Abstract:
There is provided a testing apparatus for inspecting a head and/or a disk. The testing apparatus includes a positioning apparatus that relatively positions the head and the disk and a controlling apparatus for controlling the positioning apparatuses. The positioning apparatus includes a linear positioning apparatus and a rotational positioning apparatus. The controlling apparatus comprises: a first processor for generating a first command relating to the dynamic positioning of the head or the disk in order to control the rotational positioning apparatus, and a second processor for generating a second command relating to the static positioning of the head or the disk in order to control the linear positioning apparatus. The first and second processors may be the same or different processors.

Description:
CROSS-REFERENCED TO RELATED APPLICATION  
       [0001]     The present invention is a continuation of U.S. patent application Ser. No. 10/909,688, filed on Aug. 2, 2004, which claims priority of Japanese Patent Application No. 2003-293536, filed on Aug. 14, 2003. The content of the above applications is herein incorporated by reference. 
     
    
     1. FIELD OF THE INVENTION  
       [0002]     The present invention pertains to a positioning apparatus for relative positioning of a head and a disk and in particular, relates to a space-saving positioning apparatus with which high-speed positioning is possible.  
       2. DISCUSSION OF THE BACKGROUND ART  
       [0003]     A head/disk testing apparatus is an apparatus for testing a head or disk used in a hard disk drive. Head/disk testing apparatuses comprise a spin stand, an electric measurement part, and a control part for controlling the spin stand and the electric measurement part. The spin stand comprises a disk rotating apparatus for rotating the disk and a positioning apparatus for relative positioning of the disk and the head.  
         [0004]     It is specified that the head is positioned and measured at a pre-determined place on the disk during testing. This pre-determined place is one or more positions with different head read-write properties and becomes the reference place for measurement. The pre-determined place is, for instance, near the inner periphery of the disk, near the outer periphery of the disk, and so forth. Positioning at such a pre-determined place is called static positioning. Static positioning requires a wide positioning range of several 10 mm or more, but high speed is not required. Moreover, there are cases even during actual measurements where the head is finely relatively positioned. For instance, by means of track profile measurements, magnetic signals are written at a pre-determined place on a disk and then, the intensity of the magnetic signals that have been written is measured while continuously positioning in very small intervals close to the pre-determined place in order to measure the intensity distribution of these magnetic signals. This type of positioning during measurements is called dynamic positioning. Dynamic positioning requires high speed, but the necessary positioning range is 1 μm or less.  
         [0005]     There are several types of head positioning apparatuses depending on the positioning system that is used. The X-Y system and the X-θ system are likely to be used in the positioning apparatuses.  
         [0006]     Conventional X-Y positioning apparatuses comprise an XY stage and a piezo stage (for instance, JP (Kohyo) 2003-515,859 (page 7, FIG. 1)). The XY stage is an apparatus for linear positioning of a head in two orthogonal directions. The piezo stage is an apparatus for linear positioning of a head in a single direction. Static positioning is performed by the XY stage. Moreover, dynamic positioning is performed by the piezo stage.  
         [0007]     In addition, a conventional X-θ positioning apparatus comprises an X stage and a rotary positioner (for instance, JP (Kokai) 2000-187,821 (FIG. 1)). The X stage is an apparatus for linear positioning of a head in a single direction. The rotary positioner is an apparatus for rotational positioning of a head. Static positioning is performed by the X stage and the rotary positioner. A means for moving the head in a total of three directions, the X direction and the Y direction of the XY stage and one direction of the piezo stage, is needed with the X-Y positioning apparatus. On the other hand, X-θ positioning apparatuses should have a means for moving the head in a total of two directions, the X direction of the X stage and the direction of rotation of the rotary positioner. Consequently, the X-θ positioning apparatus is characterized in that a means for movement of the head in one direction can be omitted and therefore, its physical size is small and apparatus cost is inexpensive when compared to the XY positioning apparatus.  
