A method for controlling a surgical device is provided. The method includes manipulating the surgical device to perform a procedure on a patient; determining whether a relationship between an anatomy of the patient and a position, an orientation, a velocity, and/or an acceleration of a surgical tool of the surgical device corresponds to a desired relationship between the anatomy and the position, the orientation, the velocity, and/or the acceleration of the surgical tool; and imposing a constraint on the surgical device if the relationship does not correspond to the desired relationship and/or a detection device is unable to detect a position of the anatomy and/or the position of the surgical tool.

Method and apparatus for controlling a haptic device

There are provided a magnetoresistance effect element, a magnetic head, a magnetic head assembly and a magnetic recording system, which have high sensitivity and high reliability. The magnetoresistance effect element has two ferromagnetic layers, a non-magnetic layer provided between the ferromagnetic layers, and a layer containing an oxide or nitride as a principal component, wherein the layer containing the oxide or nitride as the principal component contains a magnetic transition metal element which does not bond to oxygen and nitrogen and which is at least one of Co, Fe and Ni.

Magnetoresistance effect element

A motor driving apparatus comprises an inverter circuit for converting an output voltage of a power supply into a three-phase AC and outputting the same to the brushless motor; a rotor position estimation unit for estimating a rotor position of the brushless motor; and an inverter control unit for controlling the inverter circuit so that the brushless motor is driven by a current based on the estimated rotor position. The inverter control unit determines an advance angle of the current supplied to the brushless motor with respect to the estimated rotor position so as to minimize a deviation between a command rpm and an actual rpm. Therefore, it is possible to perform stable weak field control for the brushless motor, independently from the input voltage of the inverter circuit, without using predetermined control variables such as table values.

Motor driving apparatus

A high-performance cache is disclosed. The cache is designed for time- and space-efficiency for a diverse range of information objects. Information objects are stored in portions of a non-volatile storage device called arenas, which are contiguous regions from which space is allocated in parallel. Objects are substantially contiguously allocated within an arena and are mapped by name keys and content-based object keys to a tag table, an open directory, and a directory table. The tag table is indexed by the name keys, and stores references to sets in the directory table. The tag table is compact and therefore can be stored in fast main memory, facilitating rapid lookups. The directory table is organized so that at least a frequently-accessed portion of it also usually resides in fast main memory, which further speeds lookups. The tag and directory tables are organized to quickly determine non-presence of objects. Large objects are chunked into fragments, which are chained using a forward functional-iteration mechanism, to prevent the need for mutating existing on-disk data structures. Garbage collection periodically moves objects within an arena or to other arenas. Additionally, for a plurality of counters, the following is computed: (1) the sum of values stored in the counters, and (2) the maximum value that can be represented by the coimters. Each of the counters are decremented when the sum is greater than half of the maximum value. Each of the counters is associated with an information object, which is deleted when a counter is decremented to zero.

Maintaining counters for high performance object cache

The novel method of fabrication of the present invention allows conventional or other lithography machines to produce very small well defined thin film structures or elements. The present invention provides a method to produce well defined elements, including sensors or read heads well below 0.1 microns, even when using conventional photolithography processes. The presently preferred method for forming the thin film device of the present invention includes depositing and exposing resist so as to define a first thin resist stripe. A portion of the resist is removed leaving a first thin strip covering a portion of the first material layer. The uncovered portion of the first material layer is removed to leave a first material strip. A second resist layer is deposited and exposed so as to define a second thin stripe intersecting the first material strip. A portion of the second resist layer is removed so as to leave a second thin strip of resist covering a portion of the first material strip. The uncovered portion of the first material strip is removed leaving the small thin film element. Typically, the second thin strip of resist is formed perpendicular to the first material strip thereby providing a very small thin film element having planar surfaces with precisely defined squared corners. A feature of the present invention is that it provides a small magneto-resistive read head having a planar sensing surface with abutting planar side walls orthogonal to the sensing surface thereby providing a well defined small sensor element.

