CN103235649A - Three-dimensional wireless input device based on micro-electro-mechanical systems (MEMS) accelerometer - Google Patents

Abstract

The invention discloses a three-dimensional wireless input device based on an MEMS accelerometer. The three-dimensional wireless input device comprises a two-dimensional input system and a three-dimensional accelerometer motion model, wherein the two-dimensional input system comprises a far-end subsystem and a host terminal subsystem; and the three-dimensional accelerometer motion model comprises a cubic carrier, a double-shaft accelerometer and a single-shaft accelerometer. According to the three-dimensional wireless input device, two-dimensional translation of a two-dimensional device can be controlled through the work mode of rotation of the accelerometer, namely, a cursor on a screen can be controlled to move vertically and horizontally through front-back and horizontal rotation of the double-shaft accelerometer; the work mode is different from a translation mode of an ordinary mouse, the sensitivity of the input device is improved, and the application range is expanded simultaneously, so that the input device is not confined to smooth and flat operating surfaces and capable of being operated freely in space, and high practical values and wide application prospects are provided.

Description

A kind of 3-D wireless input media based on mems accelerometer

Technical field

The present invention relates to a kind of 3-D wireless input media, specifically, relate to a kind of 3-D wireless input media based on mems accelerometer.

Background technology

The people is normally carrying out in the process of man-machine interaction, and the understanding in system for computer state and the operational process all realizes by man-machine interface.Computer input equipment on the market has at present: keyboard, mouse, Trackpad, TrackPoint, trace ball and touch-screen etc.The keyboard input is that the user carries out the main input pattern that character knocks input, and modal keyboard is the QWERT keyboard on the market, generally adopts the square button of l/2in, and the space between the button is 1/4in.The key face is recessed a little, adopts milled sand surface, and the light reflection and the finger that have reduced button skid, and allow finger tip and button that excellent contact is arranged; No matter be at notebook computer or in desktop computer market, mouse is the most popular in to click and mobilely to be the input equipment of main input pattern except keyboard now.The input pattern of clicking and moving with mouse is different, and Trackpad (Touch Pad or Track Pad) is to touch the mobile input equipment of main input pattern that is with hand; Touch-screen is a kind of direct input pattern at the enterprising line operate of screen; TrackPoint is that another kind is popular in the input equipment of notebook computer, is that the finger that IBM Corporation aims at the ThinkPad research and development is taken the family input pattern; The principle of work of trace ball is similar with mouse, is an inverted mouse.The amount of exercise of its spheroid rotation is converted into the displacement of XY direction, and the cursor of controlling on the screen moves.

In sum, existing radio input device all is input and the response that comes opertaing device by the mode of button, exist the reaction time slow, sensitivity is not high and be confined to smooth smooth defect problems such as operating surface.

Summary of the invention

The problems referred to above at the prior art existence, the purpose of this invention is to provide a kind of 3-D wireless input media based on mems accelerometer, replace mechanical controling part with MEMS, realization adopts the mode of operation of rotary accelerometer to handle the two-dimensional translation of two-dimensional device, with sensitivity and its usable range of expansion that increases input media, can enough arbitrarily operate in any space.

For achieving the above object, the technical solution used in the present invention is as follows:

A kind of 3-D wireless input media based on mems accelerometer comprises a two-dimentional input system and a three-dimensional accelerometer motion model; Described two-dimentional input system comprises far-end subsystem and host side subsystem, described far-end subsystem comprises MEMS acceleration transducer, microcontroller and less radio-frequency transport module, with collection, processing and the wireless transmission of finishing acceleration signal, described host side subsystem comprises radio receiving transmitting module, master controller and USB interface, handle with the reception of realization less radio-frequency and the communications protocol coding of input signal, and be connected with main frame by USB interface; Described three-dimensional accelerometer motion model comprises a cube carrier and a twin-axis accelerometer and a single-axis accelerometer, described twin-axis accelerometer and single-axis accelerometer are separately positioned on two mutually orthogonal planes of cube carrier, and described twin-axis accelerometer and single-axis accelerometer all are connected with MEMS acceleration transducer in the far-end subsystem.

As a kind of preferred version, described twin-axis accelerometer is arranged on the end face of cube carrier, and two sensitive axes is pointed to X-axis and the Y-axis of horizontal direction respectively; Described single-axis accelerometer is arranged on the side of cube carrier, and its sensitive axes is pointed to the direction of acceleration of gravity.

As further preferred version, described twin-axis accelerometer is ADXL203 type twin-axis accelerometer, and described individual axis acceleration is counted ADXL103 type single-axis accelerometer.

As a kind of preferred version, described less radio-frequency transport module adopts frequency hopping mode spread-spectrum.

As a kind of preferred version, described radio receiving transmitting module adopts the GFSK modulating mode that transfer rate is provided.

As a kind of preferred version, described radio receiving transmitting module is the nRF2401 chip.