         [0008]     However, the X-θ positioning apparatus has a disadvantage in that positioning speed is slow. The reason for this is explained below. The X stage and the rotary positioner of a conventional X-θ positioning apparatus are controlled by a PC. This is because controlling the X stage and the rotary positioner requires multiple complex processes. For instance, static positioning is performed by the X stage and the rotary positioner. An operation whereby coordinates (radius r, skew angle φ) designated by the user are converted to coordinates (x, θ) appropriate for control of the X stage and the rotary positioner before actual positioning is necessary with this static positioning. Moreover, by means of static positioning, the movement path of the head is found before actual positioning so that the moving head does not collide with obstructions. Furthermore, the X stage and the rotary positioner also perform head loading/unloading, and so forth. As previously mentioned, multiple complex processes are necessary for the X stage and the rotary positioner. When these processes are executed by a low-level processor such as a digital signal processor (DSP), or are fully hardware-implemented, the equipment structure and programs become complicated. Complex equipment structure and programs invite an increase in development manpower and development time. There has been considerable progress in technology in the hard disk drive field in recent years and there is an urgent market demand for excellent head/disk testing apparatuses. Moreover, there is a strong demand for a reduction in the cost of head/disk testing apparatuses in order to reduce the manufacturing cost of hard disk drives. In order to respond to the above-mentioned market demands, the X stage and the rotary positioner of the X-θ positioning apparatus are controlled using a PC with an ordinary OS loaded. However, this type of PC lacks real-time processing capability, such as frequent interruption of the OS. Dynamic positioning by the rotary positioner is limited by the PC processing capability and impedes high speed.  
         [0009]     In addition to the above-mentioned demands, there has been a need for curtailment of testing time and reduction of equipment space for head/disk testing apparatuses in recent years. However, head/disk testing apparatuses comprising conventional positioning apparatuses cannot simultaneously satisfy these demands.  
         [0010]     Therefore, the present invention uniquely provides a small-footprint positioning apparatus that is capable of high-speed positioning. Moreover, the present invention also provides a controlling apparatus for controlling this positioning apparatus.  
       SUMMARY OF THE INVENTION  
       [0011]     A positioning apparatus characterized in that a positioning apparatus for the relative positioning of a head and a disk comprising: a processor for generating a positioning command that generates a first positioning command from a second positioning command and a third positioning command; and an apparatus for moving the head or disk based on the first positioning command.  
         [0012]     The processor which generates a positioning command comprises an adder that adds the second positioning command and the third positioning command to generate this first positioning command.  
         [0013]     The processor further comprises memory, wherein a pre-established positioning command is stored in the memory and read to become the second positioning command and the second positioning command is added to the third positioning command.  
         [0014]     The processor further comprises a counter, wherein the output of the counter becomes the second positioning command and the second positioning command is added to the third positioning command.  
         [0015]     The third positioning command is multiplied and input to the adder.  
         [0016]     Either the second positioning command or the third positioning command or both change in synchronization with the rotation of the disk.  
         [0017]     The apparatus for moving the head or the disk is a rotational movement apparatus.  
         [0018]     A testing apparatus for inspecting at least one of a head and a disk, comprising a positioning apparatus for the relative positioning of a head and a disk, the positioning apparatus comprising: a processor for generating a first positioning command from a second positioning command and a third positioning command; and an apparatus for moving the head or the disk based on the first positioning command. The second positioning command is a command relating to the dynamic positioning of the head or the disk, and wherein the third positioning command is a command relating to the static positioning of the head or the disk.  
         [0019]     A controlling apparatus for controlling a positioning apparatus that relatively positions a head and a disk, the positioning apparatus comprising: a linear positioning apparatus; a rotational positioning apparatus; a first processor for generating a first command relating to the dynamic positioning of the head or the disk in order to control the rotational positioning apparatus; and a second processor for generating a second command relating to the static positioning of the head or the disk in order to control the rotational positioning apparatus; wherein the first and second processors may be the same or different processors. The first command is a command representing sin −1 {dr/(L·cos φ)} or {dr/(L·cos φ)} wherein the desired movement distance of the head is dr, the skew angle of the head is +, and the distance between the center of rotation of the rotational positioning apparatus and the head is L. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0020]      FIG. 1  is an oblique view showing head/disk testing apparatus  100 .  
         [0021]      FIG. 2  is a block diagram showing head/disk testing apparatus  100 .  
         [0022]      FIG. 3  is a drawing showing the relative position of head  160  and the status of head/disk testing apparatus  100 .  
