to the modules, and provide a communication channel to the modules. FIG. 3A shows a cabinet 200 having two three-door panels 201, and the two three-door panels 201 provide access to three bottle drums on both sides of the central panel 202. The central panel 202 has a touch screen 203 for data input and used control. Also, the central panel 202 has a central station 204 for loading / unloading culture bottles. FIG. 3B shows a cabinet having only one three-door panel 201.

[0051] At this time, the number of doors depends on the number of drums. The number of drum racks in the module is mostly a matter of design choice, and in this specification, 1, 2, and 3-drum configurations are contemplated. The devices described herein are not limited to any particular number of drums.

[0052] The module has a high-density bottle drum. By "high-density" is meant, as used herein, a drum configuration that allows culture bottles to be placed closer to each other, enabling more bottles to be stored in the drum compared to the prior art. The module is configured to align the bottles with a limited number of reading stations. That is, the number of reading stations is less than the number of bottle receptacles in the drum. Optionally, the drum is operated by a direct drive motor that can accelerate and decelerate the drum (i.e., oscillatory motion, intermittent rotation, etc.). A heater and a blower are provided within the drum housing or in the space above or below the part of the housing that receives the drum internally. The heater and the blower circulate warm air around the drum. Optionally, the heater and the blower are configured to maintain the temperature of the contents of all the culture bottles within the drum within a predetermined narrow range of a specific target temperature. The predetermined narrow range is ±0.5 °C of the target temperature. The specific target temperature ranges from 30 °C to 40 °C. Optionally, the target temperature is 36.55 °C. Since the risk of the sample "overheating" is reduced, the higher the temperature uniformity, the higher the set value can be. Therefore, the higher the temperature uniformity at high temperatures, the faster the detection time can be. The motor can position the drum so that a user or an automated device can access any bottle held by the drum. When it is determined that the sample in the bottle is positive for microbial growth, a workflow is initiated to retrieve that culture bottle from the module. The module is configured to assist that workflow. The arrangement of the module components such as the blower within the module is mostly a matter of design choice and is not described in detail herein. The module may further include other mechanisms such as vents, baffles, dampers, etc. to further modulate and control the temperature and temperature profile within the module.

[0053] The module is configured to have an LED and a light pipe for indicating a positive culture bottle to the user. Referring to FIG. 4, a top view of an optional configuration of the module described herein is shown. The module 210 has a housing 224, a blower and heater 225 for insulating the bottle 230, and a drum 240 with a receptacle for holding the culture bottle. In the illustrated embodiment, bottle presence sensor electronics 250 and culture bottle presence / status indicator electronics 260 (the BDSI board collectively includes these electronic components) are positioned inside the drum. A drive motor 270 is provided for rotating the drum 240. In other embodiments described herein, the electronics are positioned adjacent to the outside of the drum. The housing 224 of the drum 240 has six panels 221 that define six drum sectors (222A - 222F). As shown, the span of one sector is approximately the same as the span of the opening in the housing where a bottle is added to or removed from the drum 240, so that approximately one-sixth of the drum contents (assuming the drum is full) are available for access at any given time. FIG. 5A is a side view of the drum in FIG. 4. A culture bottle (not shown) is disposed with its neck inwardly in a receptacle 220 within the drum 240 and is received by a cradle configured as a light pipe 515. The motor 270 is a direct drive motor that provides high torque, substantially zero hysteresis, low noise, high reliability, and a simple structure.

[0054] In one aspect, the drum 240 is configured such that the motor assembly 270 and the gearbox 271 are located inside the drum 240. The drum 240 having a receptacle 220 for receiving a culture bottle (the culture bottle is not shown) is shown in FIG. 5A. As described above, the drum 240 is collected within a plurality of sections of the receptacle 220, and the drum 240 (one section of the receptacle 220 has been removed therefrom) is shown in FIG. 5B. The status indication board 273, which is more visible when the panel is removed, is used to illuminate the light pipe 515 to indicate the status of the bottle placed within the light pipe 515. The status indication (BDSI board) board 273 is also detachable and removable from the frame 274 of the drum 240. "Status", as used herein, is the state of the blood culture bottle identified by the module 210. The state of the blood culture bottle can be positive for the growth of microorganisms or negative for the growth of microorganisms. In one aspect, the status of the blood culture bottle is conveyed by color illumination of the bottle receptacle within the drum, and in one aspect, green light indicates that the bottle is negative for the growth of microorganisms and red light indicates that the bottle is positive for the growth of microorganisms. The BDSI board 273 is also configured to indicate the presence of a bottle at the station of the drum or, if no bottle is present at all. The BDSI board 273 is also configured to indicate an error at the station.

[0055] Referring to FIG. 5C, a top view of frame 274 with the status indication board section removed is provided. Cable 275 provides power to motor assembly 270. The bottom 276 of frame 274 is also shown. Drive motor assembly 270 drives drum 240 to rotate axially. The bearings inside the gearbox of drive motor assembly 270 not only provide axial alignment of drum 240, but also provide the essential thrust load support required to advance the drum that holds a number of bottles 230. Referring to FIG. 6A, axis A-A of drive motor assembly 270 is aligned with axis A-A of drum 240. As a result, the center of the center of gravity of drum 240 / drive motor 270 assembly is on the central axis. Drum 240 / drive motor assembly 270 is provided with a lifting mechanism 272 that exposes motor assembly 270 for service by lifting drum 240. In one aspect shown in FIG. 6E, the lifting mechanism is a screw 2720 that advances through motor assembly support plate 2721 and guide nut 2722. When advancing upward, screw 2720 pushes plate 2723 upward. Plate 2723 advances upward along guide pin 2726. This lifts drum 240 away from drum support 2400, creating a lift space 2401 between drum frame 274 and rotor 2724 of motor assembly 270. Referring to FIG. 6C, a locking tool 2402 is provided, and locking tool 2402 is insertable into lift space 2401 to lock the drum in place relative to motor assembly 270 so that the motor can be serviced without the motor carrying the weight of drum 240. An example of a suitable locking tool 2402 is shown in FIG. 6D. Locking tool 2402 has a handle 2403 attached to support bracket 2404 as shown. Locking tool 2402 is inserted between rotor 2724 and drum frame 274 (shown in phantom).While the motor assembly 270 is being serviced, the weight of the rotor 2724 and the drum frame 274 fixed to the rotor via the hex bolts 2725 is supported by the service frame 2405. A detailed view of the lifting assembly 272 is provided in FIG. 6E. The cable 275 provides power to the motor assembly 270. As described above, the screw 2720 is advanced upward through the plate 2721 and the guide nut 2722 to lift the weight of the drum 240 away from the motor assembly 270 for servicing (traveling along the guide pin 2726) by raising the support bracket 2723.

[0056] As described above, the apparatus is provided with a status indication board 273. As described above with reference to FIGS. 5A and 5B, the drum 240 is arranged in a row of receptacles 220 and separated into a plurality of sections each having a plurality of rows (e.g., 4 rows). In one aspect, one row in one section is reserved for the reference bottle. User access to the individual sections within the drum is via a door that provides access to a single section (one of 222A - 222F of the receptacles 220) within the drum 240. A drum divided into sections is shown in FIG. 4.

[0057] To detect the entry and removal of the drum and provide feedback to the user during the user's access to sections 222A - 222F within drum 240, there is a bottle presence sensor 250 (bottle sensor) and a culture bottle / status indicator electronics 260 (e.g., light) on the status indicator board 273. Refer to Figure 7A. Each of the bottle sensors 250 detects when a bottle is inserted into or removed from a receptacle 220 within sections 222A - 222F that are accessible through the door to the drum 240. The indicator light illuminates a light pipe 515 within the drum receptacle 220, thereby transmitting visible light to a user looking through the open door at the receptacle. This requires that the light pipe 515 of the receptacle 220 be aligned with the culture bottle / status indicator electronics 260 within the status indicator board 273. When properly aligned, the module 210 can clearly indicate the status of the bottle (e.g., positive in the case of microbial growth, negative in the case of no microbial growth) and detect when the bottle is inserted or removed.

[0058] To access all the bottles within drum 240, the user must rotate the drum to module 210. As each section of drum 240 comes into view through the open door, the user can have a way to ensure that the exposed section of drum 240 (one of 222A - 222F) is aligned with bottle presence sensor 250 and status indicator light 260 on status indication board 273. Referring to FIG. 7A, in one aspect, module 210 can have an alignment mechanism (disposed on measurement board 545 or BDSI 273) that serves to align receptacle 220 within drum 240 with bottle presence sensor 250 and status indicator light 260 provided on status indication board 273. One skilled in the art will understand that the alignment can be achieved in many different ways and that the alignment mechanism is just one example of a sensor that can be used to align the drum 240 with the module door and thus achieve alignment of the bottle receptacle with the bottle presence sensor 250 and status indicator light 260. Such alignment can be manual (e.g., the operator aligns the drum panel with the door opening), semi - automatic (a mechanism that can be controlled such that the operator incrementally advances the drum until alignment is achieved), or automatic (a detected reference (e.g., an alignment flag) and, based on the detected location, aligning the drum with this reference).

[0059] In one aspect, the alignment mechanism also includes an alignment flag and a section identification flag attached to a drum panel that separates the drum section. The measurement board or BDSI can include an alignment section provided on the measurement board 545 with an optical sensor that detects the flags on the drum panel when the drum rotates and passes through the optical sensor. See FIG. 5B. The BDSI 273 is positioned adjacent to the inside of the drum, whereby the flags on the drum panel 221 can be detected. The optical sensor communicates with the main controller, and the main controller notifies the user / operator of the drum section that can be accessed through the open door in one aspect of the modules described herein.

[0060] The status indication board 273 is also referred to as the bottle detection and status indication (BDSI) board 273. As shown in FIG. 7A, the status indication board 273 is located behind the drum and can be aligned with the door opening. As described above, the module can also have a measurement board 545. In one aspect, the measurement board 545 is the controller board shown in FIG. 7B. Referring to FIG. 13, in one aspect, the measurement board 545 is fixed adjacent to the outside of the drum 240.

[0061] In one aspect, each column of the status indication board 273 can be either a single board or a plurality of interconnected boards. In the aspect shown, the four columns of the status indication board are connected to each other using, for example, a flexible ribbon cable (not shown). The measurement board 545 is connected to a main controller board (not shown) for system communication. As shown in FIG. 7A, the status indication board 273 is mounted inside the drum frame. In contrast, the measurement board 545, which can include an alignment section, is located outside the drum, whereby the flags 2734, 2735 can be detected by the sensors 2739 on the measurement board 545.

