CN101327596A - Wearing type finger tip passive-force sense-reproducing device - Google Patents

Abstract

The present invention discloses a worn finger-tip passive force feedback device used to realize the control of a telerobot and a virtual reality application. The worn finger-tip passive force feedback device comprises a fixing strap, a force sensor, a first link rod, a passive force generator, a second link rod, a first end plate and a second end plate and adopts a magneto-rheological Damper or a electro-rheological damper as the passive force generator. A series-double-link-rod mechanism is adopted to transmit damping force to the tip of a finger, so that counterforce can be applied on the finger, and as a result, the finger can feel the effect of the force. Adopting the force feedback control technology, the worn finger-tip passive force feedback device utilizes the force sensor to measure the interaction force between the tip of the finger and the ends of the link rods, and the interaction force serves as a force feedback signal to quantitively control the damping force generated by the damper. The worn finger-tip passive force feedback device has the advantages of simple structure, accurate control, safe and reliable operation, low cost, etc.

Description

Wearing type finger tip passive-force sense-reproducing device

Technical field

The present invention relates to a kind of human-computer interface device of realizing teleoperation robot control, relate in particular to a kind of wearing type finger tip passive-force sense-reproducing device of virtual reality applications.

Background technology

Along with the extensive use of interactive teleoperation robot, the human-computer interface device that needs are a large amount of with power feel feedback effect.The manual device of data glove and robot is the human-computer interface device of two kinds of common teleoperation robots, the manual device of robot is an effectively human-computer interface device of realizing teleoperation robot control, but hand controller comparatively speaking, complicated in mechanical structure, on fixing platform, operate, limited the scope of activities of hand, and after the long-time operation, the operator can feel tired.Traditional data glove generally can both be measured the corner of finger-joint and the corner between finger comparatively exactly, and according to measurement data the actions such as extracting of long-range manipulator is controlled, but does not have power feel feedback function.Force feedback data gloves is as a kind of human-computer interface device, it controls the motion of the virtual machine hand tracking staff in manipulator or the virtual reality on the one hand as control instruction by the positional information of measure operator hand, on the other hand, power feel and tactile data that robot is fed back convert power or the moment that directly acts on staff to, make the operator be created in the power feel/sense of touch telepresenc effect that machine far away is manually done " on the spot in person " of scene or virtual robot working site, thereby realize control to robot band sensation, perhaps in virtual environment, produce the real impression that touches, and it has overcome the hand controller complicated in mechanical structure, the scope of activities of hand is little not to have the shortcoming of force feedback function with the traditional data gloves, has the prospect of using widely.

But the cost of force feedback data gloves is higher, and force feedback can be divided into active and passive-type, and the device for force feedback of force feedback data gloves can be contained on palm and the arm, generally is fixed on arm with one group of frame for movement, drives with micro machine; Also have by one group of pneumatic or hydraulic means to be fixed on the palm, stop with gas or liquid and drive.Be installed on the arm device for force feedback because of its on arm, so hand is free to open and hold with a firm grip, but because mechanism is comparatively complicated, make this device for force feedback weight bigger, put on this force feedback data gloves long-time operation defensive position capacity and feel tired, and control circuit is also comparatively complicated, and control circuit and drive motors also will be placed on the workbench.The size that is installed in the device for force feedback on the palm can be done a little bit smallerly, so weight is lighter, but owing to device is installed on the palm, the opening and closing of hand are affected, and palm can not be held with a firm grip fully, in addition, no matter be pneumatic or hydraulic pressure, all pressure source to be arranged, control circuit is more complicated also.

Summary of the invention

The invention provides a kind of simple and light and do not need the wearing type finger tip passive-force sense-reproducing device of data glove.

The present invention adopts following technical scheme:

A kind of wearing type finger tip passive-force sense-reproducing device that is used to realize teleoperation robot control and virtual reality applications, comprise first connecting rod and second connecting rod, between first connecting rod and second connecting rod, be provided with the passive forces generator, the passive forces generator comprises shell, be filled with rheology liquid in the enclosure, be provided with damping fin and driving source in the enclosure, on damping fin, be connected with output shaft, one end of described first connecting rod is connected with the shell of passive forces generator, one end of described second connecting rod is connected with the output shaft of passive forces generator, the other end at first connecting rod is rotatably connected to first end plate, on first end plate, be provided with the power sensor, be rotatably connected to second end plate at the other end of second connecting rod.

Driving source in the described passive forces generator can further adopt one of following scheme:

(1) second electrode and first electrode on the driving source in the passive forces generator comprises first electrode and is located at damping fin are faced mutually with second electrode, and the rheology liquid in the described passive forces generator is ER fluid.