         [0023]      FIG. 4  is a block diagram showing head/disk testing apparatus  200 .  
         [0024]      FIG. 5  is a block diagram showing head/disk testing apparatus  300 .  
         [0025]      FIG. 6  is a block diagram showing head/disk testing apparatus  400 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0026]     The rotational positioning apparatus is a rotational positioning apparatus for positioning of a head relative to a disk that comprises a means for moving this head or disk and that is capable of both static positioning and dynamic positioning, and further comprises a means for generating one positioning command to be input to the movement means from two positioning commands. Therefore, static positioning and dynamic positioning can be individually controlled by the movement means. Static positioning and dynamic positioning can be individually controlled and therefore, control of the dynamic positioning can be hardware-implemented, or it can be accomplished with a low-level processing means with which real-time processing is possible, such as a DSP. As a result, dynamic positioning can be high speed.  
         [0027]     The present invention will be discussed based on preferred embodiments shown in the attached drawings. The first embodiment of the present invention is a head/disk testing apparatus and the general structure of this apparatus is shown in  FIG. 1 .  
         [0028]     A head/disk testing apparatus  100  in  FIG. 1  comprises a spin stand  120  and a controlling apparatus  130  connected to spin stand  120 . Spin stand  120  comprises a disk rotating apparatus  150 , which holds and rotates a disk  140 , and a rotational positioning apparatus  180  and a linear positioning apparatus  190 , which position a head  160  relative to disk  140 . In  FIG. 1 , disk rotating apparatus  150  rotates disk  140  counterclockwise, but it can also rotate disk  140  clockwise. Moreover, in  FIG. 1 , head  160  is loaded from underneath disk  140 , but it can also be loaded from above. Rotational positioning apparatus  180  is an apparatus for the rotational positioning of an arm  161  supporting head  160  in direction θ. Linear positioning apparatus  190  is the apparatus for the positioning of rotational positioning apparatus  180  in direction X. Linear positioning apparatus  190  virtually linearly positions arm  161  supporting head  160  in direction X. The coordinates on disk  140  designated by the user (radius r, skew angle φ) are determined by position X of head  160 , which is positioned by linear positioning apparatus  190 , and position  0  of head  160 , which is positioned by rotational positioning apparatus  180 .  
         [0029]     A block diagram of the head/disk testing apparatus  100  will now be shown in  FIG. 2 .  
         [0030]     Controlling apparatus  130  is an apparatus for controlling rotational positioning apparatus  180 , linear positioning apparatus  190 , and disk rotating apparatus  150  of spin stand  120 . Controlling apparatus  130  comprises a CPU  131  and a DSP  132 . CPU is the abbreviation for central processing unit. A positioning command P 2  is a command for the dynamic positioning of head  160  and is generated by DSP  132  and used only for rotational positioning. DSP  132  can generate a positioning command P 1  at a high speed independent from CPU  131 . Here, the length of arm  161 , that is, the distance from the center of rotation of rotational positioning apparatus  180  to head  160 , is L. Moreover, the skew angle of head  160  is φ. The angle of rotation dθ of rotational positioning apparatus  180  necessary for fine movement by dr of head  160  in the direction of the track at this time is dθ=sin −1  {dr/(L·cos φ)}. [The value of] dr is very small and therefore, the angle of rotation dθ becomes dθ≈{dr/(L·cos φ)}. Consequently, positioning command P 2  is the command that represents sin −1 {dr/(L·cos φ)} or {dr/(L·cos φ)}. Positioning command P 2  should be transmitted at high speed for high-speed control of rotational positioning apparatus  180 . Thus, it is preferred that positioning command P 2  is the command representing {dr/(L·cos φ)}. Moreover, a positioning command P 3  and a positioning command P 4  are commands for the static positioning of head  160  and are generated by CPU  131 . Positioning command P 3  is used for rotational positioning. Positioning command P 4  is used for linear positioning. Positioning command P 3  and positioning command P 4  are related to one another and are calculated from the coordinates (radius r, skew angle φ) on disk  140  designated by the user. In addition, controlling apparatus  130  outputs rotation command R that designates the number of revolutions per unit time of disk  140 . Rotation command R can be output from either CPU  131  or DSP  132 , or it can be output from another apparatus.  