[0062] Referring to FIG. 7C, an optional alignment section 2731 can have rows of alignment sensors 2732 and rows of section identifier sensors 2733. In one aspect, all of the alignment sensors and section identifier sensors can be simple optical switches on the measurement board 545. As shown in FIG. 7C, the top row can include four alignment sensors 2732, and the bottom row can include section identifier sensors 2733. The alignment sensors 2732 and section identifier sensors 2733 can each have a notch 2738 where a sensor 2739 (e.g., an optical switch) is disposed. Adjacent sections of the drum 240 can be separated by vertical panels 221 (also called drum ribs or walls) that extend outward from the outer surface of the drum. They are as shown in FIGS. 4 and 6C. As shown in FIG. 4, the drum panels or ribs 221 on either side of a section (222A - 222F) are aligned with the fasteners 2240 of the housing 224 so as to be clearly visible when the user opens the door. As shown in FIG. 5C, the drum rib 221 also extends to the inner surface of the drum.

[0063] Each drum rib 221 inside the drum has a plurality of flags (2734, 2735), namely, one flag 2734 for drum alignment and another set of one or more flags 2735 below the drum alignment flag 2734 for section identification. The flags 2734 and 2735 pass through the notch 2738 and are detected when entering their respective alignment sensors 2732 and section identifier sensors 2733.

[0064] As described above, each panel or rib 221 holds two flags, namely an alignment flag and a section identifier flag. As can be seen in FIG. 7D, the alignment flag can be a continuous flag across all four alignment sensors 2732. When the drum rotates, causing all four optical switches in the alignment sensors 2732 to detect the presence of the flag, this indicates that the drum is aligned. In one aspect, the sensor has an optical beam that transmits through the sensor gap. When the flag enters the gap, the optical beam is blocked, and this blockage is detected as an indication of the presence of the flag. The flag blocks the signal, which is called the "on" state of the sensor. This is because in this state the sensor detects the presence of the flag. The section flag 2735 is configured as a unique identifier for a particular section of the drum. As a result, the size and number of the section flags vary from section to section, such that each section generates a signal unique to that particular section. As shown, the sensor 2739 is positioned within each notch 2738 through which the alignment flag / section identifier flag passes. The sensor is configured as an emitter / receiver pair, only one of which is shown in FIG. 7C. In normal operation, the signal from the emitter to the receiver is not blocked. When the flag passes through the sensor, the flag "interrupts" the optical beam, thereby providing an indication that the flag is present at the sensor. For a clear indication of alignment, the alignment flag must interrupt the optical path of all alignment sensors. At that exact point, the number of "interrupted" signals for the section sensor will indicate where exactly any section is being rotated into place. Referring to FIG. 8, the number of sensors "activated" by the section flag passing through the identifier sensor can notify the control software of which section is present at the sensor location.When the alignment flag 2734 fully activates all the alignment sensors 2732, the section identifier flag 2735 activates the section identifier flag sensor 2733 by a wide margin. This ensures that when the alignment is correct, the correct section of the drum 240 is identified. As described above, the alignment flags are of the same size and configuration for each section, while the section flags each have a unique configuration, such that the signals generated by the section flags indicate a specific section of the drum. As stated above, the alignment mechanism described above is one example of a mechanism that can be used to align the drum. Those skilled in the art will recognize other suitable mechanisms for achieving alignment between the drum and the door and other module electronics (e.g., status indicator board 273).

[0065] The above configuration enables the module controller (e.g., measurement board 545 or BDSI 273) to manage drum alignment without the need to communicate with the main controller. The measurement board 545 can handle the process of assisting the user in aligning the drum with the bottle detection and status indicator board (BDSI) when the module door is opened. The module displays the status of the station whenever an appropriate alignment is identified / shown as described above.

[0066] The main controller can also process the drum alignment before the door is opened, so that when the user opens the door, the bottle status of the visible drum section can already be lit when the user opens the door. In one aspect, the main controller identifies when a local controller (i.e., a controller within the module as opposed to the main controller) activates the status light on the status indication board 273. To start a manual workflow, for example, the main controller can send a command to start alignment to the module controller. From there, the main controller or the module controller can manage the movement and status display of the drum. The local controller can be placed anywhere within the module. In one aspect, the local controller is placed on the measurement board 545. In another aspect, the local controller can be located on the status indication board 273. The door to the module can be opened for a variety of reasons described herein. When the module door is closed, the status indicator light is turned off. A command from the main controller can start the alignment. When the door is about to be opened, the alignment process starts and the drum is advanced until the alignment flag activates all the alignment sensors mounted on the measurement board 545. When alignment is achieved, the local controller can also send to the main controller the specific drum section aligned with the door identified by the section sensor, and the section flag detected when the alignment flag activated the alignment sensor.

[0067] In one aspect, the main controller collaborates with the status indicator board 273 and provides a status map of module 210 based on information from the status indicator board 273. The status map is updated when the user manually inserts or removes a bottle, or when the bottle is added or removed by an automated device that communicates with module 210. When the door to the module is about to be opened, the main controller shares the status map with the status indicator board 273. When a bottle is added or removed from module 210, the map is updated and shared with the main controller. When the module is not operating in the separation mode, the main controller can share the information with the command center.

[0068] In one aspect, the local controller enters an error state and indicates to the user that the module door must be closed. Most of the conditions that can cause the error state are a matter of design choice, but can be things like a drop in module temperature, misalignment, etc.

[0069] As shown in Figure 7A, the status indicator board is equipped with a plurality of lights that can communicate information to the user. The lights are located behind the drum 240 and the bottle receptacle 220, but communicate information to the user through the light pipe 515 within the receptacle 220. In one aspect, the status indicator board 273 can communicate information as a pattern of lights / different colored lights. The light pattern / color / meaning is a matter of design choice. Examples of information communicated include station / receptacle status (blocked, available, etc.) and bottle status (positive, negative, etc.). The status displayed is communicated from the main controller to the local controller.

[0070] The alignment board 545 can communicate with a panel that conveys the alignment status to the user. FIG. 9 is an example of the progression of the displayed alignment status having a plurality of lights for communicating information regarding the alignment status of the device. For example, when the alignment flag 221 is not aligned with the alignment sensor 2731, all the lights are off (545_1). As the drum section moves to be aligned, the columns are illuminated as the flag moves from left to right (first illuminating the left column 545_2) or from right to left (first illuminating the rightmost column 545_3) when starting to activate the alignment sensor. This progression (from left to right or from right to left) of the alignment flag through the alignment sensors is shown for the detection of the alignment flag by the second alignment sensor (545_4; 545_5) or the third alignment sensor (545_6; 545_7). When all four alignment sensors detect the presence of the alignment flag, all the alignment sensor indicator lights are illuminated (545_8). In another aspect, the panel simply communicates no alignment (all lights off) or full alignment (e.g., all lights on).

[0071] When all the alignment sensors are lit, the status indicator changes to station status 273_9, and the user can initiate manual operations such as placing the bottle into the module 210 or removing the bottle from the module 210. The panel still provides an indication of alignment, but some tolerance is incorporated because the drum may move slightly during the manual operation. This prevents causing a misalignment reading that may require a reset of the module. In one example, when full alignment is achieved, the alignment is indicated as long as the leftmost or rightmost alignment sensor continues to detect the presence of the flag. If the flag is not detected by any of the alignment sensors, the local controller can turn all the indicator lights off and a new alignment protocol can be initiated.

[0072] Once alignment is confirmed, panel 273_9, which communicates with status indication board 273, will indicate the status of individual bottles within the receptacle. For example, a light cross-hatched in two directions indicates a sample negative for microbial growth (column 1, row 1, column 2, rows 3 and 8, and column 4, row 5). A light cross-hatched in one direction can indicate a bottle positive for microbial growth (column 1, rows 2, 4, 6, 8 and 9; column 2, rows 1 and 5, column 3, rows 2, 3, 5, 6 and 8; and column 4, rows 2, 7 and 9). An unlit light indicates that no bottle is present at these locations. One advantage of this design is that when the door is open, the user can manually advance the drum. To automatically advance the drum, it is advantageous to close the door so that nothing is caught in the advancing drum. In one aspect, the drum may need to be powered off when the door is open. In that mode of operation, the drum may not be able to be advanced when the door is open.

[0073] In another aspect, as described above in connection with FIG. 9, instead of using a light pipe to convey bottle status, a BDSI panel can be provided outside the drum to convey alignment information. The BDSI controller is connected to the BDSI panel to illuminate indicators that can be light pipes, lenses, etc.

[0074] As described above, the rotating drum rotates beyond the measurement board 545. Since the drum 240 rotates beyond these various detection devices on the measurement board, the measurement is performed in what is described as the "fly-by" format, where fly-by means that the rotating drum moves the bottle beyond the measurement electronics while the measurement value is being created. The measurement value being created elucidates whether the blood culture bottle is positive or negative for microbial growth. Thus, the measurement sensors on the measurement board 545 are provided to interrogate the bottles and determine whether their internal gas composition or pH is dynamic (i.e., changing) in a manner indicative of the metabolic activity inside the bottle as a result of microbial growth. For example, a bottle having an increasing measured carbon dioxide over time or a decreasing measured oxygen concentration can be determined to be positive for microbial growth. To make this determination, a light sensor is directed at chemical sensors inside the bottle that indicate the bottle conditions (e.g., oxygen concentration, carbon dioxide concentration, pH). The location of the chemical sensors inside the bottle will depend on what the sensors are measuring. The headspace inside the bottle is the portion inside the bottle where gas is separated from the liquid and solid in blood culture (i.e., sample, nutrients, etc.).

[0075] Since the culture bottle may be interrogated multiple times before a determination is made as to whether the culture bottle is positive or negative for microbial growth, the measurement conditions must be sufficiently consistent between measurements or, in the case of distance variability, adjustments may need to be made to the measurement values. This means that the light from the interrogation sensor 2501 and the distance from the bottle sensor to the photodiode detector 2602 should remain relatively constant for each measurement value.

[0076] As described above, the bottles are interrogated in columnar units as the drum 240 having the rows of bottle receptacles 222 rotates beyond the measurement board 545. Referring to FIGS. 10A - 10I, a sensor (e.g., light source 5451) and a detector 5452 are fixed to the measurement board 545 and are provided within a housing 5450 that extends from the measurement board 545. The light source 5451 is positioned around a single light detector (photodiode 5452). The housing has a fixing mechanism (flange 5453) for fixing the housing 5450 to the measurement board 273. As shown in FIG. 10B, the housing 5450 has ports 5454, 5455 for receiving the light source 25451 and for receiving the photodiode detector 5452. The ports 5454, 5455 are configured to be angled towards the photodiode detector 5452 such that the light source 5451 surrounds the photodiode detector 5452 and the light emitted by the light source 5451 intersects above the photodiode detector 5452 on a bottle sensor (not shown) that is directly opposite the photodiode detector 5452.

