The invention is an apparatus for physically exchanging a force with a user in an environment local to the user. A connection element connects to a user's body member and a linkage between the connection element and ground. The linkage includes means for powering at least three independent freedoms of the connection element relative to ground and means for maintaining at least one independent freedom of the connection element relative to ground free of power. Up to three independent freedoms of the connection element may be maintained free of power, and up to five independent freedoms may be powered. Other aspects of the invention include a two actuator counter-balance for controlling a point on a link. The invention also includes apparatus for establishing a virtual, switch, which presents to the user the force and displacement relationship of a spring switch. Another embodiment is a virtual bristled brush, again which presents to the user the force and displacement relationship of such a brush, while also changing the virtual environment to reflect the user's changes in location.

Force reflecting haptic interface

An apparatus (14) for controlling and providing force feedback using an interface device manipulated by a user and connected to a host computer system (12). A microprocessor (26) is provided local to the interface device and reads sensor data from sensors that describes the positioning of a user object moved by the user, such as a joystick. The microprocessor controls actuators (30) to provide forces on the user object. The host computer sends high level host commands to the local microprocessor and the microprocessor independently implements a local reflex process based on the high level command to provide force values to actuators using sensor data and other parameters. A host command protocol includes a variety of different types of host commands and associated command parameters. By providing a relatively small set of high level host commands, the protocol further shifts the computational burden from the host computer to the local microprocessor.

Method and apparatus for controlling force feedback interface systems utilizing a host computer

A method and apparatus for interfacing the motion of a user-manipulable object with an electrical or computer system includes a user object physically contacted by a user. A gimbal mechanism is coupled to the user object, such as a joystick or a medical tool, and provides at least two degrees of freedom to the user object. The gimbal mechanism preferably includes multiple members, at least two of which are formed as a unitary member which provides flex between the selected members. An actuator applies a force along a degree of freedom to the user object in response to electrical signals produced by the computer system. A sensor detects a position of the user object along the degree of freedom and outputs sensor signals to the computer system. Another embodiment includes a host computer system and a local microprocessor, separate from the host computer, for communicating with the host computer and controlling the forces output by the actuators according to a processor subroutine selected in accordance with a host command, sensor signals, and timing information. Another embodiment of the interface apparatus uses voice coil actuators that produce forces in either linear or rotary degrees of freedom using currents applied in a magnetic fields. A friction drive mechanism of the present invention can be coupled between an actuator and a gimbal mechanism. Force from the actuator is transmitted to the gimbal mechanism through frictional contact of members of the friction drive mechanism.

Computer interface apparatus including linkage having flex

An apparatus for interfacing the movement of a shaft with a computer includes a support, a gimbal mechanism having two degrees of freedom, and three electromechanical transducers When a shaft is engaged with the gimbal mechanism, it can move with three degrees of freedom in a spherical coordinate space, where each degree of freedom is sensed by one of the three transducers A fourth transducer can be used to sense rotation of the shaft around an axis The method includes the steps of defining an origin in 3-dimensional space, physically constraining a shaft in the 3-dimensional space such that a portion of the shaft always intersects the origin and such that a portion of the shaft extending beyond the origin defines a radius in a spherical coordinate system, transducing a first electrical signal related to a first angular coordinate of the radius with a first transducer, transducing a second electrical signal related to a second angular coordinate with a second transducer, transducing a third electrical signal related to the length of the radius with a third transducer, and coupling the transducers to a computer

Method and apparatus for providing force feedback to the user of an interactive computer simulation

A method and apparatus for providing safe and low-cost force feedback peripherals for consumer applications. A device microprocessor (26) local to an interface device (14) is coupled to the host (12) by a first interface bus (24). The microprocessor receives host commands from the host computer on the first interface bus, such as an RS-232 interface, and commands an actuator (30) to apply a force to a user object (22), such as a joystick, in response to host commands. A sensor (28) detects positions of the user object and outputs signals to the host on a second interface bus (25), such as a PC game port bus, separate from the firt bus. A safety switch (41) of the present invention disables the actuator when the interface device is not in use and enables the actuator when an amount of weight over a predetermined amount is placed on the joystick created by a user grasping the joystick.