         [0031]     Rotational positioning apparatus  180  receives positioning command P 2  and positioning command P 3  from controlling apparatus  130 . Rotational positioning apparatus  180  comprises a multiplier  181 , an adder  182 , a rotational movement part  183 , and a position detector  184 . Multiplier  181  is the apparatus for multiplying positioning command P 3  by N and outputting this to adder  182 . N is any number. Adder  182  adds positioning command P 2  and positioning command P 3  that has been multiplied by N by multiplier  181  and outputs this to rotational movement part  183 . The output command of adder  182  is positioning command P 1 . The device under test is head  160  held by arm  161 . Position detecting part  184  detects the position or amount of rotation of rotational movement part  183 . Rotational movement part  183  moves the device under test to the place designated by positioning command P 1  while referring to the results detected by position detecting part  184 .  
         [0032]     Linear positioning apparatus  190  receives positioning command P 4  from controlling apparatus  130 . Linear positioning apparatus  190  moves the device under test to the place designated by the positioning command P 4 .  
         [0033]     Disk rotating apparatus  150  receives rotation command R from controlling apparatus  130 . Disk rotating apparatus  150  rotates disk  140  by the number of revolutions per unit time specified by rotation command R. Moreover, disk rotating apparatus  150  outputs a period signal S synchronized with the rotation of disk  140 . For instance, period signal S is an index signal, sector signal, and so forth.  
         [0034]     As previously described, the positioning apparatus comprises a means for generating a first positioning command P 1  to be input to rotational movement part  183  from positioning command P 2  and positioning command P 3 . Therefore, controlling apparatus  130  is capable of individually controlling both static positioning and dynamic positioning by rotational movement part  183 . Thus, a control system optimal for dynamic positioning can be made. By means of the present embodiment, controlling apparatus  130  comprises inexpensive DSP  132  capable of executing simple operations at a high speed as a special processor for the dynamic positioning.  
         [0035]     Moreover, controlling apparatus  130  receives period signals S output from disk rotating apparatus  150 . Head/disk testing apparatus  100  performs the relative positioning of head  160  in synchronization with this period signal S and curtails the real time needed for positioning. The details will be described while referring to  FIG. 3 .  FIG. 3  is a drawing showing the position of head  160  and the status of head/disk testing apparatus  100  during the measurement of a certain measurement item. The head position in  FIG. 3  is a graph showing the relative position of the head on a track on the disk. Head/disk testing apparatus  100  measures the properties of head  160  and disk  140  by reading data relating to the track and sector on disk  140 . It is necessary to start at the beginning of a track or a sector when reading data on this track or sector. There are cases where the beginning of a track or sector is passed over during positioning when head  160  is relatively positioned without regard for the beginning of the track or sector. Head/disk testing apparatus  100  will not start the measurement until it reaches the beginning of the next track or sector and useless wait time is produced as a result (refer to head position (non-synchronized) in  FIG. 3 ). If head/disk testing apparatus  100  is adapted to the relative positioning of head  160  in synchronization with period signal S, generation of the above-mentioned useless wait time can be controlled. Moreover, if the time needed for the relative positioning of head  160  is curtailed so that it falls within the period during which the start of the track or sector emerges, none of the above-mentioned useless wait time will occur (refer to head position (synchronized) in  FIG. 3 ). Relative positioning in synchronization with period signal S is realized by changing positioning command P 2  in synchronization with period signal S.  
         [0036]     Dynamic positioning performs successive positioning at multiple pre-determined positions. Consequently, the control of dynamic positioning can further be hardware-implemented. A second embodiment that has been adapted to the hardware-implemented control of dynamic positioning is described below.  
         [0037]     The second embodiment of the present invention is a head/disk testing apparatus and a block diagram of this is shown in  FIG. 4 . A head/disk testing apparatus  200  in  FIG. 4  comprises a spin stand  220  and a controlling apparatus  230 . Spin stand  220  comprises a disk rotating apparatus  250 , which holds and rotates disk  240 , and a rotational positioning apparatus  280  and a linear positioning apparatus  290 , which position a head  260  relative to disk  240 . A rotational positioning apparatus  280  is an apparatus for the rotational positioning of an arm  261  that holds head  260 . A linear positioning apparatus  290  is an apparatus for the linear positioning of apparatus  280 . Linear positioning apparatus  290  virtually linearly positions arm  261  that holds head  260 . The coordinates (radius r, skew angle φ) on disk  240  designated by the user are determined by position X of head  260 , which is positioned by linear positioning apparatus  290 , and position θ of head  260 , which is positioned by rotational positioning apparatus  280 .  
