Patent Publication Number: US-7911778-B2

Title: Vibration isolation within disk drive testing systems

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation and claims the benefit of priority under 35 U.S.C. §120 of U.S. application Ser. No. 12/105,105, filed Apr. 17, 2008. The disclosure of the prior application is considered part of, and is incorporated by reference in, the disclosure of this application. 
    
    
     TECHNICAL FIELD 
     This disclosure relates to isolating vibrations in a disk drive testing system. 
     BACKGROUND 
     Disk drive manufacturers typically test manufactured disk drives for compliance with a collection of requirements. Test equipment and techniques exist for testing large numbers of disk drives serially or in parallel. Manufacturers tend to test large numbers of disk drives simultaneously or in batches. Disk drive testing systems typically include one or more tester racks having multiple test slots that receive disk drives for testing. In some cases, the disk drives are placed in carriers which are used for loading and unloading the disk drives to and from the test racks. 
     The testing environment immediately around the disk drive is closely regulated. Minimum temperature fluctuations in the testing environment are critical for accurate test conditions and for safety of the disk drives. The latest generations of disk drives, which have higher capacities, faster rotational speeds and smaller head clearance, are more sensitive to vibration. Excess vibration can affect the reliability of test results and the integrity of electrical connections. Under test conditions, the drives themselves can propagate vibrations through supporting structures or fixtures to adjacent units. This vibration “cross-talking,” together with external sources of vibration, contributes to bump errors, head slap and non-repetitive run-out (NRRO), which may result in lower yields and increased manufacturing costs. Current disk drive testing systems employ automation and structural support systems that contribute to excess vibrations in the system and/or require large footprints. 
     In some cases, in order to combat undesirable vibrations, disk drives are clamped to a carrier and/or to a tester rack in such a manner as to inhibit or dampen vibrations. A well known way of inhibiting the effects of vibration originating at the disk drive is to mount the disk drive to a mounting device (e.g., a carrier) such that a center of rotation of the mounting device is outside of the footprint of the disk drive. For example,  FIG. 1  shows a conventional disk drive mounting arrangement (e.g., for a disk drive test apparatus  50 ). As shown in  FIG. 1 , the apparatus  50  includes a carrier  52  having a disk drive receiving portion  54  for receiving a disk drive  600  therein. The disk drive  600  is rigidly connected to the carrier  52  (e.g., with fasteners  56  and/or clamps  57 ). The carrier  52  is received in bay  62  of a chassis  60 , which may include plural bays (e.g., multiple rows and or columns of bays). A mounting arrangement supports the carrier  52  within the chassis  60  such that a center of rotation  58  of the carrier  52  is spaced a distance away from the disk drive receiving portion  54  and the disk drive  600 . Known mounting arrangements include, for example, a pin  64  about which the carrier  52  can pivot. Arrow  70  illustrates the resultant movement of the carrier  52  relative to the chassis  60  effected by rotation (arrow  72 ) of a disk  620  of the disk drive  600  in the carrier  52 . 
     SUMMARY 
     In one aspect, a disk drive test slot includes a housing that defines a test compartment for receiving and supporting a disk drive transporter carrying a disk drive for testing. The housing also defines an open end that provides access to the test compartment for insertion and removal of disk drive transporter carrying a disk drive for testing. The disk drive test slot also includes a mounting plate connected to the housing. One or more isolators are disposed between the housing and the mounting plate. The one or more isolators are operable to inhibit transmission of vibrational energy between the housing and the mounting plate. 
     Embodiments can include one or more of the following features. 
     In some embodiments, the main body member includes one or more self-clinching studs connecting the main body member to at least one of the one or more isolators. 
     In some implementations, the one or more isolators include a male-female isolator. The male-female isolator can include a body formed of urethane elastomer. 
     In some embodiments, the one or more isolators include one or more grommets. In some cases, the one or more grommets are displaceable relative to the mounting plate. In some examples, the housing includes a plurality of contact pins each of which engage a corresponding one of the grommets. The contact pins can be disposed at a first end of the housing opposite the open end. The mounting plate can include a main body member, and a flange member connected to main body member and configured to receive and support the grommets. The flange member can be configured to support the grommets in a position spaced apart from the main body member. In some cases, the flange member includes a plurality of forked openings each configured to receive and support one of the grommets. The housing can be connected to the grommets in such a manner as to preload the grommets. The grommets can be formed of thermoplastic vinyl. In some examples, the one or more isolators also include one or more male-female isolators disposed between the housing and the mounting plate. 
     In some embodiments, the one or more isolators include a plurality of said isolators each disposed between the housing and the mounting plate, wherein the plurality of isolators are each operable to inhibit transmission of vibrational energy between the housing and the mounting plate. 