[0077] As the distance between the bottle and the measurement board 545 increases, the signal generated by the photodiode detector 5452 is reduced by the combination of the excitation light from the outwardly spreading light source 5451 and the fluorescence that occurs at the bottle sensor that is further away from the photodiode detector 5452. Since the intersection point of the light from the light source 5451 with respect to the bottle sensor provides consistency between the measured values, the light source 5451 can be placed radially further away from the photodiode 5452. It is advantageous when the light emitted by the light source 5451 intersects the bottle behind the bottle sensor that is directly opposite the photodiode. The intersection point is far enough behind the bottle sensor to offset the illumination of the sensor such that the fluorescence generated by the light source 5451 partially exits the field of view of the photodiode 5452.

[0078] When the bottle moves away from the measurement board 545, the light from the light source 5451 converges to the center of the bottle sensor disposed within the blood culture bottle and thus moves into the field of view of the detector 5452. This additional fluorescence of the sensor caused by additional light from the light source hitting the bottle sensor cancels out the decrease in fluorescence that would otherwise be detected by the detector 5452 due to the bottle and the sensor within the bottle being slightly further away from the detector 5452.

[0079] Referring to FIG. 10C, the housing 5450 has eight light sources 2501 therein. Four of the light sources are of a first color and are designated 12501_1. The light sources are light emitting diodes (LEDs). In one aspect, four of the light sources are of a second color and are designated 12501_2. In one aspect, the first color is green and the second color is cyan. As shown, the colors of the light sources alternate around the photodetector 5452. The housing 5450 having a port 5454 for receiving the light source 5451 and a port 5455 for receiving the photodiode detector 5452 is shown in the upper right. FIGS. 10E - 10J show the optical transitions (from near to far) hitting the bottle sensor. FIGS. 10E - 10G show this transition for the cyan LEDs and FIGS. 10H - 10J show the transition (also from near to far) for the green LEDs. The above design reduces the variation between measurements resulting from differences in the measurements at the distance between the light source / photodetector and the bottle sensor. The intensity of the diffused light source drops in proportion to the square of the distance from the light source. Thus, as the distance between the measurement board 545 and the bottle increases, the photodiode signal resulting from the fluorescence generated by the light from the light source drops. Not only does the intensity of the fluorescence received by the photodiode decrease, but the intensity of the light source light hitting the sensor also decreases.

[0080] Referring to FIG. 11, the bottle drum 240 has a receptacle 220 for receiving a culture bottle disposed with its neck inward, as described above. The receptacle 220 has a light pipe 515 formed at the bottom of the receptacle that also defines the bottom edge of the receptacle 220. The light pipe transmits light through the light pipe structure but is formed of a material that prevents light from being emitted from the light pipe and prevents a large amount of crosstalk from the illuminated light pipe to the non-illuminated light pipe. Examples of suitable materials include polycarbonate (e.g., Makrolon 2258) and acrylic (e.g., polymethyl methacrylate). Makrolon® (formerly Hyzod®) is a trademark of Covestro (formerly Bayer MaterialSciences). All of these materials are polycarbonates, which are very tough and high-impact plastic materials. Although a translucent material is contemplated, a partially transparent light pipe material may make the perception of the color of the light pipe more difficult.

[0081] Referring again to the status indicator board 273, the LEDs that illuminate the light pipe 515 can be a plurality of LEDs that can illuminate the light pipe in a plurality of different colors, each indicating a different status of the blood culture bottle held within the receptacle 220 having the light pipe. In one aspect, the LEDs that illuminate the light pipe are located on the status indicator board approximately 5 mm from the light pipe. As described herein, when the culture bottle status is determined, the BDSI, in conjunction with the local or main controller, determines the color (e.g., red for positive, green for negative, etc.) to illuminate the light pipe 515. The light pipe is configured to provide a color indication of the bottle status and to hold the culture bottle 230 within the drum receptacle 220. In this configuration, the bottom 416 of the culture bottle is fixed within the receptacle by a tab 417.

[0082] FIG. 12A is a perspective view of a light pipe receptacle 515 having a light incident end 419 and a tab 417. The light pipe 515 is configured as a waveguide of an LED positioned at the light incident end. Thus, the light pipe is configured to have total internal reflection so as to be suitable as a waveguide. In one embodiment, the light pipe 515 has a refractive index of about 1.52 higher than the surrounding air. In one embodiment, the light pipe is coated, and the refractive index of the waveguide portion of the light pipe 515 is higher than the refractive index of the coating on the light pipe 515. FIG. 12B is the light incident end 419, and FIG. 12C is the tab 417.

[0083] For the light pipe to have the required total internal reflection, any curves must be either sharp curves or gentle curves without dead ends. A gentle curvature is shown as 421 in FIG. 12A by way of example. In one embodiment, the light pipe has a body length of about 110 mm from the light incident end 419 to the tab 417. For transmission purity, it is advantageous if the presence of foreign matter and air bubbles is minimized. In one embodiment, the light pipe is a molded polyacrylate. Although the use of 3D printing to form the light pipe is contemplated, it is easier to control the quality of the light pipe formed by molding. In one embodiment, the light pipe has very low, almost no, or nearly zero internal absorption and no foreign matter and air bubbles. For example, but not limited to, low or slight internal absorption is less than about 0.2 dBcm -1 less than.

[0084] Referring to FIG. 13, the bottle 230 (facing inward) within the drum 240 is disposed within one of the six sectors (222A - 222F) within the module 210. The sectors are bounded by vertical panels 221 extending outwardly from the drum 240. The span between adjacent panels is approximately equal to the span of the door into the housing 224 such that when a section of the culture bottle is accessed by the user, the user is completely shielded from the inside of the module. The module 210 also includes a blower and heater 225 for insulating the bottle 230. Inside the drum, a status indication board 273 is positioned. A drive motor assembly 270 is provided for rotating the drum 240. The measurement board 545 is positioned outside the drum and performs fly-by measurements of the bottle and drum flags to determine the bottle status and drum alignment respectively.

[0085] Referring to FIG. 14, the receptacle is illuminated using a light pipe 515 to convert light from an indicator LED 520 from the distal end 525 of the receptacle (i.e., the inside of the drum 240 where the receptacle is disposed). The light pipe 515, if present, supports the bottle 230 and extends beyond the proximal end 420 of the receptacle (i.e., the outer surface of the drum 240). A flat spring 510 is pressed against the upper shoulder 535 of the culture bottle 230 to hold the culture bottle 230 against the tab 417. The receptacle 220 is adjacent to the bottle presence detector 250 at the distal end 525 of the receptacle 220. The distal end of the bottle 230 in the receptacle 220 is detected by the bottle presence detector 250. The bottle presence detector 250 is held by the status indication board 273. As shown in FIGS. 15A - 15E, the spring is integrally molded within the bottle holder 220.

[0086] The light pipe 515 aligns exactly with the indicator LED 260 on the status indication board 273. The surface of the end of the light pipe 515 on the outside of the bottle drum 240 is textured to disperse light from the indicator LED 260. The bottle crimp cap 410 blocks the bottle presence detector 250 (e.g., an optical switch or proximity sensor) when placed within the receptacle 220. The indicator LED 260 and the bottle presence detector 536 are disposed on the status indication board 273 positioned inside the drum 240 in an arrangement corresponding to each bottle 230 within the drum 240 accessible by the user. The bottle presence detector 250 is monitored while the door to the module is open for real-time detection when the bottle 230 is placed within or removed from the receptacle.

[0087] Figure 15A shows a portion of the drum 240 having a plurality of vertical rows of receptacles 220. The drum is shown in a cutaway view to show the culture bottle 230 support in the receptacle 220. The upper receptacle 220 is empty. In the embodiment shown in Figure 15A, a pivoting arm 551 is provided to secure the culture bottle 230 within the receptacle 220 instead of the leaf spring 550 described above. As the bottle 230 is advanced into the receptacle 230, the pivoting arm 551 rotates clockwise to secure the culture bottle 230 within the receptacle. Resistance to the pivoting arm 551 is applied by a coil spring 552. The coil spring 552 is fixed within the receptacle by a pin 556.

[0088] An alternative to the receptacle shown in FIG. 15 is shown in FIGS. 15B - 15E. Referring to FIG. 15B, the pivot arm 551 shown in FIG. 15A is replaced by a deformable material 553. In one example, the deformable material 553 is peristaltic tubing, although other conventional deformable materials are contemplated. An important aspect of the deformable material is its elasticity when it returns to its undeformed shape after being deformed by the insertion of the culture bottle into the receptacle. The bottom of the receptacle 220 is a light pipe 515.

[0089] The deformable material 553 is disposed in the tapered portion 554 of the receptacle 220. Referring to FIG. 15C, an end view of the receptacle (220) shows the deformable material 553 (along the tapered portion 554 of the receptacle) at the top of the receptacle. Suitable deformable materials include elastomeric materials and foams in addition to the elastomeric peristaltic tubing described above.

[0090] FIG. 15D is a perspective view of one receptacle 220 with a portion of a second receptacle formed thereon. The culture bottle is held within the receptacle as described above. The tab 417 holds the culture bottle 230 within the receptacle 220. Other materials for the deformable material are contemplated to have sufficient frictional properties when used in contact with the bottle 230. Such friction prevents rotation of the bottle 230, thereby allowing the measurement system to obtain a high - quality signal with less noise caused by bottle vibration due to rack movement. FIG. 15E is a top view of the culture bottle held within the receptacle 220 having the light pipe 515.

[0091] As described herein, the module rotates the drum to position the bottle for both user access and automatic access. The module also rotates the culture bottle to agitate the culture bottle.

[0092] The apparatus according to the present technology described above provides at least the following advantages: 1) noise reduction (i.e., the ratio of the growth signal to the reference signal should not be affected by bottle position, temperature, and sensor variability), 2) detection of growth within the vial after a delay in entry into the system (i.e., the double measurement described above provides a reference such that the contents of the vial do not need to be continuously sampled during growth to confirm a positive by detection of growth acceleration), and 3) a signal quality indicator (i.e., the reference signal is an independent indicator of the health of the station hardware).

[0093] As described above, the fly-by read / measurement technique used with respect to drum 240 and measurement board 545 depends on a relatively constant or fixed distance between the bottles 230 within receptacle 220 of drum 240 and the column sensors on measurement board 545 for measuring and interrogating the bottles 230. Variations in the distance and position of drum 240 relative to measurement board 545 affect the distance between bottles 230 and the corresponding sensors on measurement board 545, and thus affect the fluorescence readings from the media bottles. Such variations in position and distance between measurements can cause noise in the bottle readings. For this reason, the readings obtained from measurement board 545 may be inaccurate during the presence of these variations if not corrected.

[0094] In one aspect, a fully loaded drum weighs between 80 and 90 pounds and can spin at 30 rpm. Drum 240 may tilt slightly, for example, when it becomes unbalanced due to a change in drum loading and when it is rotated for (fluorescence) measurement. A change in the orientation or position of drum 240 relative to board 545 also causes a variation in the distance between the bottles in drum 240 and the corresponding sensors on measurement board 545. Such a variation in distance changes the fluorescence bottle signal (e.g., a decrease in intensity with an increase in bottle distance from the corresponding sensor on measurement board 545 and vice versa). Such a change in distance can result when the drum axis tilts slightly from its normal position.