         [0038]     Controlling apparatus  230  is an apparatus that controls rotational positioning apparatus  280 , linear positioning apparatus  290 , and disk rotating apparatus  250  of spin stand  220 . Controlling apparatus  230  comprises a CPU  231  and a DSP  232 . Positioning command P 2  is the command for the dynamic positioning of head  260  and is generated by DSP  232  and used for rotational positioning only. DSP  232  generates positioning command P 2  at a high speed independent of CPU  231 . Here, the length of arm  261 , that is, the distance from the center of rotation of rotational positioning apparatus  280  to head  260 , is L. Moreover, the skew angle of head  260  is +. The angle of rotation dθ of rotational positioning apparatus  280  necessary for fine movement by dr of head  260  in the track direction at this time is dθ=sin −1  {dr/(L·cos φ)}. [The value of] dr is very small and therefore, the angle of rotation dθ becomes dθ≈{dr/(L·cos φ)}. Positioning command P 2  should be transmitted at high speed for the high-speed control of rotational positioning apparatus  280 . Thus, it is preferred that positioning command P 2  is the command representing {dr/(L·cos φ)}. Moreover, positioning command P 3  and positioning command P 4  are commands for the static positioning of head  260  and are generated by CPU  231 . Positioning command P 3  is used for rotational positioning. Positioning command P 4  is used for linear positioning. Positioning command P 3  and positioning command P 4  are related to one another and are calculated from coordinates (radius r, skew angle φ) on disk  240  designated by the user. In addition, rotation command R that designates the number of revolutions per unit time of CPU  231  and disk  240  is output. Rotation command R can be output from either CPU  131  or DSP  132 , or it can be output from another apparatus.  
         [0039]     Rotational positioning apparatus  280  receives positioning command P 2  and positioning command P 3  from controlling apparatus  230 . Rotational positioning apparatus  280  comprises a multiplier  281 , an adder  282 , a rotational movement part  283 , a position detector  284 , and a memory  285 . Multiplier  281  is the apparatus that multiplies positioning command P 3  by N and outputs this to adder  282 . Memory  285  is the apparatus for storing positioning command P 2  and outputting pre-stored positioning command P 2  in response to a trigger signal T output from controlling apparatus  230 . Adder  282  adds positioning command P 2  output by memory  285  and positioning command P 3  multiplied by N by multiplier  281  and outputs this command to rotational movement part  283 . The output command of adder  282  becomes positioning command P 1 . The device under test is head  260  held by arm  261 . Position detector  284  detects the position or the amounts of rotation of rotational movement part  283 . Rotational movement part  283  moves the device under test to the place designated by positioning command P 1  while referring to the results detected by position detector  284 .  
         [0040]     Linear positioning apparatus  290  receives positioning command P 4  from controlling apparatus  230 . Linear positioning apparatus  290  moves the device under test to the place designated by positioning command P 4 .  
         [0041]     Disk rotating apparatus  250  receives rotation command R from controlling apparatus  230 . Disk rotating apparatus  250  rotates disk  240  by the number of revolutions per unit time designated by rotation command R. Moreover, disk rotating apparatus  250  outputs a period signal S synchronized with the rotation of disk  240 . For instance, period signal S is an index signal, sector signal, and so forth.  
         [0042]     As described above, the positioning apparatus further comprises a means for generating one positioning command P 1  that is input to rotational movement part  283  from positioning command P 2  and positioning command P 3 , and therefore, controlling apparatus  230  is capable of individually controlling both static positioning and dynamic positioning by rotational movement part  283 . Thus, a control system optimal for dynamic positioning can be made. By means of the present embodiment, rotational positioning apparatus  280  further comprises memory  285  and is adapted such that positioning command P 2  is output from the memory  285  during actual dynamic positioning. DSP  232  should transmit a trigger signal T during actual dynamic positioning. Memory  285  can be adapted such that one positioning command P 2  is output for one trigger signal T, or it can be adapted such that positioning commands P 2  are output in succession and continuously at a pre-determined time intervals for one trigger signal T. In either case, dynamic positioning is hardware-implemented and therefore is very high speed. It should be noted that as long as CPU  231  has sufficient capacity, it can also transmit trigger signals T.  