     In some implementations, in the absence of a disk drive and a disk drive transporter, the test slot housing carries substantially no moving parts. 
     According to another aspect, a disk drive testing system includes a plurality of test slots. Each of the test slots includes a housing, and a mounting plate assembly. Each of the housings define a test compartment for receiving and supporting a disk drive transporter carrying a disk drive for testing, and an open end providing access to the test compartment for insertion and removal of disk drive transporter carrying a disk drive for testing. The mounting plate assembly is connected to the housing. The disk drive testing system also includes a chassis that defines a plurality of test slot receptacles each configured to receive and support one of the test slots. Each of the test slot receptacles includes a corresponding card guide assembly configured to releasably engage one of the mounting plate assemblies. 
     Embodiments can include one or more of the following features. In some embodiments the test slots are each independently removable from the chassis. 
     In some implementations, the mounting plate assemblies are operable to inhibit transmission of vibrational energy between the test slot housings and the chassis. 
     In some embodiments, at least one of the mounting plate assemblies includes a mounting plate, and one or more isolators disposed between the mounting plate and an associated one of the test slot housings. The one or more isolators are operable to inhibit transmission of vibrational energy between the associated one of the housings and the mounting plate. The mounting plate can include a mounting flange sized to fit within one of the card guide assemblies to provide a mechanical connection between the associated test slot and the chassis. The one or more isolators can include one or more grommets. In some cases, the grommets are displaceable relative to the mounting plate. The housings can include a plurality of contact pins each of which engages a corresponding one of the grommets. The one or more isolators can include one or a male-female isolators. 
     In some implementations, the chassis includes test electronics configured to communicate a functional test routine to a disk drive within one of the test slots. In some examples, at least one of the test slots also includes a connection interface circuit configured to provide electrical communication between the test electronics and a disk drive within the test compartment of the at least one of the test slots. 
     In some embodiments, the test slots are interchangeable with each other within the test slot receptacles. 
     In yet another aspect, a disk drive testing system includes a plurality of test slots. Each test slot includes a housing defining a test compartment for receiving and supporting a disk drive transporter carrying a disk drive for testing, and an open end providing access to the test compartment for insertion and removal of disk drive transporter carrying a disk drive for testing. Each test slot also includes a mounting plate, and one or more isolators disposed between the housing and the mounting plate. The one or more isolators being operable to inhibit transmission of vibrational energy between the housing and the mounting plate. The disk drive testing system can also include a chassis defining a plurality of test slot receptacles each configured to receive and support one of the test slots. In some cases, the test slots are each independently removable from the chassis. 
     Embodiments can include one or more of the following features. In some implementations, the test slot receptacles are each configured to releasably engage one of the test slot mounting plates thereby mechanically connecting the associated test slot to the chassis. 
     In some embodiments, the isolators are operable to inhibit transmission of vibrational energy between the test slot housings and the chassis. 
     In some implementations, the isolators include grommets. 
     In some embodiments, the isolators include male-female isolators 
     In some implementations, in the absence of a disk drive and a disk drive transporter, the test slot housings carry substantially no moving parts. 
     In some embodiments, the chassis includes test electronics configured to communicate a functional test routine to a disk drive within one of the test slots. In some cases, a first one of the test slots includes a connection interface circuit configured to provide electrical communication between the test electronics and a disk drive within the test compartment of the first one of the test slots. 
     In some implementations, the test slots are interchangeable with each other within the test slot receptacles. 
     In another aspect, a disk drive test slot includes a housing defining a test compartment for receiving and supporting a disk drive transporter carrying a disk drive for testing, and an open end providing access to the test compartment for insertion and removal of disk drive transporter carrying a disk drive for testing. The disk drive test slot can also include a mounting plate connected to the housing, and a plurality of floating contacts disposed between the housing and the mounting plate and operable to inhibit transmission of vibrational energy between the housing and the mounting plate. The floating contacts are displaceable relative to the mounting plate. 
     The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is a schematic view of a disk drive mounting arrangement of the prior art. 
         FIG. 2  is a perspective view of a disk drive testing system. 
         FIG. 3A  is perspective view of a test rack. 
         FIG. 3B  is a detailed perspective view of a slot bank from the test rack of  FIG. 2A . 
         FIG. 4  is a perspective view of a test slot assembly. 
         FIG. 5A  is a perspective view of a transfer station. 
         FIG. 5B  is a perspective view of a tote and disk drive. 
         FIG. 6A  is a top view of a disk drive testing system. 
         FIG. 6B  is a perspective view of a disk drive testing system. 
         FIGS. 7A and 7B  are perspective views of a disk drive transporter. 
         FIG. 8A  is a perspective view of a disk drive transporter supporting a disk drive. 