Method of fabricating an improved thin film device having a small element with well defined corners

A control process and apparatus for positioning an electric motor provided with a rotation angle detector at a designated position positively at a high speed without being accompanied with hunting notwithstanding variation in the motor current and inertia of a load The control process activated upon starting of the motor and ending at the stoppage of the motor at the designated position includes a first control region in which acceleration of the motor having been started is detected and subsequently a constant speed operation of the motor is effected at a maximum speed A deceleration initiating time point is determined in dependence on the acceleration A second control region is provided in which the motor is decelerated in accordance with a deceleration pattern determined in dependence on a rotation angle extending between a position corresponding to the deceleration initiating time point and the commanded stop position, and motor torque and inertia of load is detected at the deceleration initiating time point During a third control region the motor is progressively decelerated by reducing correspondingly the gain of voltage (current) applied to the motor when the motor position approaches to the commanded stop position The control process also includes a fourth control region in which, when the motor stops short of or beyond the commanded position, the duty ratio of voltage applied to the motor is progressively increased to thereby re-start the motor toward the commanded position, and a fifth control region in which the motor is held at the commanded stop position

Method and apparatus for position control of an electric motor

A method and apparatus for controlling the angular position of a motor by controlling the revolution of the motor in response to a given positioning command value commanding a predetermined angular position of the motor shaft so as to stop the motor shaft at the predetermined angular position, wherein the acceleration of the motor being accelerated in the initial acceleration stage of the motor position control operation is calculated, and on the basis of the calculated acceleration and a commanded maximum velocity, the remainder angular distance between the deceleration starting angular position and the desired angular position of the motor and the deceleration command value in the deceleration stage are calculated so as to control the deceleration of the motor on the basis of the calculated values.

Method for controlling angular position and apparatus therefor

An encoder with a position detecting device is disclosed which is applicable to a brushless motor or the like, and includes a rotating body provided on a surface thereof with a magnetic material and magnetoresistive elements disposed opposite to and in close proximity to said magnetic material. The rotating body is provided with an encoding track in which a magnetic signal has been recorded in a predetermined direction of magnetization, and a position detecting track in which a magnetic signal has been recorded in a direction of magnetization intersecting with the predetermined direction of magnetization. The magnetoresistive elements are formed on an insulating substrate and face the tracks. Further, the magnetoresistive elements are arranged side by side in a radial direction of the rotating body and each of the magnetoresistive elements is placed so that the magnetoresistive element intersects the direction of magnetization in a track facing the magnetoresistive element, to make small the magnetoresistive element supporting substrate, thereby making the whole of the encoder small in size, and to prevent magnetic interference between the encoding track and position detecting track, thereby enhancing the performance of the encoder with the position detecting device.

Device for detecting the relative and absolute position of a moving body

Disclosed is a magnetic rotary encoder used in combination with a rotary body having plural pieces of magnetic information recorded on at least one circumferentially running track. The rotary encoder comprises a substrate having a surface disposed opposite to the rotary body and at least one magnetoresistive element formed on the surface of the substrate. The magnetoresistive element is formed on the substrate surface as an integral pattern including at least two portions extending substantially in the radial direction of the rotary body in a relation opposite to the magnetic information recorded portion of the rotary body, two lead connection terminal portions formed at the outer ends of the radially extending portions respectively, and a circumferentially extending portion interconnecting the radially extending portions at their ends, so as to form a single electrical signal path which passes both of the radially extending portions and terminates in the two lead connection terminal portions. These lead connection terminal portions are disposed outside of the outer peripheral edge of the rotary body.

Magnetic rotary encoder

The invention discloses a movement detecting device for detecting the movement state of a moving body such as a rotating body, in which a magnetic recording medium on which N and S magnetic poles are alternately recorded at a constant interval is fixed symmetrically with respect to a rotary shaft of a rotating body whose rotation state is to be detected, and an MR element comprising magnet-resistive elements is mounted at a fixed position relative to the magnetic recording medium so that the rotation state of the rotating body can be detected from variation of the values of resistance of the magnet-resistive elements caused by the rotation of the body. N and S poles are recorded on the magnetic recording medium with a small pole pitch P. The magnet-resistive elements are formed to have a width sufficiently smaller than the pole pitch. The magnet-resistive elements constitute a first group and a second group, the magnet-resistive elements of each group being disposed with an interval equal to the pole pitch or half the pole pitch. The magnet-resistive elements are disposed in such a manner that the interval between the groups is deviated from the pole pitch, whereby a circuit comprising these magnet-resistive elements can detect the rotation of the rotating body.

Hiroshi Hayashida

Papers

Method and apparatus for position control of an electric motor

Method for controlling angular position and apparatus therefor

Device for detecting the relative and absolute position of a moving body

Magnetic rotary encoder

Magneto resistive sensor for detecting movement of a rotating body