Safe and low cost computer peripherals with force feedback for consumer applications

The invention contemplates an articulating head having bearings of reproducible travel behavior, for precision angular displacment of a mounted probe-pin, about each of two orthogonal component axes of rotation. The precision of angular displacement relies upon high-resolution angle encoders for reading the instantaneous angle for each of these component axes of rotation and for reporting the same to the computer of a coordinate-measuring machine. Active position-control circuits use the angle encoders for controlling drive about the respective component axes of rotation, all in conjunction with a given program of measurements by the coordinate-measuring machine. A probe holder mounted to the articulating head can be oriented to any desired angular aspect with respect to the workpiece feature to be measured or scanned, and measurements can be made solely by controleld actuation via one or both drives on the respective axes of the articulating head, i.e., while rectilineal drives of the coordinate-measuring machine are arrested. Alignment and travel behavior of the articulation axes are determined by a calibration program and are used for correction of measurement values read from the angle-encoders of the articulating head.

Articulating head for a coordinate-measuring instrument

The invention is directed to a magazine for an apparatus such as a coordinate measuring apparatus. Measuring probes are held in their magazine locations by magnetic forces. Each magazine location is provided with one or more permanent magnets. The holding force of the permanent magnets is neutralized by an individual electromagnet on that magazine location which is involved in an exchange operation. In this way, the measuring probe being held can be easily removed. The magazine can also be for an apparatus such as a machine tool in which case work tools are held at the magazine locations.

Magazine for coordinate measuring apparatus

A bearing arrangement has fluid pressure bearings which permit an especially stiff support and is therefore especially well suited for high precision machines such as coordinate measuring apparatus. The bearing arrangement includes at least two fluid pressure bearings ( 12, 13, 14, 15, 16, 17 ) having a membrane formed as a support end. The membrane is concavely deformed by the bearing pressure. The bearing arrangement also includes a rigidly configured bearing base body which is supported on the two fluid pressure bearings. The rigid support is achieved in that at least one of the fluid pressure bearings includes a bearing housing ( 12 a , 12 b ; 13 a , 13 b ; 14 a , 14 b ) which is configured as one piece and in that the bearing base body ( 6 ) is operatively connected directly to the bearing housing ( 12 a , 12 b ; 13 a , 13 b ; 14 a , 14 b ). The bearing housing includes at least the membrane.

Fluid pressure bearing

Truncated pyramid mounting configurations and relationships are disclosed as inherently and reproducibly determining an accurate zero-position as between a probe head and a probe pin that is deflectably carried by the probe head. And the same principle of accurately determining zero position is also described in application to the automated releasable chucking of interchangeable probe pins and/or of an auxiliary probe head, as to the installed probe head of a coordinate-measuring machine. In one described case of truncated triangular pyramid mountings, the zero position is determined by concurrent engagement of six seating points which are distributed radially and axially with respect to the common central longitudinal axis of the involved geometric pyramids. The mounting configurations have high torsional rigidity and a relatively large region within which self-centering to the zero position is achieved. Furthermore, thise mounting configurations are characterized by an azimuth-angle distribution of relatively uniform force in opposition to a probe-pin or the like deflection, and associated lift-off, from the fully seated zero position.

Probe head mount for a deflectable probe or the like

Die Dreh-Schwenk-Einrichtung besitzt Drehlager mit reproduzierbarem Laufverhalten in den Achsen sowie hochauflosende Winkelencoder zur Ruckmeldung der eingestellten Dreh- bzw. Schwenkwinkel an den Rechner des Koordinatenmesgerates. The articulating device has pivot bearing with a reproducible migration behavior in the axes and high-resolution optical encoder to indicate the set rotation or pivot angle of the computer of the coordinate. Uber aktive Positionsregelkreise, durch die der Winkelencoder und der Antrieb der jeweiligen Achse in die Steuerung des Koordinatenmesgerates eingebunden sind, last sich der an der Dreh- Schwenk-Einrichtung befestigte Tastkopf in beliebige Winkelstellungen ausrichten bzw. das zu vermessende Werkstuck aktiv bei stillgesetzten Antrieben des Koordinatenmesgerates allein mit Hilfe der Dreh-Schwenk- Einrichtung antasten. On active position control loops through which the angle encoder and the drive of each axis are involved in the control of the coordinate, the fixed to the trunnion device probe into any angular positions can be aligned or the workpiece to be measured active in the stopped drives of the coordinate Only with the help of articulating touch device. Ausrichtung und Laufverhalten der Dreh-und Schwenkachse werden uber ein Kalibrierprogramm ermittelt und zur Korrektur der von den Encodern der Dreh-Schwenk-Einrichtung gelieferten Meswerte verwendet. Orientation and transport behavior of rotating and swiveling axis are determined using a calibration program and used to correct the measured values ​​supplied by the encoders of the articulating device.

Dieter Kaufmann

Papers

Articulating head for a coordinate-measuring instrument

Magazine for coordinate measuring apparatus

Fluid pressure bearing

Probe head mount for a deflectable probe or the like

Rotation-deflection arrangement for the feeler heads of coordinate-measuring devices