         FIG. 8B  is a perspective view of a disk drive transporter carrying a disk drive aligned for insertion into a test slot. 
         FIGS. 9 and 10  are schematic views of self-test and functional test circuitry. 
         FIG. 11  is a perspective view of a test slot. 
         FIG. 12  is a perspective view of a mounting plate assembly. 
         FIG. 13  is a perspective view of a male-female isolator. 
         FIGS. 14A-14C  are perspective views of a test slot housing. 
         FIGS. 15A-15D  illustrate assembly of a test slot. 
         FIGS. 16 and 17  are front and rear perspective views of a test slot showing a connection interface board mounted to the test slot housing. 
         FIG. 18  is a perspective view of a test slot showing a rear portion of the test slot housing enclosed by a cover. 
         FIG. 19  is plan view of a test slot with a disk drive therein. 
         FIGS. 20A-20F  illustrate movements of the test housing relative to the mounting plate assembly of the test slot of  FIG. 19 . 
         FIGS. 21A-21C  illustrate movements of a floating center of the housing. 
         FIGS. 22A-22D  illustrate the mounting of test slots within a slot bank of a test rack. 
     
    
    
     Like reference symbols in the various drawings indicate like elements. 
     DETAILED DESCRIPTION 
     System Overview 
     As shown in  FIG. 2 , a disk drive testing system  10  includes a plurality of test racks  100  (e.g., 10 test racks shown), a transfer station  200 , and a robot  300 . As shown in  FIGS. 3A and 3B , each test rack  100  generally includes a chassis  102 . The chassis  102  can be constructed from a plurality of structural members  104  (e.g., extruded aluminum, steel tubing, and/or composite members) which are fastened together and together define a plurality of slot banks  110 . Each slot bank  110  can support a plurality of test slot assemblies  120 . As shown in  FIG. 4 , each test slot assembly  120  includes a disk drive transporter  400  and a test slot  500 . The disk drive transporter  400  is used for capturing disk drives  600  (e.g., from the transfer station  200 ) and for transporting the disk drive  600  to one of the test slots  500  for testing. 
     Referring to  FIG. 5A , in some implementations, the transfer station  200  includes a transfer station housing  210  and multiple tote presentation support systems  220  disposed on the transfer station housing  210 . Each tote presentation support system  220  is configured to receive and support a disk drive tote  260  in a presentation position for servicing by the robot  300 . 
     In some implementations, the tote presentation support systems  220  are each disposed on the same side of the transfer station housing  210  and arranged vertically with respect to the others. Each tote presentation support systems  220  has a different elevation with respect to the others. In some examples, as shown in  FIG. 5A , the tote presentation support system  220  includes tote support arms  226  configured to be received by respective arm grooves  266  ( FIG. 5B ) defined by the disk drive tote  260 . 
     A tote mover  230  is disposed on the transfer station housing  210  and is configured to move relative thereto. The tote mover  230  is configured to transfer the totes  260  between the tote presentation support systems  220  for servicing by the disk drive testing system  10  (e.g. by the robot  300 ) and a staging area  250  where the totes  260  can be loaded into and unloaded from the transfer station  200  (e.g., by an operator). 
     As illustrated in  FIG. 5B , the totes  260  include a tote body  262  which defines multiple disk drive receptacles  264  (e.g., 18 shown) that are each configured to house a disk drive  600 . Each of the disk drive receptacles  264  includes a disk drive support  265  configured to support a central portion of a received disk drive  600  to allow manipulation of the disk drive  600  along non-central portions. The tote body  262  also defines arm grooves  266  that are configured to engage the tote support arms  226  ( FIG. 5A ) of the transfer station housing  210  thereby to support the tote  260  (e.g., for servicing by the robot  300  ( FIG. 2 )). 
     As shown in  FIGS. 6A and 6B , the robot  300  includes a robotic arm  310  and a manipulator  312  ( FIG. 6A ) disposed at a distal end of the robotic arm  310 . The robotic arm  310  defines a first axis  314  normal to a floor surface  316  and is operable to rotate through a predetermined arc about and extends radially from the first axis  314 . The robotic arm  310  is configured to independently service each test slot  500  by transferring disk drives  600  between the transfer station  200  and one of the test racks  100 . In particular, the robotic arm  310  is configured to remove a disk drive transporter  400  from one of the test slots  500  with the manipulator  312 , then pick up a disk drive  600  from one the disk drive receptacles  264  at the transfer station  200  with the disk drive transporter  400 , and then return the disk drive transporter  400 , with a disk drive  600  therein, to the test slot  500  for testing of the disk drive  600 . After testing, the robotic arm  310  retrieves the disk drive transporter  400 , along with the supported disk drive  600 , from one of the test slots  500  and returns it to one of the disk drive receptacles  264  at the transfer station  200  by manipulation of the disk drive transporter  400  (i.e., with the manipulator  312 ). 