[0095] Described below are systems and methods for detecting changes in the distance between a bottle and a measurement board that can result from changes in the position or orientation of a drum, according to aspects of the present technology. Further described are systems and methods for offsetting or compensating or adjusting readings obtained by a measurement board in response to detected variations in distance and position. It is understood that aspects of the systems and methods described below can be implemented and used in conjunction with any of the aspects described above with respect to a blood culture device that includes drum 240 and measurement board 545.

[0096] For example, referring to FIG. 16, a block diagram of a measurement system 6000 for detecting the position or orientation of a rotating drum of a blood culture device relative to a fixed measurement board (stationary measurement board) of the blood culture device, according to aspects of the present technology, is shown.

[0097] As shown, system 6000 includes a drum, sensors 6004, an analog / digital (A / D) converter 6008, a controller 6010, and a plurality of timing targets 6002 disposed around the perimeter of one or more memories 6012. It is understood that the components of system 6000 can be separate from the blood culture device components and can represent one or more components of the blood culture device described above. For example, controller 6010 can be any of the controllers or modules described in connection with drum 240, measurement board 545, etc. above, or a separate controller for system 6000.

[0098] As will be described in more detail below, timing targets 6002 can be disposed at discrete locations on (or proximate to) the outer perimeter of the drum. In one aspect, the timing targets are deployed as a continuous series of timing targets along the outer perimeter of the drum. Sensor 6004 for detecting the (features of) timing targets 6002 as they pass through sensor 6004 can be positioned at a location adjacent to the drum (e.g., on a measurement board adjacent to the drum) such that timing targets 6002 pass by and / or through sensor 6004 as the drum rotates. Readings from sensor 6004 can be converted from analog readings to digital readings by A / D converter 6008 for use by controller 6010 to detect the position or orientation (and changes thereof) of the drum and / or to identify changes in the distance between each bottle within the drum and the corresponding sensor on a measurement board fixed adjacent to the rotating drum. Sensor 6004 can also measure the timing at which timing targets 6002 pass by or through sensor 6004, which indicates a change in distance. Controller 6010 (or another controller of the device) is configured to use the changes in distance and / or position to adjust one or more of the stored readings obtained by the sensors on the measurement board with respect to the bottles within the drum.

[0099] In one aspect, during a test cycle, using the system 6000, the initial relative positions of a set of calibrators and reference bottles at some or all of the bottle locations within the drum and sensors at various positions on a stationary measurement board adjacent to the drum are identified, along with fluorescence readings from the calibrators and reference bottles within the drum while they are at these initial relative positions. This information is recorded in a memory such as the memory 6012. Any subsequent change to the recorded initial relative positions is identified or calculated (using measurements obtained from the sensor 6004 with respect to the target 6002) by the controller 6010, and the stored fluorescence readings from each location within the drum are adjusted such that the change in the adjusted readings is due only to a change in the bottles and not a change in the position of the drum with respect to the stationary measurement board.

[0100] Referring to FIGS. 17, 20, 21, and 22, a blood culture device is shown that includes a drum - type rack 6050 (hereinafter the drum), a measurement board 6060, and a measurement system 6000, according to aspects of the present technology. The drum 6050 can include any of the features of the drum 240 described above, and it is understood that the measurement board 6060 can include any of the features of the measurement board 545 described above.

[0101] The drum 6050 includes rows and columns of bottles 6056 held within an array of receptacles disposed around the outer perimeter of the drum. A motor 6054 and a gearbox 6052 are attached to the frame of the drum 6050 via a shaft 6058. The motor 6054 and the gearbox 6052 cooperate to rotate the drum 6050 such that each column of bottles 6056 held within the receptacles of the drum 6050 flies by or passes by a column or set of sensors 6062 on the measurement board 6060 for reading the bottles 6056 as the column of bottles passes by the column of sensors 6062.

[0102] A plurality of targets 6002 are mounted on the outer periphery of the drum 6050 and extend radially therefrom. The targets 6002 are disposed at distinct locations around the outer periphery of the drum 6050. For example, the targets 6002 can be disposed at the lower end of the drum 6050 in each column of the receptacles of the drum 6050, or at each vertical section partition of the drum 6050. Those skilled in the art will understand that the targets 6002 can be disposed at various distinct locations around the drum 6050.

[0103] The position or orientation of the drum 6050 can be defined by three variables. The first variable can be a drum offset, which is the distance from the center of the drum to the center of motion at the level of the target 6002. The second variable can be the angle of the maximum drum offset with respect to the home position of the target 6002 and the drum 6050. The third variable can be a pivot point of the drum, which is the position of the point that restricts the movement of the drum. The pivot point position is measured with respect to the target 6002. An unbalanced drum (e.g., due to the loading of an asymmetric drum receptacle with the bottle 6056) will rock around the pivot point. In one aspect, the pivot point for the drum 6050 is a fixed drive point 6051 in the gearbox 6052. The drum 6050 can pivot only around the pivot point 6051. It is understood that the pivot point for the drum depends on the construction of the drum assembly and is known from the configuration of the assembly. The position of any bottle 6056 (or receptacle containing the bottle) within the drum 6050 can be calculated based on the angles and offsets described above, as well as the position of the pivot point 6051 above the target 6002.

[0104] As shown in FIG. 18, in one aspect, a continuous series of a plurality of targets 6002 extend radially from the outer periphery of a target ring base 6022 mounted or integrated with the drum 6050.

[0105] As shown in FIGS. 17 and 20-22, the inner circumference of the ring base 6022 is shaped such that it is received by a portion of the drum 6050, for example, at the lower edge of the drum 6050 on the opposite side of the gear box 6052 and the motor 6054. The ring base 6022 is mounted on the drum 6050 such that the drum 6050 and the target 6002 rotate together simultaneously.

[0106] In one aspect, the sensor 6004 can be an optical switch having an optical path 6003 (shown in FIG. 19). The switch 6004 is mounted in a fixed position at a selected location such that when the drum 6050 and the target 6002 are rotating, at least a portion of each target 6002 passes through the optical path 6003 of the switch 6004 which is held fixed relative to the movement of the drum in one aspect. As shown in FIGS. 17 and 20-22, in one aspect, the switch 6004 can be mounted on the bottom of the measurement board 6060. In another aspect, the switch 6004 can be mounted separately from the measurement board 6060, spaced apart therefrom, in a fixed position. For example, the switch 6004 can be mounted on the surface of a cabinet in which the drum 6050 is arranged such that at least a portion of each target 6002 passes through the optical path 6003 of the switch 6004.

[0107] Referring to FIGS. 18 and 19, in one aspect, each target 6002 includes a radial edge 6026 that extends radially away from the outside of the drum 6050 and is aligned with the center of the drum. Each target 6002 further includes an edge 6024 that includes a first end 6038 that contacts an end of the radial edge 6026 and, in one aspect, a second end 6040 that contacts the radial edge 6026 of an adjacent target 6002. In another aspect, there may be some distance between the second end 6040 of the first target and the radial edge 6026 of the adjacent target. In any case, the radial distance of the edge 6024 from the outside of the drum continuously decreases from the first end 6038 to the second end 6040. It is understood that the edge 6024 may be curved as shown in FIG. 18 or straight as shown in FIG. 19.

[0108] As the drum 6050 rotates in the rotational direction 6070, the target 6002 moves through the optical path 6003 of the switch 6004. In one aspect, the switch 6004 is configured to be in a first state or a second state depending on whether the optical path 6003 is blocked or not blocked. In one aspect, when a portion of the target 6002 is the blocked optical path 6003, the switch 6004 is in the first state (e.g., open state). When any portion of the target 6002 passes through or blocks the optical path 6003, the switch 6004 is in the second state (i.e., closed state). Thus, when the drum 6050 moves in the rotational direction 6070, the state of the switch 6004 changes from closed to open when some portion of the edge 6024 passes through the optical path 6003, and changes from open to closed when the edge 6026 passes through the optical path 6003. In this way, the state change of the switch 6004 indicates the passage of the optical path 6003 by the edges 6024, 6026.

[0109] Controller 6010 is configured to monitor the state changes of switch 6004. In one aspect, system 6000 includes an A / D converter 6008 configured to receive the changing state of switch 6004 as an analog output signal and convert the analog signal to a digital signal, and this digital signal is provided to controller 6010 and / or memory 6012. In one aspect, switch 6004 is monitored by controller 6010 during A / D reads at a clock rate of approximately (e.g., ±10%) 1 kHz. This clock rate is exemplary, and it is understood that the present disclosure contemplates other suitable clock rates. Controller 6010 is configured to maintain a counter that is incremented by controller 6010 in each clock cycle (e.g., in software stored in memory 6012 and executed by controller 6010, or in a separate processing component of system 6000). The number of clock cycles between state changes of switch 6004 is recorded by controller 6010 in memory 6012.

[0110] From the state changes of switch 6004 and the number of clock cycles between the state changes, controller 6010 is configured to identify the amount of time switch 6004 is open or closed, and the time elapsed between each detection of edges 6024 and 6026 as target 6002 passes through switch 6004. The elapsed time from switch open to switch closed from switch 6004 is proportional to the position of drum 6050 and the distance between drum 6050 and measurement board 6060.

[0111] It is understood that the depth or radial length of the radial edge 6026 of each target 6002 specifies the movement range of the drum 6050 that can be measured. For this reason, the radial length of the radial edge 6026 is selected based on a known movement range or the variation in the distance between the drum 6050 and the measurement board 6060. In one aspect, the radial length of each of the radial edges 6026 is selected to be approximately (±10%) 5 mm, although other radial lengths of the radial edge 6026 are contemplated.

[0112] In one aspect, the controller 6010 is configured to determine that the radial edge 6026 of the target 6002 has been detected when the state of the switch 6004 changes from the open state to the closed state. Further, in this aspect, the controller 6010 is configured to determine that the edge 6024 of the target 6002 has been detected when the state of the switch 6004 changes from the closed state to the open state.

