Active joystick with optical position sensor

a technology of optical position sensor and joystick, which is applied in the direction of mechanical control devices, manual control with single controlling member, sports apparatus, etc., can solve the problems of not being able to show that a workspace of this magnitude is really needed, and designing high acceleration devices over large workspaces is a non-trivial task requiring expensive actuators, transmissions and joints, etc., and achieves a larger rattle sp and higher forces

Inactive Publication Date: 2001-11-08
SALCUDEAN SEPTIMIU E +1
View PDF0 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0014] Broadly the present invention relates to a basic actuator structure comprising a stator formed by a pair of opposed magnets defining a gap therebetween a floater formed by a flat actuator coil interposed in the gap. The gap has a width d and the flat coil has a thickness d.sub.c and the ratio of coil thickness d.sub.c to gap width d is between 1 / 3 and 1 / 2 (d.sub.c / d=1 / 3 to 1 / 2) to provide a larger rattle space without sacrificing force applied between the coil and magnets.
[0015] It is a further object of the present invention to provide a new actuation system geometry, providing a well conditioned transformation from actuator currents to resultant forces and torques, to produce uniformly distributed commanded forces and torques,
[0018] It is yet another objective of the present invention to provide a new optical position sensor that is significantly less expensive than sensing systems used in other maglev devices, even though it provides similar sensing volume and resolution.

Problems solved by technology

Although most reported designs have translational workspaces that exceed a cube with 10 cm sides, it has not been shown that a workspace of this magnitude is really needed.
Furthermore, designing high acceleration devices over large workspaces is a non-trivial task requiring expensive actuators, transmissions and joints.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Active joystick with optical position sensor
  • Active joystick with optical position sensor
  • Active joystick with optical position sensor

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0039] Basic Actuator Structure

[0040] The basic actuator structure 10 as shown in FIGS. 1 and 1A is composed of a flat coil 100 interposed in a magnetic assembly 12 between a pair of cooperating magnet assemblies 110 and 120. Each magnet assembly is composed of a pair of magnets 112 and 114 mounted on and coupled together via magnetically permeable (soft iron, for example) return plates 116 to generate a magnetic field as indicated by the arrows B. The field interacts with the coil current as indicated by the arrows I to generate a Lorentz force as indicated by the vector F. For clarity, the coil 100 is shown translated upwards along the direction of its force F, but its nominal position is in the middle of the magnetic assembly.

[0041] In the system illustrated in FIG. 1 the various dimensions of the elements have been designated as follows; the magnet width w.sub.m, the magnet thickness t.sub.m, the magnet length l.sub.m, the magnet spacing g.sub.m, the coil 100 thickness d.sub.c, ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

A joystick composed of a stator formed by an outer cage forming an inner cubic compartment containing an inner cube oriented with its wall spaced from and substantially parallel corresponding wall of the compartment. Opposed magnets are position in cooperating relationship on opposed walls of the compartment and cube and define a gap therebetween. A floater formed by a plurality of flat actuating coils, one positioned in each gap and each thinner than the width of the gap in which it is received. Preferably the ratio of coil thickness to gap width is at least 1:3. Preferably an optical position sensor is used to monitor the relative position of the flotor and stator and is composed of at least one linear light position sensor mounted on one of the stator and flotor and a plurality of planar light beams arranged at an angle to each other on the other of the stator and flotor and directed to the linear light position sensor(s) so that the light beams traverse the linear light position sensor(s).

Description

[0001] The invention relates to a motion device formed by a flat actuating coil (e.g. a Lorentz voice coil) positioned between magnets having improved rattle space, a joystick with improved geometry incorporating the motion device and to an optical position sensing systemBACKGROUND TO THE PRESENT INVENTION[0002] A number of active joysticks or haptic interfaces (interfaces capable of generating kinesthetic and tactile feedback to the user) have been proposed for virtual environments and teleoperation systems.[0003] Attention is directed to Stocco, L., Salcudean, S. E., "A coarse-fine approach to force-reflecting hand-controller design," in Proc. 1996 IEEE Intl. Conf. Rob. Aut. Minneapolis, MN, pp..about.404-410, Apr. 22-28, 1996. for a detailed survey, and to Hayward, V., Astley, O. R., "Performance measures for haptic interfaces," in Proc. ISRR, p..about.(12 pages), 1995. for performance measures.[0004] The need for high acceleration in haptic computer-user interfaces has been demo...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & AuthorityApplications(United States)
IPC IPC(8): G05G9/047G06F3/00G06F3/01G06F3/038G06F3/042
CPCG05G9/047G05G2009/04759G06F3/011G06F3/0346G06F3/0383G06F3/0421
InventorSALCUDEAN, SEPTIMIU E.PARKER, NIALL R.
OwnerSALCUDEAN SEPTIMIU E