     Referring to  FIGS. 7A and 7B , the disk drive transporter  400  includes a frame  410  and a clamping mechanism  450 . The frame  410  includes a face plate  412 . As shown in  FIG. 7A , along a first surface  414 , the face plate  412  defines an indentation  416 . The indentation  416  can be releaseably engaged by the manipulator  312  ( FIG. 6A ) of the robotic arm  310 , which allows the robotic arm  310  to grab and move the transporter  400 . As shown in  FIG. 7B , the face plate  412  also includes beveled edges  417 . When the frame  410  is inserted into one of the test slots  500 , the beveled edges  417  of the face plate  412  abut complimentary beveled edges  562  ( FIG. 14A ) of the test slot  500  to form a seal, which, as described below, helps to inhibit the flow of air into and out of the of the test slot  500 . This may be particularly beneficial, for example, when disk drive transporters  400  are inserted into and removed from the test slots  500  via a robot  300 . In use, one of the disk drive transporters  400  is removed from one of the test slots  500  with the robot  300  (e.g., by grabbing, or otherwise engaging, the indentation  416  of the transporter  400  with the manipulator  312  of the robot  300 ). The frame  410  defines a substantially U-shaped opening  415  formed by sidewalls  418  and a base plate  420  that collectively allow the frame  410  to fit around the disk drive support  265  ( FIG. 5B ) in the tote  260  ( FIG. 5B ) so that the disk drive transporter  400  can be moved (e.g., via the robotic arm  300 ) into a position beneath one of the disk drives  600  housed in one of the disk drive receptacles  264  of the tote  260 . The disk drive transporter  400  can then be raised (e.g., by the robotic arm  310 ) into a position engaging the disk drive  600  for removal off of the disk drive support  265  in the tote  260 . 
     As illustrated in  FIGS. 8A and 8B , with the disk drive  600  in place within the frame  410  of the disk drive transporter  400 , the disk drive transporter  400  and the disk drive  600  together can be moved by the robotic arm  310  ( FIG. 6A ) for placement within one of the test slots  500 . The manipulator  312  ( FIG. 6A ) is also configured to initiate actuation of a clamping mechanism  450  disposed in the disk drive transporter  400 . A detailed description of the manipulator and other details and features combinable with those described herein may be found in the following U.S. patent application filed Apr. 17, 2008, entitled “Transferring Disk Drives Within Disk Drive Testing Systems”, with inventors: Evgeny Polyakov et al., and having assigned Ser. No. 12/104,536, the entire contents of the aforementioned application is hereby incorporated by reference. This allows actuation of the clamping mechanism  450  before the transporter  400  is moved from the tote  260  to the test slot  500  to inhibit movement of the disk drive  600  relative to the disk drive transporter  400  during the move. Prior to insertion in the test slot  500 , the manipulator  312  can again actuate the clamping mechanism  450  to release the disk drive  600  within the frame  410 . This allows for insertion of the disk drive transporter  400  into one of the test slots  500 , until the disk drive  600  is in a test position with a disk drive connector  610  engaged with a test slot connector  574  ( FIG. 16 ). The clamping mechanism  450  may also be configured to engage the test slot  500 , once received therein, to inhibit movement of the disk drive transporter  400  relative to the test slot  500 . In such implementations, once the disk drive  600  is in the test position, the clamping mechanism  450  is engaged again (e.g., by the manipulator  312 ) to inhibit movement of the disk drive transporter  400  relative to the test slot  500 . The clamping of the transporter  400  in this manner can help to reduce vibrations during testing. A detailed description of the clamping mechanism  450  and other details and features combinable with those described herein may be found in the following U.S. patent application filed Dec. 18, 2007, entitled “DISK DRIVE TRANSPORT, CLAMPING AND TESTING”, with inventors: Brian Merrow et al., and having assigned Ser. No. 11/959,133, the entire contents of the which are hereby incorporated by reference. 
     Referring to  FIG. 9 , in some implementations, the disk drive testing system  10  also includes at least one computer  130  in communication with the test slots  500 . The computer  130  may be configured to provide inventory control of the disk drives  600  and/or an automation interface to control the disk drive testing system  10 . Test electronics  160  are in communication with each test slot  500 . The test electronics  160  are configured to communicate with a disk dive  600  received by within the test slot  500 . 