[0113] In one aspect, the controller 6010 can be configured to use the alignment and / or section flags described above to identify which target 6002 passed through the switch 6004. For example, as shown in FIG. 22, in one aspect, the drum 6050 includes a home flag 6061 to be mounted, and the measurement board 6060 includes a home flag sensor 6063 configured to detect when the home flag 6061 passes while being mounted on the measurement board 6060. The first radial edge 6026 of the target detected after the home flag 6061 is detected by the home flag sensor 6063 represents the 0° drum angle of the drum 6050 and identifies the target 6002 associated with that portion of the drum 6050. Data from or representing the readings of sensors 6063 and 6004 is provided to the controller 6010 such that the controller 6010 can detect or determine the drum angle at a given point in time using the data. In this regard, each radial edge 6026 is associated with the drum rotation angle relative to the home position. Thus, by counting the number of radial edges 6026 detected after the home flag 6061 is detected, the controller 6010 can detect the drum angle at that time. For example, as described above, in one aspect, the detection of the first radial edge 6026 after the home flag 6061 is detected represents the 0° drum angle of the drum 6050 and identifies the target 6002 associated with that position of the drum 6050, the detection of the second radial edge 6026 after the home flag 6061 is detected represents the 22.5° drum angle of the drum 6050 and identifies the target 6002 associated with that position of the drum 6050, the detection of the third radial edge 6026 after the home flag 6061 is detected represents the 45° drum angle of the drum 6050 and identifies the target 6002 associated with that position of the drum 6050, and so on. In this way, the controller 6010 is configured to identify the position of each target 6002 and the drum angle at which each target 6002 passes through the switch 6004.It is understood that the angular spacing between the targets 6002 and the drum angles represented by each target are known to the controller 6010 (or stored in and accessible by the memory 6012).

[0114] In one aspect, the controller 6010 is configured to determine the times t1 and t2 shown in FIG. 19 based on the elapsed time between state changes of the switch 6004 and to use the ratio of t1 / t2 to identify a change in the distance between the drum 6050 and the optical switch 6004. Next, the distance between the drum 6050 and the measurement board 6060 can be determined using the distance between the drum 6050 and the optical switch 6004.

[0115] The time t1 is the elapsed time between the point in time when the radial edge 6026 of the preceding target 6002 (e.g., the leftmost target in FIG. 19) is detected via a state change of the switch 6004 (e.g., a change from open to closed) and the point in time when the edge 6024 of the subsequent target 6002 (e.g., the rightmost target in FIG. 19) is detected via a state change of the switch 6004 (e.g., a change from closed to open).

[0116] Furthermore, the time point t2 is the elapsed time between the point in time when the radial edge 6026 of the preceding target 6002 is detected via a state change of the switch 6004 (e.g., a change from open to closed) and the point in time when the radial edge 6026 of the subsequent target 6002 is detected via the same state change of the switch 6004 (e.g., a change from open to closed). In other words, t2 is the time it takes for the entire length of the target 6002 along the rotation direction of the drum 6050 to pass through the switch 6004.

[0117] In one aspect, the controller 6010 is configured to calculate the times t1 and t2 from the number of clock cycles recorded between state changes of the switch 6004 as each target 6002 passes through the switch 6004. The ratio t1 / t2 is calculated by the controller 6010 for each target 6002. The ratio is proportional to the distance between the optical switch 6004 and the outside of the drum 6050 and is used by the controller 6010 to determine the position or orientation of the drum 6050. If it is determined that the position of the drum 6050 has changed (or the distance between the bottle in the drum 6050 and the sensor on the board 6060 has changed), the stored measurement values obtained by the sensors of the measurement board 6060 can be adjusted by the controller (e.g., the controller 6010, the controller of the measurement board 6060, or another controller of the blood culture device) to compensate for such changes.

[0118] Referring to FIG. 23, a graph is shown that depicts drum position identification that can be performed using data derived from switch 6004 according to the present technique. In one aspect, the length of the radial edge 6026 is multiplied by the ratio of t1 / t2 by controller 6010 for each individual target 6002, and distance measurements of each individual target 6002 at a particular angle of target 6002 and drum 6050 are obtained. The angle of target 6002 is the same as the drum angle and is understood to represent the number of degrees that drum 6050 has rotated since (after detection of) the home flag position. Controller 6010 is configured to calculate distance measurements of target 6002 at multiple angles (ranging from 0 to 360°) and to fit the calculated distances at each angle to a sine function, as shown in FIG. 23. It is understood that each of the distance measurements (the boxes in the chart) in FIG. 23 corresponds to a different one of the plurality of targets 6002. In this regard, each measurement corresponds to the target 6002 that is currently at optical switch 6004 during rotation. By fitting the calculated distances to the sine function, noise in the individual distance readings is reduced. The amplitude of the sine fit indicates the offset of the drum position. For example, in FIG. 23, the amplitude is 0.9 mm, which represents the maximum offset of the drum position from its center of rotation. The phase of the sine fit indicates the angle of the drum relative to the home angle at which the maximum offset occurs. For example, in the chart of FIG. 23, the phase is 45°, which represents the angle of the drum position. In this way, using the measurements from switch 6004 (and home sensor 6063), controller 6010 is configured to identify the offset of the drum position and the angle of the drum position.

[0119] During use, the drum 6050 is operated in a "test cycle", which is associated with calibration of the drum 6050 and data collection that occurs during normal use of the drum 6050. The test cycle is a process in which fluorescence data (from sensor 6062) is collected from bottles within the drum 6050 and timing data is collected from the target sensor 6004. Each test cycle can include several rotations of the drum 6050, during which the target ratio of each target 6002 and the fluorescence data of the bottles within the drum 6050 are collected for each rotation of the drum 6050. The test cycle can be performed during calibration of the drum (e.g., at the manufacturing stage) or during normal use of the drum. Calibration can be performed during the final inspection of the equipment during manufacturing with the calibrator bottle filled in the drum 6050. The data collected during the test cycle that occurs during calibration is stored as drum normalization parameters (described later). The data is also collected during the test cycle during normal use of the drum 6050 (e.g., to test the culture bottle readings to detect positive bottles). Thus, the test cycle is performed both during calibration and during normal use of the drum 6050. The data collected during calibration and normal use is the same, but the data collected during calibration is stored as drum normalization parameters. The test cycle process can be controlled by the controller 6010, where the user can select whether the test cycle is being performed for calibration (and thus the data is stored as normalization parameters) or during normal use of the drum (and thus the data is stored for later adjustment if necessary).

[0120] In one aspect, the columns of drums 6050 include reference bottles (also called calibrator bottles) that are fixed at all positions of the columns of drums 6050. The characteristics and contents of these bottles are known. The reference bottles within the reference bottle columns remain in place both during calibration and normal use of the drums 6050. In one aspect, the reference bottles within the reference bottle columns cannot be removed by the user. During calibration, the remaining columns (other than the reference bottle columns) can be filled with calibrator bottles. During normal use, the remaining columns (other than the reference bottle columns) can be filled with culture bottles that will be tested using the measurement board 6060.

[0121] In one aspect, the normalization parameters of drum 6050 are collected during manufacturing in a test cycle and then used to normalize the read values of the media bottles stored in drum 6050 (obtained from sensor 6062) and the timing ratios calculated for each target 6002. For example, during calibration of drum 6050 during manufacturing, all drum stations (receptacles for receiving bottles) within drum 6050 are loaded with calibrator bottles. As described above, the columns of reference bottles are fixed at all positions of the reference bottle columns within drum 6050. In addition, all columns other than the reference bottle column of drum 6050 are filled with calibration bottles. Thus, all stations or receptacles within drum 6050 are filled with reference / calibrator bottles. During the test cycle, drum 6050 is then rotated at a constant measurement speed and fluorescence read values are obtained from the calibrator bottles and reference bottles via the measurement board 6060. Further, the timing ratio t1 / t2 for each target 6002 is calculated using timing data derived from switch 6004 for each of these targets 6002 as the target 6002 passes through the measurement board 6060. The collection of fluorescence read values and timing ratios is stored in memory (e.g., memory 6012) as the normalization parameters of drum 6050.

[0122] Next, during each subsequent test cycle, for example, during normal use of the drum 6050, the position of the drum 6050 is identified by the controller 6010 and used to calculate the change in the distance between each bottle within the drum and its corresponding sensor within the measurement board 6060 relative to the same distance measured when the drum is normalized. The controller 6010 is configured to adjust the stored fluorescence readings from the bottles to take into account the change in distance when the change in distance is measured, using the change in the distance between the bottle and its corresponding sensor in the measurement board 6060. The adjustment is performed on the stored raw fluorescence readings of all bottles, including the reference bottles within the reference bottle array.

[0123] Referring to FIG. 24, a method 7000 is shown for detecting the position or orientation of a rotating drum, such as drum 6050, relative to a stationary measurement board, such as measurement board 6060, according to aspects of the present technology, and processing the stored measurement values of the measurement board based on the detected position of the drum. It is understood that the test cycles and steps of method 7000 can be performed during calibration of the drum 6050 and also during normal use of the drum 6050.

[0124] In step 7002, a test cycle of the blood culture device is initiated. In one aspect, during the test cycle, all stations within the drum 6050 are loaded with calibration bottles. The array of reference bottles is fixed at all positions of the reference bottle array within the drum 6050. The drum 6050 is rotated in the rotational direction 6070 at a predetermined constant measurement speed.

[0125] In step 7004, during the test cycle, the timing ratio (t1 / t2 as described above) of each target 6002 is calculated by the controller 6010 and stored and memorized in a memory (for example, the memory 6012 of the system 6000 and / or another memory of the blood culture device). Further, the reading value of the sensor 6062 on the measurement board 6060 of the bottle stored in the receptacle of the drum 6050 is also stored and memorized in the memory. As described above, the test cycle can include several rotations of the drum 6050.

[0126] In step 7006, it is determined whether the blood culture device (i.e., the drum 6050) should be normalized with respect to the measurement board 6060. The normalization of the drum 6050 is performed using a calibrator bottle at all stations of the drum 6050. If it is determined in step 7006 to normalize the drum 6060, the method proceeds to step 7008. The determination in step 7006 can be based on the controller 6010 receiving user input (for example, from a technician during manufacturing) to normalize the drum 6050. In one aspect, the normalization is performed when requested by a technician during manufacturing. The technician fills the drum 6050 with a calibrator bottle and then requests to execute a test cycle to collect calibration data from the drum 6050 (for example, by an input provided to the controller 6010) in the system.

[0127] In step 7008, the target normalization ratio and the drum station fluorescence normalization parameter are stored in a memory such as the memory 6012 or the measurement board 6060 or the memory of the drum 6050. In one aspect, the target normalization ratio consists of 16 floating-point numbers each corresponding to a different target 6002. Together, the target normalization ratio and the drum station fluorescence normalization parameter form a set of normalization parameters. As described above, the normalization parameters are determined from the data collected when the calibrator bottle is filled in the drum 6050.

[0128] In step 7012, the drum station fluorescence normalization parameters are output for later use in steps 7014 and 7026 during normal use without normalizing the equipment when the test cycle is executed. In particular, the target normalization ratio is provided for use in step 7014, and the drum station normalization parameters are provided for use in step 7026.