As a kind of preferred version, described microcontroller comprises radial basis function (Radial basis function, RBF) neural network, EMD decomposing module, WAVELET PACKET DECOMPOSITION module and S-G (Savitzky-Golay) smoothing filter.

As further preferred version, the processing procedure that described microcontroller carries out acceleration signal comprises the steps:

A) obtain the acceleration signal that the MEMS acceleration transducer collects and be transferred to the RBF neural network by the I/O interface;

B) acceleration signal after the analysis of RBF neural network prediction is transferred to the EMD decomposing module;

C) acceleration signal after the EMD decomposing module is decomposed is transferred to the WAVELET PACKET DECOMPOSITION module;

D) acceleration signal after the WAVELET PACKET DECOMPOSITION module is decomposed again is transferred to the S-G smoothing filter;

E) acceleration signal after the S-G smoothing filter carries out filtering and noise reduction is transferred to the less radio-frequency transport module.

Compared with prior art, 3-D wireless input media based on mems accelerometer provided by the invention, utilize the MEMS acceleration transducer to come responsive exercise data, and integrated less radio-frequency, technology such as embedded and ARM technology and USB communication, by designing a three-dimensional accelerometer motion model that comprises the two-dimentional input system of far-end subsystem and host side subsystem and utilize the position coupled relation between each output shaft of accelerometer to set up, realized the tracking that rotatablely moves in real time under the three-dimensional environment, thereby the mode of operation that has realized the employing rotary accelerometer is handled the two-dimensional translation of two-dimensional device, that is: front and back by a twin-axis accelerometer, left-right rotation, control cursor on the screen about, move left and right; This mode of operation both had been different from the translation mode of general mouse, increased the sensitivity of input media again, also expanded its usable range simultaneously, made it no longer be confined to smooth smooth operating surface, and can arbitrarily operate in the space, have extremely strong practical value and wide application prospect.

Description of drawings

Fig. 1 is the structural representation of the two-dimentional input system described in the embodiment;

Fig. 2 is the structural representation of the three-dimensional accelerometer motion model described in the embodiment.

Among the figure: 1, cube carrier; 2, twin-axis accelerometer; 3, single-axis accelerometer.

Embodiment

Below in conjunction with the drawings and specific embodiments technical scheme of the present invention is done further and to be elaborated:

A kind of 3-D wireless input media based on mems accelerometer provided by the invention, comprise a two-dimentional input system (as shown in Figure 1) and a three-dimensional accelerometer motion model (as shown in Figure 2), described two-dimentional input system comprises far-end subsystem and host side subsystem, described far-end subsystem comprises the MEMS acceleration transducer, microcontroller and less radio-frequency transport module, to finish the collection of acceleration signal, handle and wireless transmission, described host side subsystem comprises radio receiving transmitting module, master controller and USB interface, handle with the reception of realization less radio-frequency and the communications protocol coding of input signal, and be connected with main frame by USB interface; Described three-dimensional accelerometer motion model comprises a cube carrier 1 and a twin-axis accelerometer 2 and a single-axis accelerometer 3, described twin-axis accelerometer 2 and single-axis accelerometer 3 are separately positioned on two mutually orthogonal planes of cube carrier 1, and described twin-axis accelerometer 2 and single-axis accelerometer 3 all are connected with MEMS acceleration transducer in the far-end subsystem.

As a kind of preferred version, described twin-axis accelerometer is arranged on the end face of cube carrier, and two sensitive axes Ac1 and Ac2 point to X-axis and the Y-axis of horizontal direction respectively; Described single-axis accelerometer is arranged on the side of cube carrier, and its sensitive axes Ac3 points to the direction of acceleration of gravity; Can obtain the equation of motion group of three-dimensional MEMS accelerometer model thus:

$\left\{\begin{array}{c}{\mathrm{Ac}}_1=g*(-\cos \left(x\right)*\sin \left(y\right)*\sin \left(z\right)+\cos \left(z\right)*\sin \left(x\right))\\ {\mathrm{Ac}}_2=g*(-\cos \left(x\right)*\cos \left(z\right)*\sin \left(y\right)-\sin \left(x\right)*\sin \left(z\right))\\ {\mathrm{Ac}}_3=g*\cos \left(x\right)*\cos \left(y\right)\end{array}\right.$

Above-mentioned system of equations is a ternary cubic equation group that has trigonometric function, has shown three output of mems accelerometer and the nonlinear relationship between the three-dimensional rotation parameter.By this solution of equations is analysed the angle parameter that just can obtain three-dimensional rotating, thereby obtain real rotary movement.

Described twin-axis accelerometer can be selected ADXL203 type twin-axis accelerometer for use, and described single-axis accelerometer can be selected ADXL103 type single-axis accelerometer for use.

As a kind of preferred version, described less radio-frequency transport module adopts frequency hopping mode spread-spectrum, to improve the ability of the anti-electromagnetic interference (EMI) of mems accelerometer input system greatly, makes that the wireless data transmission is more reliable; Described radio receiving transmitting module adopts the GFSK modulating mode that transfer rate is provided, the nRF2401 chip that can select for use Nordic company to produce.