         [0043]     Moreover, controlling apparatus  230  receives period signals S output from disk rotating apparatus  250 . Head/disk testing apparatus  200  relatively positions head  260  in synchronization with this period signal S and curtails the real time needed for positioning. The details are the same as those for controlling apparatus  130  of the first embodiment. It should be noted that the relative positioning in synchronization with period signal S is realized by changing trigger signal T in synchronization with period signal S. Moreover, memory  285  also operates in synchronization with trigger signal T when memory  285  is positioned in succession and continuously at a pre-determined time interval with respect to one trigger signal T.  
         [0044]     Next, a third embodiment adapted for hardware-implemented control of dynamic positioning is described below.  
         [0045]     A third embodiment of the present invention is a head/disk testing apparatus and a block diagram of this is shown in  FIG. 5 . In  FIG. 5 , a head/disk testing apparatus  300  comprises a spin stand  320  and a controlling apparatus  330 . Spin stand  320  comprises a disk rotating apparatus  350 , which holds and rotates a disk  340 , and a rotational positioning apparatus  380  and a linear positioning apparatus  390 , which position a head  360  relative to disk  340 . Rotational positioning apparatus  380  is an apparatus that rotates and positions an arm  361  holding head  360 . Linear positioning apparatus  390  is an apparatus that linearly positions rotational positioning apparatus  380 . Linear positioning apparatus  390  virtually linearly positions arm  361  that holds head  360 . The coordinates (radius r, skew angle φ) on disk  340  designated by the user are determined from position X of head  360 , which is positioned by linear positioning apparatus  390 , and position θ of head  360 , which is positioned by rotational positioning apparatus  380 .  
         [0046]     Controlling apparatus  330  is an apparatus that controls rotational positioning apparatus  380 , linear positioning apparatus  390 , and disk rotating apparatus  350  of spin stand  320 . Controlling apparatus  330  comprises a CPU  331  and a DSP  332 . A count command C is the command for generating position P 2  for the dynamic positioning of head  360  and is generated by DSP  332 . Here, the length of arm  361 , that is, the distance from the center of rotation of rotational positioning apparatus  380  to head  360 , is L. Moreover, the skew angle of head  360  is +. The angle of rotation dθ of rotational positioning apparatus  380  necessary for fine movements of head  360  by dr in the direction of the track at this time is dθ=sin −1 {dr/(L·cos φ)}. The value of dr is very small and therefore, the angle of rotation dθ becomes dθ≈{dr/(L·cos φ)}. In the end, dθ is a primary function of dr and therefore, positioning command P 2  can be generated by a counter  385 . High-speed operation in comparison to DSP  332  can be expected with counter  385  because of the use of a counter, and so forth. Positioning command P 3  and positioning command P 4  are commands for the static positioning of head  260  and are generated by CPU  331 . Positioning command P 3  is used for the rotational positioning. Positioning command P 4  is used for the linear positioning. Positioning command P 3  and positioning command P 4  are related to one another and are computed from the coordinates (radius r, skew angle φ) on disk  340  designated by the user. Moreover, CPU  331  outputs a rotation command R designating the number of revolutions per unit time of disk  340 . Rotation command R can be output from either DSP  322 , or it can be output from another apparatus.  
         [0047]     Rotational positioning apparatus  380  receives count command C and positioning command P 3  from controlling apparatus  330 . Rotational positioning apparatus  380  comprises a multiplier  381 , an adder  382 , a rotational movement part  383 , a position detector  384 , and counter  385 . Multiplier  381  is the apparatus that multiplies positioning command P 3  by N and outputs this to adder  382 . Counter  385  outputs positioning command P 2  based on count command C in response to a trigger signal T output from controlling apparatus  330 . Count command C includes at least one of the starting value or ending value of the count, or the counter interval. Adder  382  adds positioning command P 2  output by counter  385  and positioning command P 3  multiplied by N by multiplier  381  and outputs this to rotational movement part  383 . The output command of adder  382  becomes positioning command P 1 . The device under test is head  360  held by arm  361 . Position detector  384  detects the position or the amounts of rotation of rotational movement part  383 . Rotational movement part  383  moves the device under test to the place designated by positioning command P 1  while referring to the results detected by position detector  384 .  