[0129] In step 7006, if it is determined not to normalize the drum with respect to the measurement board 6060 (for example, the drum is being operated during normal use), the method proceeds to step 7014. In step 7014, the target ratio accumulated in step 7004 is normalized using the target normalization ratio. For example, in one aspect, the accumulated ratio for each target 6002 is averaged, and the stored normalization ratio is subtracted from each averaged timing ratio. In this regard, the test cycle process includes several rotations of the drum during which the target ratio for each target 6002 for each rotation is collected. The ratios for each target 6002 for all rotations are averaged to reduce the noise in the ratio for each target 6002. Thus, the average target ratio for each target 6002 for the test cycle is calculated. Each resulting average target ratio is subtracted from its corresponding target normalization ratio (the normalization ratio corresponding to a particular target 6002). For example, if the drum position changes, this will result in a set of differences when each average target ratio is subtracted from its target normalization ratio. The set of differences is fitted to a sine wave to indicate how much the drum has moved relative to its position at calibration. Therefore, the drum 6050 with the calibrator from the test cycle is considered the baseline position of the drum 6050 whether or not the drum 6050 is centered.

[0130] In step 7016, the controller 6010 is configured to apply the normalized target timing ratio from step 7014 to a sine function, as described above. This is performed once per test cycle. In step 7018, the controller 6010 is configured to calculate the offset and angle of the drum 6050 from the sine application of step 7016. As described above, the amplitude of the sine application indicates the offset of the drum position, and the phase of the sine application indicates the angle of the drum position. The controller 6010 calculates the amplitude and phase of the sine application. At this point in the method, the position of the timing target 6002 (and the drum 6050) relative to where the timing target 6002 (and the drum 6050) was when the drum 6050 was normalized is determined. Since the target timing ratio was normalized (in step 7014) using the drum normalization parameter, it is understood that the normalized target timing ratio represents the respective positions of the timing targets relative to their positions when the drum 6050 was normalized. For this reason, the position of the timing target and the position of the drum 6050 are the same.

[0131] In step 7022, the controller 6010 is configured to calculate an adjustment value for each drum station. In one aspect, the adjustment value for each drum station is based on the angle of the individual station from the drum offset angle, its height above the timing target 6002, and the height of the pivot point 6051 in the gearbox 6052 (see FIG. 17) relative to the timing target 6002. As shown in 7020, step 7022 receives several constants as input, which are stored in memory. In one aspect, the constants include the percentage signal change of the readings from the measurement board 6060 per mm distance change detected using the timing data from the switch 6004, and the physical dimensions of the drum 6050 such as the drum row angle and the drum row height. It is understood that the percentage signal change of the readings from the measurement board 6060 per mm distance change of the drum 6050 relative to the measurement board 6060 can be identified and stored in memory before the method 7000 is executed. The physical dimensions of the drum 6050 are known.

[0132] In step 7024, the controller 6010 is configured to adjust the raw readings from all drum stations (receptacles) of the drum 6050, including the readings from the reference bottles in the reference bottle row and the readings from the non-reference bottles (i.e., the bottles being tested) in the other rows. In one aspect, the controller 6010 is configured to multiply the raw reading from each station by the adjustment value for that station obtained in 7022. The adjustment for the raw fluorescence readings from each location within the drum 6050 is selected such that the change in the adjusted readings is due only to the change in the bottle and not due to the change in the position of the drum relative to the stationary measurement board 6060.

[0133] In step 7026, the adjusted raw reading from step 7024 is normalized using the drum station normalization parameters received from step 7012. In this regard, the difference between the fluorescence readings from the reference bottles in the reference bottle row during normalization and normal use indicates a change in the measurement system (e.g., due to a change in the position of drum 6050). By controller 6010, a change is applied to the fluorescence readings of the sample bottles in the same row as the reference bottles (i.e., across the circle of stations around the drum) for normalizing the fluorescence readings of the sample bottles. This is performed for all stations of the drum.

[0134] In step 7028, the normalized readings from step 7026 are output to process and adjust the readings from measurement board 6060. After completion of step 7028, the method ends in step 7030.

[0135] The normalization process of FIG. 24 can be performed during the manufacture or normal use of the blood culture device, and the results of FIG. 24 can be used to adjust and correct the stored readings of measurement board 6060 in post - processing after it has been detected that the drum position has changed during use of the drum.

[0136] It is understood that with this technique, the position of the drum (as well as each receptacle and bottle contained therein) can be detected during any operating mode of the drum (e.g., during calibration, normal operation, or any other mode).

[0137] For example, FIG. 36 shows a method 7050 for detecting the position or orientation of a rotating drum, such as drum 6050, relative to a stationary measurement board, such as measurement board 6060, according to an aspect of the present technique, and processing the stored measurement values of the measurement board based on the detected position of the drum.

[0138] In step 7052, a drum - type rack, for example, a drum 6050 having an outer periphery, rotates around the rotation axis of the drum. The drum 6050 includes a plurality of receptacles configured to receive blood culture bottles. Further, as described above, a plurality of timing targets 6002 that rotate with the drum 6050 are disposed around the outer periphery of the drum 6050.

[0139] In step 7054, sensor signals from the columns of sensors 6062 of the measurement board 6060 are accumulated. As described above, the measurement board 6060 is disposed at a fixed or stationary position adjacent to or opposite the outer periphery of the drum 6050. The columns of sensors 6062 are configured to query the receptacles in the columns within the drum 6050 for each column as each column moves past the measurement board 6060 when the drum 6050 rotates about its axis.

[0140] In step 7056, data associated with the target sensor 6004 disposed at a fixed or stationary position adjacent to the drum 6050 is accumulated or obtained. As described above, the target sensor 6004 can be attached to the measurement board 6060 and is configured to detect each geometric feature (e.g., an edge) of each timing target 6002 as each timing target 6002 moves or rotates past (or through) the target sensor 6004 when the drum 6050 rotates about its axis. The data associated with the target sensor 6004 can be data directly received from the target sensor 6004 or data derived from the target sensor 6004. For example, the data can be the timing ratio described above.

[0141] In step 7058, the accumulated sensor signals from the sensors 6062 and the accumulated target sensor data from the target sensor 6004 are stored in a memory such as the memory 6012.

[0142] In step 7060, a controller or processor, such as controller 6010, is configured to calculate or identify the position (or orientation) of drum 6050 relative to stationary measurement board 6060 (or relative to another reference object stationary with respect to drum 6050) based at least in part on the stored target sensor data from target sensor 6004. As described above, the calculated position or orientation of the drum can include a drum offset (the distance of the center of drum 6050 from the axis of rotation of drum 6050) and a drum angle (the angle of the maximum drum offset with respect to the home positions of target 6002 and drum 6050). The drum offset and drum angle can be calculated by applying timing data (e.g., the timing ratio described above) to a sine function and identifying the amplitude and phase of the sine fit. Step 7060 can further include determining the position of each individual receptacle within drum 6050 relative to a fixed or stationary reference object (e.g., measurement board 6060) based on the position of drum 6050. As described above, the physical dimensions of drum 6050, including the position / layout of each receptacle, are known. Further, the pivot point 6051 of drum 6050 is known. From the position of drum 6050, as well as the known dimensions and pivot point of the drum, the position of each individual receptacle (or bottle therein) and the distance from measurement board 6060 can be identified by controller 6010.

[0143] In step 7062, the controller 6010 is configured to calculate an adjustment value and adjust at least one of the sensor signals accumulated from the sensors 6062 of the measurement board 6060. It is understood that the controller 6010 can be configured to determine whether any adjustment is necessary before step 7062 by determining whether there has been a change in the position of the drum 6050 relative to the position of the drum 6050 during the calibration of the drum 6050. If it is determined that an adjustment is necessary, the controller 6010 is configured to calculate an adjustment value and adjust at least one (or all) of the previously accumulated sensor signals from the sensors 6062. As described above, the adjustment value can be based on the change in distance (relative to the home position) between the measurement board 6060 and each bottle / receptacle of the drum 6050.

[0144] Figures 25 to 33 show the results of several drum position detection tests performed using the techniques described above with respect to the system 6000 and the method 7000. Each of Figures 25 to 33 is discussed below.

[0145] Figure 25 shows a radial plot of the position of the drum 6050 under various loading conditions according to the present technology. To obtain the points in the plot of Figure 25, calibration bottles were placed in the receptacles around the drum 6050. A weight was applied to the drum 6050 centered on one column within the drum 6050. Weights were placed in different drum columns of the drum 6050 but were held within the same row, and for each placement, the effects on the angular offset and the distance offset were observed. Fluorescence readings (obtained from the measurement board 6060) from the calibration bottles, and the drum positions, were collected for each weight placement, including the scenario where no weight was placed. The plot in Figure 25 shows the offsets and angles measured using the switch 6004 and the target 6002 for each weight position. The center point does not represent an additional weight. The offset measurements are in millimeters.

[0146] FIG. 26 is a graph according to the present technique of the relationship between the percentage signal change of the measurements from the board 6060 of the bottles stored in the drum 6050 and the change in the distance between the bottle and the sensor on the board 6060 that reads the bottle. The slope of the line in the graph in FIG. 26 indicates the percent change in the fluorescence signal per millimeter change in the distance from the bottle to the sensor (on the board 6060). In the example of FIG. 26, the slope is -13.7% / mm.

[0147] FIG. 27 is a graph according to the present technique of the signal 8004 of the sensor on the board 6060 adjusted based on the drum position change detected using the system 6000 and the techniques described above, and the (raw) unadjusted signal 8002 from the sensor on the board 6060. The unadjusted signal 8002 was recorded when the weight was moved to different positions around the drum 6050. The adjusted signal 8004 was obtained based on the measured offset and angle of the drum 6050 using the switch 6004 and the target 6002, as well as the techniques described above and the bottle position within the drum.

[0148] FIG. 28 shows a radial plot of the position of the drum 6050 under various loading conditions according to the present technique. Calibrator bottles were placed at random positions around the drum 6050. Steel shot filled bottles were placed symmetrically with respect to the rack row located at 0°. Next, weighted bottles were added stepwise symmetrically on the opposite side of the drum 6050 with respect to the rack row located at approximately 192°. The plot in FIG. 28 shows the offset and angle measured using the target 6002 and the switch 6004 for each weight configuration.

[0149] Figure 29 is another graph according to the present technology of the relationship between the percentage signal change of the measured values from the board 6060 of the bottles stored in the drum 6050 and the change in the distance between the bottle and the sensor on the board 6060 that reads the bottle. The slope of the line in the graph in Figure 29 indicates the percent change in the fluorescence signal per millimeter change in the distance from the bottle to the sensor (on the board 6060). In the example of Figure 29, the slope is -15.7% / mm.

[0150] Figure 30 is a graph according to the present technology of the signal 9004 of the sensor on the board 6060 adjusted based on the detected drum position change using the system 6000 and the techniques described above, and the (raw) unadjusted signal 9002 from the sensor on the board 6060. The unadjusted signal 9002 was recorded when the weight was moved to different positions around the drum 6050. The adjusted signal 9004 was obtained based on the measured offset and angle of the drum 6050 using the switch 6004 and the target 6002, as well as the techniques described above and the bottle position within the drum 6050.