     Referring to  FIG. 10 , a power system  170  supplies power to the disk drive testing system  10 . The power system  170  may monitor and/or regulate power to the received disk drive  600  in the test slot  500 . In the example illustrated in  FIG. 10 , the test electronics  160  within each test rack  100  include at least one self-testing system  180  in communication with at least one test slot  500 . The self-testing system  180  tests whether the test rack  100  and/or specific sub-systems, such as the test slot  500 , are functioning properly. The self-testing system  180  includes a cluster controller  181 , one or more connection interface circuits  182  each in electrical communication with a disk drive  600  received within the test slot  500 , and one or more block interface circuits  183  in electrical communication with the connection interface circuit  182 . The cluster controller  181 , in some examples, is configured to run one or more testing programs with a capacity of approximately 120 self-tests and/or 60 functionality tests of disk drives  600 . The connection interface circuits  182  and the block interface circuit(s)  183  are configured to self-test. However, the self-testing system  180  may include a self-test circuit  184  configured to execute and control a self-testing routine on one or more components of the disk drive testing system  10 . The cluster controller  181  may communicate with the self-test circuit  184  via Ethernet (e.g. Gigabit Ethernet), which may communicate with the block interface circuit(s)  183  and onto the connection interface circuit(s)  182  and disk drive(s)  600  via universal asynchronous receiver/transmitter (UART) serial links. A UART is usually an individual (or part of an) integrated circuit used for serial communications over a computer or peripheral device serial port. The block interface circuit(s)  183  is/are configured to control power to and temperature of the test slots  500 , and each block interface circuit  183  may control one or more of the test slots  500  and/or disk drives  600 . 
     In some examples, the test electronics  160  can also include at least one functional testing system  190  in communication with at least one test slot  500 . The functional testing system  190  tests whether a received disk drive  600 , held and/or supported in the test slot  500  by the disk drive transporter  400 , is functioning properly. A functionality test may include testing the amount of power received by the disk drive  600 , the operating temperature, the ability to read and write data, and the ability to read and write data at different temperatures (e.g. read while hot and write while cold, or vice versa). The functionality test may test every memory sector of the disk drive  600  or only random samplings. The functionality test may test an operating temperature of air around the disk drive  600  and also the data integrity of communications with the disk drive  600 . The functional testing system  190  includes a cluster controller  181  and at least one functional interface circuit  191  in electrical communication with the cluster controller  181 . A connection interface circuit  182  is in electrical communication with a disk drive  600  received within the test slot  500  and the functional interface circuit  191 . The functional interface circuit  191  is configured to communicate a functional test routine to the disk drive  600 . The functional testing system  190  may include a communication switch  192  (e.g. Gigabit Ethernet) to provide electrical communication between the cluster controller  181  and the one or more functional interface circuits  191 . Preferably, the computer  130 , communication switch  192 , cluster controller  181 , and functional interface circuit  191  communicate on an Ethernet network. However, other forms of communication may be used. The functional interface circuit  191  may communicate to the connection interface circuit  182  via Parallel AT Attachment (a hard disk interface also known as IDE, ATA, ATAPI, UDMA and PATA), SATA, or SAS (Serial Attached SCSI). 
     Test Slot 
     As shown in  FIG. 11 , each of the test slots  500  includes a housing  550  that is mounted to and supported by a mounting plate assembly  502 . As shown in  FIG. 12  the mounting plate assembly  502  includes a mounting plate  504  that includes a main body member  506 , a flange member  508 , and a handle  510 . The main body member  506  also includes a pair of self-clinching studs  512  (one shown), such as available from PennEngineering of Danboro, Pa., which are press fit into through holes  514  in the main body member  506 . The self-clinching studs  512  generally include a threaded screw portion  516  and a head  518  disposed at a first end  517  of the screw portion  516 . As illustrated in  FIG. 12 , the threaded screw portion passes through the through hole  514  in the main body member  506  and the head  518  engages the main body member  506  in a press-fit manner, thereby securing the self-clinching studs  512  against movement relative to the main body member  506 . 
     The mounting plate assembly  502  also includes a pair of isolators (e.g., male-female isolators  520 ). As shown in  FIG. 13 , the male-female isolators  520  generally include a body portion  522  formed from a mechanical vibration isolating material, such as urethane elastomer, e.g., having a durometer of between about 45 shore A and about 60 shore A. The body portion  522  is sandwiched between a female threaded fastener  524 , disposed at a first end  525  of the body portion  522 , and a male threaded fastener  526  male threaded fastener  526  disposed at a second end  527  of the body portion  522 . As illustrated in  FIG. 12 , the male-female isolators  520  are fastened the main body member  506  by screwing the female threaded fastener  524  of the male-female isolators  520  on to one of the self-clinching studs  512 . 
     Referring still to  FIG. 12 , the mounting plate assembly  502  also includes a pair of isolators (e.g., grommets  530 ). The grommets  530  may be formed from a mechanical vibration isolating material, such as thermoplastic vinyl, e.g., having a durometer of between about 45 shore A and about 60 shore A. 