(2) driving source in the passive forces generator comprises first coil and second coil that is located on the outer casing inner wall, and the rheology liquid in the described passive forces generator is magnetic flow liquid.

Compared with prior art, the present invention has following advantage:

1, whole device of the present invention is the Wearable structure, simple in structure, mainly be to connect firmly by an end of first connecting rod shell with the passive forces generator, one end of second connecting rod constitutes rotational structure with the output shaft hinge connection of passive forces generator, increased the free degree of hand exercise, hand is moved in comfortable reasonable range, meet the characteristics of motion of hand more, and can embody the compliance of hand injected organism tissue.In existing device for force feedback, wherein CyberGrasp is by comparatively complicated mechanism is installed on the back of the hand, fix a fine rule at each finger, make the sensation of finger generation power with a micromachine pulls wire, because of its complicated in mechanical structure, weight are bigger, make produce after operator's long-time operation tired, in addition, interface circuit and drive motors will be installed in the control box of a distant place in addition, thereby the scope of activities of frictional force increase and hand also is restricted.Rutgers Master II force feedback data gloves is to form by one group of mechanism that is installed on the palm, and weight is lighter, and frictional force is also less, but because it is pneumatic, so extra high-pressure air source must be provided, its control device is more complicated also.And based on the device for force feedback of data glove, its critical piece is a piston of driving cannelure, though simple in structure, because the freedom of motion of piston is restricted, hand can only move in one direction, and hand exercise is single limited.

2, adopt the passive-force sense reproducting method, have safe, the advantage that volume is little.

3, adopt force sensor measuring finger tip power, the measurement feedback of pointing end and interlinking lever end interaction force is constituted the power closed-loop control to controller, the accuracy of capable control and stability are increased.

To sum up, finger tip passive-force sense-reproducing device of the present invention has simple in structure, precise control, and cost is low and be easy to realize and advantage safe and reliable to operation.

Description of drawings

Fig. 1 is the schematic perspective view of the wearing type finger tip passive-force sense-reproducing device of the embodiment of the invention.

Fig. 2 is the positive planar structure schematic diagram of the embodiment of the invention.

Fig. 3 is the vertical view of the embodiment of the invention.

Fig. 4 is the structural representation of the MR damper of the embodiment of the invention.

Fig. 5 is the structural representation of the electro-rheological fluid damper of the embodiment of the invention.

Fig. 6 is the structured flowchart of the embodiment of the invention.

The specific embodiment

Hereinafter in conjunction with the accompanying drawings and specific embodiment wearing type finger tip passive-force sense-reproducing device of the present invention is described in detail.

With reference to Fig. 1, Fig. 2, Fig. 3, a kind of wearing type finger tip passive-force sense-reproducing device that is used to realize teleoperation robot control and virtual reality applications, comprise first connecting rod 2 and second connecting rod 4, between first connecting rod 2 and second connecting rod 4, be provided with passive forces generator 3, passive forces generator 3 comprises shell, be filled with rheology liquid in the enclosure, be provided with damping fin and driving source in the enclosure, on damping fin, be connected with output shaft, one end of described first connecting rod 2 is connected with the shell of passive forces generator 3, one end of described second connecting rod 4 is connected with the output shaft of passive forces generator 3, the other end at first connecting rod 2 is rotatably connected to first end plate 1, is provided with power sensor 7, the first end plates 1 and is connected with fixed band 8 on first end plate 1, being rotatably connected to second end plate, 6, the second end plates 6 at the other end of second connecting rod 4 is connected with fixed band 5.

Be embodiment 1 below:

In the present embodiment, with reference to passive forces generator 3 shown in Figure 4 is electro-rheological fluid damper, second electrode 311 on driving source wherein comprises first electrode 312 and is located at damping fin and first electrode 312 are faced mutually with second electrode 311, and the rheology liquid in the described passive forces generator 3 is ER fluid 313.Current liquid 313 is a kind of liquid intellectual materials, and when electric field existed, violent variation took place for its rheological properties such as viscosity.Current liquid is an aaerosol solution, is evenly dispersed in base soln (continuous phase) lining by solids (decentralized photo), and solids and base soln all are insulating properties dielectrics preferably.The diameter of solids 1/10th to one of percentage micron, electric rheological effect is called the Winslow effect sometimes, be to produce by the polarization of dispersed phase particles and continuous phase particle, when electric field exists, dispersed phase particles is because polarization motion, on direction of an electric field, form chain, when electric-field intensity continues to increase, it is big that this chain will become, this just may cause viscosity, shearing force and other characteristic of current liquid to change, become semifluid (having certain viscoelasticity) as gelinite by original fluid state, even become solid.When removing electric field, current liquid reverts to original fluid.If the external diameter of damping fin 315 is r, the spacing between second electrode 311 on first electrode 312 and the damping fin 315 is h, and then the shear stress of output shaft 314 can calculate according to following formula:

τ＝τ _c+η·v (1)

(1) in the formula, τ _cBe yield stress, η is the plastic viscosity of ER fluid, and v is a shear rate.The rotating speed of output shaft is n, and then shear rate is:

$v=\frac{d\left(\mathrm{r\ωx}\right)}{\mathrm{dx}}=\frac{r}{h}n---\left(2\right)$

So, the moment T that produces owing to electric rheological effect is:

$T={\&Integral;}_0^{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="A20081002248300091.png,A20081002248300101.png"\; state="\{\{state\}\}">r</figure-callout>}}2\mathrm{\&pi;\&tau;}{\mathrm{<figure-callout\; id="2"\; label="x"\; filenames="A20081002248300091.png,A20081002248300101.png"\; state="\{\{state\}\}">x</figure-callout>}}^2\mathrm{dx}=\frac{2\mathrm{\&pi;}{\mathrm{\&tau;}}_{\mathrm{<figure-callout\; id="3"\; label="c\; r"\; filenames="A20081002248300091.png,A20081002248300102.png"\; state="\{\{state\}\}">c</figure-callout>}}{r}^{}{}^3}{3}+\frac{\mathrm{\&pi;\&eta;}{\mathrm{nr}}^4}{2h}---\left(3\right)$

According to the principle of electric rheological effect, yield stress τ _cCan be expressed as:

${\mathrm{\&tau;}}_c=K_c\frac{E^2}{h^2}---\left(4\right)$

K _cBe yield stress electric field coefficient.The output torque of output shaft then;

$T=\frac{2\mathrm{\&pi;}{K}_c{E}^2{\mathrm{<figure-callout\; id="3"\; label="r"\; filenames="A20081002248300091.png,A20081002248300102.png"\; state="\{\{state\}\}">r</figure-callout>}}^3}{{3\mathrm{<figure-callout\; id="2"\; label="h"\; filenames="A20081002248300091.png,A20081002248300101.png"\; state="\{\{state\}\}">h</figure-callout>}}^2}+\frac{\mathrm{\&pi;\&eta;n}{r}^4}{2h}---\left(5\right)$

Because the speed of finger activity is very low, thus second in (5) formula can ignore, promptly

$T=\frac{2\mathrm{\&pi;}{K}_c{E}^2{\mathrm{<figure-callout\; id="3"\; label="r"\; filenames="A20081002248300091.png,A20081002248300102.png"\; state="\{\{state\}\}">r</figure-callout>}}^3}{{2h}^2}---\left(6\right)$

From (6) formula as can be known, output torque T is directly proportional with 2 powers of applied voltage E.Therefore we just can control the variation of damping quickly and accurately by the size of control applied voltage E.

The operation principle of the wearing type finger tip passive-force sense feedback device of employing electro-rheological fluid damper is as follows: the structure of wearing type finger tip passive-force sense-reproducing device is with reference to Fig. 1, Fig. 2, Fig. 3.When not having electric field to be added between two electrodes, the device flexibility is good, and articulations digitorum manus can freely be stretched song.When electric field was added between two electrodes, variation had taken place in the rheologic behavio(u)r of current liquid, and viscosity improves, and produce anti-shearing yield stress, thus hinder link motion, produce a passive masterpiece and be used on the finger, make doigte arrive the power effect, finger is stretched song and is obstructed.When electric field reached certain critical value, current liquid became solid-state, has the feature of solid, and finger is stretched song and is obstructed fully.Simultaneously, being fixed on power sensor on first end plate detects the active force that finger is subjected to and feeds back to control system, by control circuit the proportional voltage that converts to of force information is loaded into electro-rheological fluid damper, the rheologic behavio(u)r of current liquid is changed, increase or reduce viscosity coefficient, crooked thereby the control finger continues.With reference to Fig. 6, the wearing type finger tip passive-force sense feedback device adopts proportion control, the damping force f that the passive forces generator produces _dThe power f that goes out with force sensor measuring compares, and designs suitable control ratio P value to reach the purpose of accurate control.