[0151] Figure 31 is a radial plot of the position of the drum 6050 under various loading conditions according to the present technology. Calibration bottles were placed around the drum 6050 at random positions. Media bottles were added to one column of the drum 6050, for example column 10, and then individually placed in a range of rows, for example rows 1 - 5 of column 10. Next, media bottles were added in a range of rows, for example rows 1 - 5, in pairs of columns such as columns 9 and 11. The radial plot in Figure 31 shows the offset and angle measured using the target 6002 and the switch 6004 for each media bottle configuration.

[0152] FIG. 32 is another graph according to the present technique of the relationship between the percentage signal change of the measured values from the bottle board 6060 stored in the drum 6050 and the change in the distance between the bottle and the sensor on the board 6060 that reads the bottle. The slope of the line in the graph in FIG. 31 indicates the percent change in the fluorescence signal per millimeter change in the distance from the bottle to the sensor (on board 6060). In the example of FIG. 29, the slope is -21.0% / mm. As with the above graph, the x-axis is the distance change in mm units and the y-axis is the % fluorescence signal change.

[0153] FIG. 33 is a graph according to the present technique of the signal 10004 of the sensor on the board 6060 adjusted based on the detected drum position change using the system 6000 and the techniques described above, and the (raw) unadjusted signal 10002 from the sensor on the board 6060. The unadjusted signal 10002 was recorded as the weight was moved to different positions around the drum 6050. The adjusted signal 9004 was obtained based on the measured offset and angle of the drum 6050 using the switch 6004 and the target 6002, as well as the techniques described above and the bottle position within the drum 6050.

[0154] In one aspect, the measurement system 6000 can include multiple sets of targets 6002 disposed at different locations in the exterior of the drum 6050 and in multiple sets of switches 6004 to detect the timing regarding the passage of the target 6002 through the switch 6004 to detect variations in distance and position with respect to the drum 6050. For example, referring to FIG. 34, the drum 6050 is shown with a first plurality of targets 6002 disposed around the lower end of the drum 6050 and a second plurality of targets 6002 disposed around the upper end of the drum 6050. The switch 6004 is shown mounted on the measurement board 6060 at corresponding locations that allow the first plurality of targets 6002 to pass through the first switch 6004 when the drum 6050 is rotated and allow the second plurality of targets 6002 to pass through the second switch 6004 when the drum 6050 is rotated. The switch 6004 can be vertically aligned with a row of receptacles of the drum or a vertical section partition of the drum. The first plurality of targets 6002 and the second plurality of targets 6002 can also be vertically aligned such that the individual targets of each set are vertically aligned. The target 6002 and the switch 6004 are configured in the manner described above. In this aspect, the controller 6010 is configured to detect a change in the distance between any bottle 6056 within the row of bottles and its corresponding sensor within the measurement board 6060 by interpolating the distances determined at the measurement board and at the top and bottom of the drum based on the layer of the drum in which the bottle is located. The detected distance can be used as described above to adjust the signals of the sensors within the measurement board 6060 as needed.

[0155] In other aspects, it is understood that a target having a different geometric shape and different or additional physical characteristics from the target 6002 shown in FIGS. 17-22 and described above may be used. For example, referring to FIG. 35, a timing target 6092 for use in a system 600 according to another aspect of the present technology is shown. The timing target 6092 includes portions 6094, 6098, and 6096. The timing target 6092 is one of a plurality of timing targets 6092 disposed around (e.g., at the lower end) the drum 6050 so as to pass through the switch 6004 during rotation of the drum. The portions 6094, 6096 extend radially from the drum, and the portion 6098 includes edges 6097, 6099 having the same shape as the edges 6024, 6026 of the target 6002 as described above. The portions 6094, 6098, and 6096 are configured to block the optical path of the switch 6004 such that the controller 6010 can detect the elapsed time between state changes of the switch 6004 when the portions 6094, 6098, and 6096 block the optical path during rotation of the drum. From the state change, the controller 6010 can detect the time points t3 and t4 shown in FIG. 35. The following relationship holds for any speed of the drum as long as the speed is constant.

Number

[0156] When the distance between the drum and the measurement board increases, while t4 increases, t3 + t4 is kept constant, so the ratio in Equation 1 increases. Since both t3 and t4 are proportional to the drum speed, the ratio is independent of the drum speed. The controller 6010 can use the ratio of Equation 1 to detect the position of the drum and the change in the distance between the drum and the measurement, and can adjust the stored readings of the sensors of the measurement board 6060 as described above.

[0157] The above-described drum position detection mode of the present technology describes the use of the optical switch 6004. However, in other modes, it is understood that other types of sensors may be used together with the drum position detection system 6000. For example, the sensor may be a proximity detection device configured to detect the proximity of the drum 6050 (or a target and target features on the drum) to the measurement board 6060. The proximity detection device can have an accuracy on the order of 0.1 mm over a range of 5 to 15 mm and is configured to accurately detect the distance in units of approximately (e.g., ±25%) 1 millisecond when the target passes through the proximity device.

[0158] In one aspect of the above-described drum detection technique, the rotational speed of the drum is intended to be constant while the measurement board 6060 is measuring the bottle. However, in practice, such a constant measurement value may not be guaranteed. In another aspect, an alternative to measuring or specifying the time between interruptions from the optical switch 6004 is to directly measure the distance using an optical encoder strip. In this aspect, the system 6000 includes an optical encoder strip mounted outside the drum 6050 and the encoder. In one aspect, the encoder is added to the measurement board 6060. In another aspect, the encoder is mounted at a stationary position outside the drum 6050 other than the measurement board 6060 such that the optical encoder strip passes through the encoder. The controller 6010, or a controller or processor on the measurement board 6060, accumulates encoder counts as the drum 6050 rotates and captures the number of encoder counts that occur between interruptions from the optical switch 6004. The ratio of the encoder counts replaces the timing to obtain the same ratio that is proportional to the distance between the drum 6050 and the measurement board 6060. For this reason, in this aspect, the controller 6010, or a controller / processor on the measurement board 6060, is configured to use the encoder counts and the ratio of the encoder counts to identify changes in the drum position 6050 and changes in the distance between the drum 6050 and the measurement board 6060.

[0159] It is understood that the above-described aspects regarding drum position detection can also be used to detect potential shape changes or mechanical malfunctions of the drum 6050. For example, as described above, the initial shape of the drum 6050 to be assembled is known. The initial shape can also be specified from the above-described drum normalization parameters. A change in the position of the drum 6050, or a change in the distance between the drum 6050 and the measurement board 6060 with respect to the position or distance detected during manufacturing, can indicate a change in the shape of the drum 6050, such as due to a loose mechanical connection of the drum 6050. The controller 6010 can detect these shape changes based on the detected changes in the drum position or distance with respect to the position or distance detected during manufacturing, and can warn the user of the possibility of a loose mechanical connection that causes a change in the shape of the drum 6050 (e.g., via a communication signal transmitted from the system controller 6010 and / or the communication module). In one aspect, a change with respect to the initial shape is assumed as a possible reason for a change in the position of the drum or a change in the distance between the drum and the measurement board. In this case, the position / distance fluctuates during two measurements respectively performed when the drum is completely unloaded. A change in shape can also be assumed when the change in position or distance is detected from a drum model that normally does not sway even when loaded in a different form or in an unbalanced state.

[0160] Although the drum position detection technique disclosed herein has been described with respect to a blood culture device including a rotating drum, the present technique can be implemented using other devices or systems including a rotating structure that rotates with respect to a stationary structure so as to detect changes in the position of the rotating structure with respect to the stationary structure and changes in the distance at various points between the rotating structure and the stationary structure, and can be used for various purposes.

[0161] In one aspect, a system for detecting the position of a drum and bottles held within the drum is described. The system includes a drum-type rack, a measurement board, a plurality of timing targets, a target sensor, and a controller. The drum has an outer circumference and a plurality of receptacles each configured to receive a blood culture bottle. The outer circumference is disposed about the axis of rotation of the drum. The plurality of receptacles are arranged as an array of receptacles in the drum. The array has receptacles disposed in both the vertical and horizontal directions, with the vertically aligned receptacles forming columns and the horizontally aligned receptacles forming rows. The measurement board is disposed in a stationary position adjacent to the drum and includes an array of sensors configured to interrogate a column of bottles within the drum that move past the measurement board as the drum rotates about its axis. A plurality of timing targets that rotate with the drum are disposed about the outer circumference of the drum. The target sensor is disposed in a stationary position adjacent to the drum and is configured to detect one or more characteristics of the timing targets as each timing target moves past the target sensor as the drum rotates about its axis. The controller is configured to identify the position of the drum based on data from the target sensor.

[0162] In one aspect of the system, the identified position of the drum includes a drum offset and a drum angle.

[0163] In one aspect of the system, the controller is configured to detect the position of the drum based on timing data associated with detected characteristics of the timing targets that move past the target sensor as the drum rotates.

[0164] In one aspect of the system, the timing data includes a timing ratio associated with the plurality of timing targets.

[0165] In one aspect of the system, the controller is configured to normalize the timing ratio.

[0166] In one aspect of the system, the controller is configured to apply the normalized timing ratio to a sine function.

[0167] In one aspect of the system, the controller is configured to calculate a drum offset from the amplitude of the sine application of the normalized timing ratio.

[0168] In one aspect of the system, the controller is configured to calculate a drum angle from the phase of the sine application of the normalized timing ratio.

[0169] In one aspect of the system, the target sensor is an optical sensor.

[0170] In one aspect of the system, the optical sensor is configured to change state when a feature of the timing target blocks the optical path of the optical sensor.

[0171] In one aspect of the system, the controller is configured to detect the position of the drum, at least in part, based on a change in state of the optical sensor.

[0172] In one aspect of the system, one or more features of each timing target include a first edge and a second edge of the timing target.

[0173] In one aspect of the system, the first edge extends radially from the outer circumference of the drum, the second edge includes a first end and a second end, and the radial distance from the outer circumference of the drum to the second edge continuously decreases from the first end of the second edge to the second end of the second edge.

[0174] In one aspect of the system, the first end of the second edge connects to the first edge.

[0175] In one aspect of the system, the second end of the second edge connects to the first edge of an adjacent timing target of a plurality of timing targets.

[0176] In one aspect of the system, each of the plurality of timing targets is aligned perpendicular to a column of receptacles of the drum.

[0177] In one aspect of the system, the controller is configured to adjust at least one signal of at least one sensor in a column of sensors in the measurement board based on a specified position of the drum.

[0178] In one aspect of the system, the at least one signal is a signal stored in the memory of the system.

[0179] In one aspect of the system, the drum has an upper end and a lower end, and the plurality of timing targets are disposed proximate to the lower end of the drum.

[0180] In one aspect of the system, the target sensor is mounted on the measurement board.