     This multiple isolator arrangement also provides the ability to tune the test slot  500  (e.g., via isolator selection) to better isolate particular frequencies and axes of interest. For example, if a drive was sensitive to y-rotary (rotation about the long axis of the drive), the isolators (e.g., the male-female isolators  520  and/or the grommets  530 ) could be made stiffer (e.g., replaced with harder components) to limit y rotation. As shown in  FIG. 12 , the flange member  508  defines a pair of U-shaped indentures or forked openings  532  each of which is configured to receive and support one of the grommets  530 . The main body member  506  also defines a pair of mounting flanges  534 , which, as discussed below, are configured to form a mounting connection with the test rack chassis  102 . 
     Referring to  FIGS. 14A and 14B , as mentioned above, each of the test slots  500  also includes a housing  550  having a base  552 , first and second upstanding walls  553   a ,  553   b  and first and second covers  554   a ,  554   b . In the illustrated embodiment, the first cover  554   a  is integrally molded with the base  552  and the upstanding walls  553   a ,  553   b . The housing  550  defines an internal cavity  556  which includes a rear portion  557  and a front portion  558 . The front portion  558  defines a test compartment  560  for receiving and supporting one of the disk drive transporters  400 . The base  552 , upstanding walls  553   a ,  553   b , and the first cover  514   a  together define a first open end  561 , which provides access to the test compartment  560  (e.g., for inserting and removing the disk drive transporter  400 ), and the beveled edges  562 , which abut the face plate  412  of a disk drive transporter  400  inserted in the test slot  500  to provide a seal that inhibits the flow of air into and out of the test slot  500  via the first open end  561 . The first upstanding wall  553   a  defines an inlet aperture  551  and an outlet aperture  555 . The inlet and outlet apertures  551 ,  555  extend between an outer surface  559  ( FIGS. 14B and 14C ) of the housing  550  and the internal cavity  556 . 
     As shown in  FIG. 14A , the rear portion  557  of the internal cavity  556  includes a pair of through holes  563  that are configured to receive the male threaded fasteners  526  of the male-female isolators  520  (see, e.g.,  FIGS. 12 &amp; 13 ) therein. As shown in  FIG. 14B , the through holes  563  extend from the internal cavity  556 , through to a pair of counterbore recesses  564  formed along a bottom surface  565  of the base  552  of the housing  550 . As discussed in greater detail below, the counterbore recesses  564  are each configured to receive the body portion  522  of a corresponding the male-female isolators  520  therein. The housing  550  also includes a plurality of mounting holes  549  to receive mounting hardware, e.g., screws, for mounting the second cover member  554   b  and a connection interface board  570  (described below; see also, e.g.,  FIG. 16 ) to the housing  550 . 
     Referring to  FIG. 14C , the housing  550  also includes a pair of contact pins  566  disposed along a second end  567  of the housing  550 . The contact pins  566  are sized to engage the grommets  530  of the mounting plate assembly  502 . The housing  550  is mounted to the mounting plate assembly  502  by first placing the grommets  530  around the contact pins  566 , as shown in  FIG. 15A . Then, the second end  567  of the housing  550  is aligned with the mounting plate  504  such that the contact pins  566  and grommets  530  are substantially aligned with the forked openings  532  in the flange member  508 , as shown in  FIG. 15B . When aligned properly, the male-female isolators  520  will sit at least partially within the counterbore recesses  564  ( FIG. 14B ). As illustrated in  FIG. 15C , following alignment, the housing  550  is displaced relative to the mounting plate  504 , as indicated by arrow  568 , such that the grommets  530  and contact pins  566  come to rest with the forked openings  532  and such that the male threaded fasteners  526  extend through the through holes  563  and into the internal cavity  556 . As shown in  FIG. 15D , with the grommets  530  and contact pins  566  disposed within the forked openings  532 , and with the male threaded fasteners  526  of the isolators  520  extending into the internal cavity  556 , threaded nuts  569  are fastened to the male threaded fasteners  526  thereby providing a secure mechanical connection between the housing  550  and the mounting plate assembly  502 . 