         [0048]     Linear positioning apparatus  390  receives positioning command P 4  from controlling apparatus  330 . Linear positioning apparatus  390  moves the device under test to a place designated by positioning command P 4 .  
         [0049]     Disk rotating apparatus  350  receives a rotation command R from controlling apparatus  330 . Disk rotating apparatus  350  turns disk  340  by the number of revolutions per unit time designated by rotation command R. Moreover, disk rotating apparatus  350  outputs a period signal S synchronized with the rotation of disk  340 . For instance, period signal S is an index signal, sector signal, and so forth.  
         [0050]     As described above, the positioning apparatus also comprises a means for generating one positioning command P 1  that is input to rotational movement part  383  from positioning command P 2  and positioning command P 3 , and therefore, controlling apparatus  330  can individually control both static positioning and dynamic positioning by rotational movement part  383 . Thus, a control system optimal for dynamic positioning can be made. By means of the present embodiment, rotational positioning apparatus  280  further comprises counter  385  and is adapted such that positioning command P 2  is output from the counter  385  during actual dynamic positioning. DSP  232  should transmit a trigger signal T during actual dynamic positioning. Counter  385  can also be adapted such that one positioning command P 2  is output for one trigger signal T, or it can be adapted such that positioning commands P 2  are output in succession and continuously at pre-determined time intervals for one trigger signal T. In either case, dynamic positioning is hardware-implemented and therefore is very high-speed. It should be noted that as long as CPU  331  has sufficient capacity, it can also transmit count commands C and trigger signals T.  
         [0051]     Moreover, controlling apparatus  330  receives period signals S output from disk rotating apparatus  350 . Head/disk testing apparatus  300  relatively positions head  360  in synchronization with this period signal S and curtails the real time needed for positioning. The details are the same as for controlling apparatus  130  of the first embodiment. It should be noted that the relative positioning in synchronization with period signal S is realized by changing trigger signal T in synchronization with period signal S. Moreover, counter  385  also operates in synchronization with trigger signal T when counter  385  is positioned in succession and continuously at a pre-determined time interval with respect to one trigger signal T.  
         [0052]     The head/disk testing apparatus in  FIG. 5  can be adapted so that controlling apparatus  330  comprises counter  385  of rotational positioning apparatus  380 . Such a disk testing apparatus is shown in  FIG. 6 . A disk testing apparatus  400  in  FIG. 6  comprises a spin stand  420  and a controlling apparatus  430 . Spin stand  420  comprises linear positioning apparatus  390 , disk rotating apparatus  350 , and a rotational positioning apparatus  480 . Rotational positioning apparatus  480  is rotational positioning apparatus  380  shown in  FIG. 5  minus counter  385 . Moreover, controlling apparatus  430  is controlling apparatus  330  shown in  FIG. 5  also comprising counter  385 . The other structural elements shown in  FIG. 6  are the same as the elements with the same reference number in  FIG. 5 . The detailed description is the same as previously given.  
         [0053]     The present invention is a technology that is useful for a positioning apparatus with which two different positioning operations are possible with one positioning apparatus. Consequently, the results of the present invention are similarly produced even if, in the above-mentioned embodiments, the positioning apparatus comprises a linear movement means such as a piezo actuator with which both dynamic positioning and static positioning are possible in place of a rotational movement part.  
         [0054]     Moreover, the results of the present invention are similarly produced even if the above-mentioned embodiments do not have a multiplier and are adapted so that positioning command P 3  is directly input to the adder.  
         [0055]     Furthermore, the rotational positioning apparatus of the above-mentioned embodiments can also include a position memory means in which the current position is stored so that when the rotational movement means rotates and moves in response to the number of input pulses, positioning command P 1  and the contents of the position memory means are compared and a pulse indicating the difference is output.