[0181] In one aspect, a method for detecting the position of a drum and the bottles held within the drum is described. The method includes rotating a drum-type rack, the drum-type rack having an outer periphery about a rotation axis of the drum-type rack, the drum-type rack having a plurality of receptacles arranged in an array of rows and columns, each receptacle configured to receive a blood culture bottle, an s-d (measurement board) being disposed on the opposite side of the outer periphery of the drum-type rack, the sensor measurement board including a plurality of sensors arranged in columns such that each sensor within the sensor panel is aligned with a receptacle within the drum-type rack, a plurality of timing targets rotating with the drum being disposed about the outer periphery of the drum, each target including a geometric feature extending from the outer periphery of the drum-type rack; rotating; accumulating sensor signals from a column of sensors of a measurement board disposed at a fixed position on the opposite side of the outer periphery of the drum-type rack, the column of sensors being configured to query a receptacle within the drum-type rack for each column as the drum-type rack rotates about its axis and each column moves past the measurement board; obtaining data from a target sensor disposed at a stationary position on the opposite side of the outer periphery of the drum-type rack, the target sensor being configured to detect the geometric feature of each timing target as each timing target rotates past the target sensor as the drum-type rack rotates about its axis; storing the accumulated sensor signals and the target sensor data in a memory; calculating the position of the drum relative to the stationary measurement board based on the stored target sensor data from the target sensor; determining whether at least one signal from the stored sensor signals requires adjustment based on the calculated position of the drum; and adjusting at least one signal from the stored sensor signals if it is determined that adjustment is required.

[0182] In one aspect of the method, the calculated position of the drum includes a drum offset and a drum angle.

[0183] In one aspect of the method, the position of the drum is calculated based on timing data associated with the detected geometric features of a timing target that moves beyond the target sensor as the drum rotates.

[0184] In one aspect of the method, the timing data includes a timing ratio associated with a plurality of timing targets, the timing ratio being based on the amount of time the geometric feature activates the target sensor and the time between when a first geometric feature activates the target sensor and when a subsequent geometric feature activates the target sensor.

[0185] In one aspect of the method, the method further includes normalizing the timing ratio.

[0186] In one aspect of the method, the method further includes applying the normalized timing ratio to a sine function.

[0187] In one aspect of the method, the method further includes calculating a drum offset from the amplitude of the sine application of the normalized timing ratio.

[0188] In one aspect of the method, the method further includes calculating a drum angle from the phase of the sine application of the normalized timing ratio.

[0189] In one aspect of the method, the target sensor is an optical sensor.

[0190] In one aspect of the method, the optical sensor is configured to change state when the geometric feature of the timing target blocks the optical path of the optical sensor.

[0191] In one aspect of the method, the position of the drum is calculated at least in part based on the state change of the optical sensor.

[0192] In one aspect of the method, one or more geometric features of each timing target include a first edge and a second edge of the timing target.

[0193] In one aspect of the method, the first edge extends radially from the outer circumference of the drum, the second edge includes a first end and a second end, and the radial distance from the outer circumference of the drum to the second edge continuously decreases from the first end of the second edge to the second end of the second edge.

[0194] In one aspect of the method, the second end of the second edge connects to the first edge of an adjacent timing target of a plurality of timing targets.

[0195] In one aspect of the method, a plurality of timing targets are each aligned perpendicular to a column of receptacles of the drum.

[0196] In one aspect of the method, the drum has an upper end and a lower end, and a plurality of timing targets are disposed close to the lower end of the drum.

[0197] In one aspect of the method, the target sensor is mounted on the measurement board.

[0198] In this specification, the term "comprising" should be understood in its "broad" sense, i.e., the meaning of "including", and thus is not limited to its "narrow" sense, i.e., the meaning of "consisting only of". The corresponding meaning shall be attributed to the corresponding terms "comprises" and "comprised of" when they appear.

[0199] Although specific embodiments of the present technology have been described above, it will be apparent to those skilled in the art that the present technology can be embodied in other specific forms without departing from the essential characteristics of the present technology. Therefore, these embodiments and examples are illustrative and not restrictive in any way.

[0200] Furthermore, it should be understood that any reference in this specification to a subject matter known in the art does not constitute an admission that such subject matter is widely known to those of ordinary skill in the art to which this technology pertains, unless otherwise indicated.

Claims

1. A drum-shaped rack having an outer circumference, wherein the drum has a plurality of receptacles, each receptacle configured to receive a blood culture bottle, the outer circumference is arranged around the axis of rotation of the drum, the plurality of receptacles are arranged within the drum as an array of receptacles, the array has receptacles arranged both vertically and horizontally, the vertically aligned receptacles form a column, and the horizontally aligned receptacles form a row, A measuring board disposed in a stationary position adjacent to the drum, the measuring board including a row of sensors configured to query a row of bottles in the drum that move beyond the measuring board as the drum rotates around its axis, A plurality of timing targets arranged around the outer circumference of the drum, which rotate together with the drum, A target sensor disposed in a stationary position adjacent to the drum, wherein the target sensor is configured to detect one or more characteristics of the timing targets as each timing target moves beyond the target sensor when the drum rotates around the axis, A controller configured to determine the position of the drum based on data from the target sensor. A system equipped with these features.

2. The system according to claim 1, wherein the specified position of the drum includes drum offset and drum angle.

3. The system according to claim 2, wherein the controller is configured to detect the position of the drum based on timing data associated with detected features of the timing target that move beyond the target sensor as the drum rotates.

4. The system according to claim 3, wherein the timing data includes timing ratios associated with the plurality of timing targets.

5. The system according to claim 4, wherein the controller is configured to normalize the timing ratio.

6. The system according to claim 5, wherein the controller is configured to apply the normalized timing ratio to a sine function.

7. The system according to claim 6, wherein the controller is configured to calculate the drum offset from the amplitude of the sinusoidal fitting of the normalized timing ratio.

8. The system according to claim 6, wherein the controller is configured to calculate the drum angle from the phase of the sinusoidal fitting of the normalized timing ratio.

9. The system according to claim 1, wherein the target sensor is a light sensor.

10. The system according to claim 9, wherein the optical sensor is configured to change state when the characteristics of the timing target block the optical path of the optical sensor.

11. The system according to claim 10, wherein the controller is configured, at least in part, to detect the position of the drum based on a change in the state of the optical sensor.

12. The system according to claim 11, wherein the one or more features of each timing target include a first edge and a second edge of the timing target.

13. The system according to claim 12, wherein the first edge extends radially from the outer circumference of the drum, the second edge includes a first end and a second end, and the radial distance from the outer circumference of the drum to the second edge decreases continuously from the first end of the second edge to the second end of the second edge.

14. The system according to claim 13, wherein the first end of the second edge is connected to the first edge.

15. The system according to claim 14, wherein the second end of the second edge is connected to the first edge of an adjacent timing target of the plurality of timing targets.

16. The system according to any one of claims 1 to 15, wherein each of the multiple timing targets is aligned perpendicularly to the row of receptacles of the drum.

17. The system according to claim 16, wherein the controller is configured to adjust at least one signal from at least one sensor in the row of sensors on the measuring board based on a specified position of the drum.

18. The system according to claim 17, wherein the at least one signal is a signal stored in the system's memory.

19. The system according to claim 17, wherein the drum has an upper end and a lower end, and the plurality of timing targets are arranged in close proximity to the lower end of the drum.

20. The system according to claim 19, wherein the target sensor is mounted on the measuring board.

21. Rotating a drum-shaped rack, wherein the drum-shaped rack has an outer circumference about an axis of rotation of the drum-shaped rack, the drum-shaped rack has a plurality of receptacles arranged in an array of rows and columns, each receptacle configured to receive a blood culture bottle, a sensor measurement board positioned on the opposite side of the outer circumference of the drum-shaped rack, the sensor measurement board includes a plurality of sensors arranged in columns such that each sensor in the sensor panel aligns with a receptacle in the drum-shaped rack, a plurality of timing targets that rotate with the drum are arranged around the outer circumference of the drum, each target includes geometric features extending from the outer circumference of the drum-shaped rack, The method involves accumulating sensor signals from a row of sensors on a measuring board disposed at a fixed position on the opposite side of the outer circumference of the drum-shaped rack, wherein the row of sensors is configured to query a receptacle within the drum-shaped rack for each row as each row moves beyond the measuring board when the drum-shaped rack rotates around its axis. The method involves acquiring data from a target sensor disposed at a stationary position opposite the outer circumference of the drum-type rack, wherein the target sensor is configured to detect the geometric characteristics of each timing target when each timing target rotates beyond the target sensor as the drum-type rack rotates around the axis. The accumulated sensor signals and target sensor data are stored in memory, Based on the target sensor data stored from the target sensor, the position of the drum relative to the fixed measuring board is calculated, Based on the calculated position of the drum, it is determined whether at least one signal from the stored sensor signals requires adjustment. If it is determined that adjustment is necessary, adjust at least one signal from the stored sensor signals. Methods that include...

22. The method according to claim 21, wherein the calculated position of the drum includes a drum offset and a drum angle.

23. The method according to claim 22, wherein the position of the drum is calculated based on timing data associated with the detected geometric features of the timing target which moves beyond the target sensor as the drum rotates.

24. The method according to claim 23, wherein the timing data includes timing ratios associated with the plurality of timing targets, the timing ratios being based on the amount of time that a geometric feature activates the target sensor and the time between when a first geometric feature activates the target sensor and when a subsequent geometric feature activates the target sensor.

25. The method according to claim 24, further comprising normalizing the timing ratio.

26. The method according to claim 25, further comprising fitting the normalized timing ratio to a sine function.

27. The method according to claim 26, further comprising calculating the drum offset from the amplitude of the sinusoidal fit of the normalized timing ratio.

28. The method according to claim 26, further comprising calculating the drum angle from the phase of the sinusoidal fitting of the normalized timing ratio.

29. The method according to claim 21, wherein the target sensor is a light sensor.

30. The method according to claim 29, wherein the optical sensor is configured to change state when the geometric features of the timing target block the optical path of the optical sensor.

31. The method according to claim 30, wherein the position of the drum is calculated at least partially based on a change in the state of the optical sensor.

32. The method according to any one of claims 21 to 28, wherein one or more of the geometric features of each timing target include a first edge and a second edge of the timing target.

33. The method according to claim 32, wherein the first edge extends radially from the outer circumference of the drum, the second edge includes a first end and a second end, and the radial distance from the outer circumference of the drum to the second edge decreases continuously from the first end of the second edge to the second end of the second edge.

34. The method according to claim 33, wherein the first end of the second edge is connected to the first edge.

35. The method according to claim 34, wherein the second end of the second edge is connected to the first edge of an adjacent timing target of the plurality of timing targets.

36. The method according to any one of claims 21 to 28, wherein each of the plurality of timing targets is aligned perpendicularly to the row of receptacles of the drum.

37. The method according to any one of claims 21 to 28, wherein the drum has an upper end and a lower end, and the plurality of timing targets are arranged in close proximity to the lower end of the drum.

38. The method according to any one of claims 21 to 28, wherein the target sensor is mounted on the measuring board.

Images