     As shown in  FIG. 16 , the rear portion  557  of the internal cavity  556  houses a connection interface board  570 , which carries the connection interface circuit  182  ( FIGS. 9 and 10 ). The connection interface board  570  extends between the test compartment  560  and the second end  567  of the housing  550 . A plurality of electrical connectors  572  are disposed along a distal end  573  of the connection interface board  570 . The electrical connectors  572  provide for electrical communication between the connection interface circuit  182  and the test electronics  160  (e.g., self test system  180  and/or functional test system  190 ) in the associated test rack  100 . The connection interface board  570  also includes a test slot connector  574 , arranged at a proximal end  575  of the connection interface board  570 , which provides for electrical communication between the connection interface circuit  182  and a disk drive  600  in the test slot  500 . As shown in  FIG. 16 , the test slot housing  550  can also include a ducting conduit  540  disposed within the internal cavity  556 . The ducting conduit  540  is configured to convey an air flow from the inlet aperture  551 , i.e., from a source external to the housing  550 , towards the test compartment  560 . The ducting conduit  540  is configured to direct an air flow underneath a disk drive  600  disposed within the test compartment  560 , with a return air flow to flow over the disk drive  600  and back towards the outlet aperture  555 . An electric heating assembly  726  is disposed within a first opening  542  in the ducting conduit  540  and is configured to heat an air flow being conveyed through the ducting conduit  540 . The electric heating assembly  726  includes a heater heatsink  728  and an electric heating device (e.g., an resistive heater  729 ). The resistive heater  729  is electrically connected to the connection interface board  570 , and is configured for electrical communication with the test electronics  160  (e.g., via the connection interface circuit  182 ). The resistive heater  729  is operable to convert an electric current (e.g., provided by the test electronics  160 ) into heat energy, which is used for heating the heater heatsink  728 , which, in turn, is used to heat an air flow passing through the ducting conduit  540 . In the absence of a disk drive  600  and a disk drive transporter  400 , the housing  500  carries substantially no moving parts. A detailed description of the electric heating assembly  726  and other details and features combinable with those described herein may be found in the following U.S. patent application filed Apr. 17, 2008, entitled “Temperature Control within Disk Drive Testing Systems, with inventor: Brian Merrow, and having assigned Ser. No. 12/105,103, the entire contents of which are hereby incorporated by reference. 
     As shown in  FIG. 17 , the connection interface board  570  overlaps the grommets  530  along the second end  567  of the housing  550 , thereby sandwiching the grommets  530 , or at least a portion thereof, between the flange member  508  and the connection interface board  570 . The connection interface board  570  is fastened to the housing  550 , e.g., with fasteners  576 , in such a manner as to preload the grommets  530 . The grommets  530  are mechanically preloaded to achieve optimum performance of resistance to vibration and shock. Optimum performance of vibration and shock is generally achieved with up to 5 percent preloading of the grommets  530 . 
     Referring to  FIG. 18 , once assembled, the male-female isolators  520  ( FIG. 12 ) permit movement of the housing  550  relative to the mounting plate  504  all six-degrees of freedom (i.e., X, Y, Z, Roll, Pitch and Yaw). The grommets  530  are substantially constrained, within the forked openings  532 , in all directions except for the negative Y-direction. As shown in  FIG. 20A , the grommets  530  and forked openings  532  effectively form a pair of floating contacts (one shown in  FIG. 20A ), i.e., first and second floating contacts  580   a ,  580   b  (see, e.g.,  FIG. 19 ), about which the housing can move (e.g., in a rocking motion) relative to the mounting plate  504 . 
     Referring to  FIG. 19 , vibrations often arise as a result of the rotation, as indicated by arrow  581 , of a disk  620  (e.g., a magnetic disk) within the disk drive  600 . As a result, during testing, rotation of a disk  620  and head movements in the disk drive  600  being tested induces movements of the housing  550 . As illustrated in  FIGS. 20A-20C , this arrangement allows the grommets  530  and contact pins  566  to move within the corresponding forked opening  532  (see also  FIG. 12 ), thereby allowing a displacement of a position of the housing  550  relative to the mounting plate  504 . In particular, the grommets  530  can travel in linear motions, e.g., side-to-side along the X-axis (as indicated by arrow  535  in  FIG. 20A ) and/or front-to-back along the Y-axis (as indicated by arrow  536  in  FIG. 20B ) within the forked openings  532 . The grommets  530  can also travel along the edge  533  of the corresponding forked opening  532 , as indicated by arrows  537  in  FIG. 20C . This, together with the pliable nature of the grommets  530  and isolators  520 , allows for a displacement of position of the housing  550  relative to the mounting plate  504  as well as rotation of the housing  550  relative to the mounting plate  504 . For example, as illustrated in  FIGS. 20D-20F , respectively, this construction allows the housing  550  to rotate, relative to the mounting plate  504 , along or about the X-axis (as indicated by arrow  538  in  FIG. 20D ), the Y-axis (as indicated by arrow  539  in  FIG. 20E ), and/or the Z-axis (as indicated by arrow  541  in  FIG. 20F ). The result is a complex motion of the housing  550  relative to the mounting plate  504  which encompasses all the movements shown and described with regard to  FIGS. 20A-20F . This compliance serves to inhibit transmission of vibration from one of the test slots  500  to other, neighboring test slots  500 . There is, however, no single constraint in the illustrated construction that would restrict any possible motion of the housing  550  relative to the mounting plate  504  to one of rotation around any particular axis or around any fixed point. 