Be embodiment 2 below:

In the present embodiment, be MR damper with reference to passive forces generator 3 shown in Figure 5, driving source wherein comprises first coil 325 and second coil 326 that is located on shell 322 inwalls, the rheology liquid in the described passive forces generator 3 is magnetic flow liquid 321.Current liquid 321 is a kind of liquid intellectual materials, can produce different shearing forces by the excitatory size of control.Magnetic flow liquid is that saturation induction density is very high and suspension that the very little soft magnetism microparticulate of coercivity forms in non-magnetic oil.Under externally-applied magnetic field, its fluidic structures and performance meeting instantaneous variation, the apparent coefficient of viscosity increases several magnitude, even show class solid performance, the yield strength of its generation changes with the variation of externally-applied magnetic field, after externally-applied magnetic field was removed, the structure and the performance of magnetic flow liquid were restored rapidly in several milliseconds.The exciting curent size of control coil just can be controlled the shear yield stress of magnetic flow liquid, and then control output torque.The shear stress of output shaft 323 can calculate according to following formula:

$\mathrm{\&tau;}={\mathrm{\&tau;}}_y\left(H\right)\mathrm{sgn}\left(\frac{\mathrm{du}}{\mathrm{dy}}\right)+\mathrm{\&eta;}\&CenterDot;\left(\frac{\mathrm{du}}{\mathrm{dy}}\right)---\left(7\right)$

(7) in the formula, τ is the shear stress of magnetic flow liquid; τ _v(H) be the surrender shear stress of magnetic flow liquid; η is the dynamic viscosity of fluid; Be velocity gradient, first on equal sign the right is called a coulomb shear stress, and second is called the viscous shear stress.τ _v(H) relevant with magnetic field intensity, change along with the change of magnetic field intensity, so the surrender shear stress can be controlled by magnetic field.

The operation principle of the wearing type finger tip passive-force sense feedback device of employing MR damper is as follows: the structure of wearing type finger tip passive-force sense-reproducing device is with reference to Fig. 1, Fig. 2, Fig. 3.When not having electric field to be added on the magnetic rheological liquid coil on every side, the device flexibility is good, and articulations digitorum manus can freely be stretched song.In the time of on the coil around electric field is added to magnetic rheological liquid, variation has taken place in the rheologic behavio(u)r of magnetic rheological liquid, and viscosity improves, and produce anti-shearing yield stress, thus hinder link motion, produce a passive masterpiece and be used on the finger, make doigte arrive the power effect, finger is stretched song and is obstructed.When electric field reached certain critical value, magnetic rheological liquid became solid-state, has the feature of solid, and finger is stretched song and is obstructed fully.Simultaneously, being fixed on power sensor on first end plate detects the active force that finger is subjected to and feeds back to control system, by control circuit the proportional voltage that converts to of force information is loaded into MR damper, the rheologic behavio(u)r of magnetic rheological liquid is changed, increase or reduce viscosity coefficient, crooked thereby the control finger continues.With reference to Fig. 6, the wearing type finger tip passive-force sense feedback device adopts proportion control, the damping force f that the passive forces generator produces _dThe power f that goes out with force sensor measuring compares, and designs suitable control ratio P value to reach the purpose of accurate control.

Claims (3)

1, a kind of wearing type finger tip passive-force sense-reproducing device that is used to realize teleoperation robot control and virtual reality applications, it is characterized in that: comprise first connecting rod (2) and second connecting rod (4), between first connecting rod (2) and second connecting rod (4), be provided with passive forces generator (3), passive forces generator (3) comprises shell, be filled with rheology liquid in the enclosure, be provided with damping fin and driving source in the enclosure, on damping fin, be connected with output shaft, one end of described first connecting rod (2) is connected with the shell of passive forces generator (3), one end of described second connecting rod (4) is connected with the output shaft of passive forces generator (3), the other end at first connecting rod (2) is rotatably connected to first end plate (1), on first end plate (1), be provided with power sensor (7), be rotatably connected to second end plate (6) at the other end of second connecting rod (4).

2, wearing type finger tip passive-force sense-reproducing device according to claim 1, it is characterized in that driving source in the passive forces generator (3) second electrode (311) and first electrode (312) on comprising first electrode (312) and being located at damping fin face mutually with second electrode (311), the rheology liquid in the described passive forces generator (3) is ER fluid (313).

3, wearing type finger tip passive-force sense-reproducing device according to claim 1, it is characterized in that the driving source in the passive forces generator (3) comprises first coil (325) and second coil (326) that is located on shell (322) inwall, the rheology liquid in the described passive forces generator (3) is magnetic flow liquid (321).

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