     For example,  FIGS. 21A-21C  illustrate how, in the X-Y plane, there exists no single or fixed center of rotation as the center of rotation assumes a floating position as the housing  550  oscillates rotationally along or about the Z-axis, due in part to translational movements of the housing  550  relative the to the mounting plate  504  along or about the X and Y-axes. As illustrated in  FIGS. 21A-21C , as the housing  550  rocks back-and-forth as indicated by arrows  582  ( FIG. 21A ),  584  ( FIG. 21B ), and  586  ( FIG. 21C ) between the first and second floating contacts  580   a ,  580   b , the center of rotation of the housing  550  shifts from a first point P 1  (shown in  FIG. 21A ), to a second point P 2  (shown in  FIG. 21B ), and then to a third point P 3  (shown in  FIG. 21C ) and so on. Movement of the housing  550  relative to the mounting plate  504  can be further realized by rotation of the housing  550  along or about the X and/or Y-axes (illustrated in  FIGS. 20D and 20E , respectively) with the result being a rotational movement that floats in three dimensions. 
     Moreover, by constraining the grommets  530  and contact pins  566  in the positive Y-direction, the flange members  508  also provide a set of fixed surfaces against which the housing can abut during the insertion of a disk drive transporter  400  (with or without a disk drive  600  therein) into the test compartment  560  of the housing  550  without the opportunity for rotation within the test housing. As illustrated in  FIGS. 22A-22C , each of the slot banks  110  includes a plurality of test slot receptacles  122  each of which is configured to receive and support one of the test slots  500 . Each of the test slot receptacles  122  includes a pair of card guide assemblies  124 . The card guide assemblies  124  are sized to receive the mounting flanges  534  (see, e.g.,  FIG. 18 ) of the mounting plate  504  therein. The card guide assemblies  124  can include, for example, cam locks or thumbscrews, to provide a mechanical connection between the card guide assemblies  124  and the mounting plate assemblies  502 , thereby tying the mounting plate assemblies  502  to ground. Since the card guide assemblies  124  engage only the mounting plate assembly  502 , and not the test slot housing  550 , the housing  550  can move not only relative to the respective mounting plate  504  but also relative to the test rack chassis  102 . In this manner, the mounting plate assemblies  502  operate to support isolation, via the isolators (e.g., male-female isolators  520  and grommets  530 ), between the test rack chassis  102  and the respective test slots  500  and there is no rigid connection between the two. As a result, the transfer of vibrations from one test slot  500  to other test slots  500  within a common test rack  100  is reduced. Such vibrations may, for example, emanate from the rotation of a disk drive  600  within one the test slots  500  or from the insertion and/or removal of a disk drive transporter  400  (with or without a disk drive  600  therein) to and/or from one of the test slots  500 . Vibrations originating within the test racks  100  themselves, e.g., as a result of the rotation of cooling fans within the test racks  100 , are also isolated or damped before reaching the individual test compartments  560  within the test slots  500 . This construction also allows for the individual insertion and removal of the test slots  500  to and from the test racks  100 , as illustrated by  FIG. 22D . 
     Other details and features combinable with those described herein may be found in the following U.S. patent applications filed Dec. 18, 2007, entitled “DISK DRIVE TESTING”, with inventors: Edward Garcia et al., and having assigned Ser. No. 11/958,817; and “DISK DRIVE TESTING”, with inventors: Edward Garcia et al., and having assigned Ser. No. 11/958,788. Other details and features combinable with those described herein may also be found in the following U.S. patent applications filed Apr. 17, 2008, entitled “Disk Drive Emulator And Method Of Use Thereof”, with inventors: Edward Garcia, and having assigned Ser. No. 12/104,594; “Transferring Disk Drives Within Disk Drive Testing Systems”, with inventors: Evgeny Polyakov et al., and having assigned Ser. No. 12/104,536; “Temperature Control within Disk Drive Testing Systems”, with inventor: Brian Merrow, and having assigned Ser. No. 12/105,061; “Bulk Feeding Disk Drives To Disk Drive Testing Systems”, with inventors: Scott Noble et al., and having assigned Ser. No. 12/104,869; “Dependent Temperature Control within Disk Drive Testing Systems”, with inventors: Brian Merrow et al., and having assigned Ser. No. 12/105,069; “Enclosed Operating Area for Disk Drive Testing Systems”, with 18523-079001, inventor: Brian Merrow, and having assigned Ser. No. 12/105,041; and “Temperature Control within Disk Drive Testing Systems”, with inventor: Brian Merrow, and having assigned Ser. No. 12/105,107. The entire contents of all of the aforementioned patent applications are hereby incorporated by reference. 
     A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. Accordingly, other implementations are within the scope of the following claims.