Because mems accelerometer and data acquisition circuit are subjected to the influence of factors such as environmental interference, make the acceleration signal that obtains contain a large amount of noises, thereby influence is based on the operating performance of mems accelerometer input system, therefore described microcontroller preferably includes radial basis function (Radial basis function, RBF) neural network, EMD decomposing module, WAVELET PACKET DECOMPOSITION module and S-G (Savitzky-Golay) smoothing filter; The processing procedure that adopts described microcontroller to carry out acceleration signal comprises the steps:

A) obtain the acceleration signal that the MEMS acceleration transducer collects and be transferred to the RBF neural network by the I/O interface;

B) acceleration signal after the analysis of RBF neural network prediction is transferred to the EMD decomposing module;

C) acceleration signal after the EMD decomposing module is decomposed is transferred to the WAVELET PACKET DECOMPOSITION module;

D) acceleration signal after the WAVELET PACKET DECOMPOSITION module is decomposed again is transferred to the S-G smoothing filter;

E) acceleration signal after the S-G smoothing filter carries out filtering and noise reduction is transferred to the less radio-frequency transport module.

Experimental result shows, can subdue noise in the original accelerometer signal well by above-mentioned processing, can improve the signal to noise ratio (S/N ratio) of accelerometer signal greatly.

In sum, 3-D wireless input media based on mems accelerometer provided by the invention, utilize the MEMS acceleration transducer to come responsive exercise data, and integrated less radio-frequency, technology such as embedded and ARM technology and USB communication, by designing a three-dimensional accelerometer motion model that comprises the two-dimentional input system of far-end subsystem and host side subsystem and utilize the position coupled relation between each output shaft of accelerometer to set up, realized the tracking that rotatablely moves in real time under the three-dimensional environment, thereby the mode of operation that has realized the employing rotary accelerometer is handled the two-dimensional translation of two-dimensional device, that is: front and back by a twin-axis accelerometer, left-right rotation, control cursor on the screen about, move left and right; This mode of operation both had been different from the translation mode of general mouse, increased the sensitivity of input media again, also expanded its usable range simultaneously, made it no longer be confined to smooth smooth operating surface, and can arbitrarily operate in the space, have extremely strong practical value and wide application prospect.

Be necessary at last to be pointed out that at this; above-mentioned explanation only is used for technical scheme of the present invention is described in further detail; can not be interpreted as limiting the scope of the invention, some nonessential improvement that those skilled in the art's foregoing according to the present invention is made and adjustment all belong to protection scope of the present invention.

Claims (8)

1. the 3-D wireless input media based on mems accelerometer is characterized in that: comprise a two-dimentional input system and a three-dimensional accelerometer motion model; Described two-dimentional input system comprises far-end subsystem and host side subsystem, described far-end subsystem comprises MEMS acceleration transducer, microcontroller and less radio-frequency transport module, with collection, processing and the wireless transmission of finishing acceleration signal, described host side subsystem comprises radio receiving transmitting module, master controller and USB interface, handle with the reception of realization less radio-frequency and the communications protocol coding of input signal, and be connected with main frame by USB interface; Described three-dimensional accelerometer motion model comprises a cube carrier and a twin-axis accelerometer and a single-axis accelerometer, described twin-axis accelerometer and single-axis accelerometer are separately positioned on two mutually orthogonal planes of cube carrier, and described twin-axis accelerometer and single-axis accelerometer all are connected with MEMS acceleration transducer in the far-end subsystem.

2. 3-D wireless input media as claimed in claim 1, it is characterized in that: described twin-axis accelerometer is arranged on the end face of cube carrier, and two sensitive axes is pointed to X-axis and the Y-axis of horizontal direction respectively; Described single-axis accelerometer is arranged on the side of cube carrier, and its sensitive axes is pointed to the direction of acceleration of gravity.

3. 3-D wireless input media as claimed in claim 2, it is characterized in that: described twin-axis accelerometer is ADXL203 type twin-axis accelerometer, and described individual axis acceleration is counted ADXL103 type single-axis accelerometer.

4. 3-D wireless input media as claimed in claim 1 is characterized in that: described less radio-frequency transport module employing frequency hopping mode spread-spectrum.

5. 3-D wireless input media as claimed in claim 1 is characterized in that: described radio receiving transmitting module adopts the GFSK modulating mode that transfer rate is provided.

6. 3-D wireless input media as claimed in claim 5, it is characterized in that: described radio receiving transmitting module is the nRF2401 chip.

7. 3-D wireless input media as claimed in claim 1, it is characterized in that: described microcontroller comprises radial basis function (RBF) neural network, EMD decomposing module, WAVELET PACKET DECOMPOSITION module and S-G smoothing filter.

8. 3-D wireless input media as claimed in claim 7 is characterized in that, the processing procedure that described microcontroller carries out acceleration signal comprises the steps:

A) obtain the acceleration signal that the MEMS acceleration transducer collects and be transferred to the RBF neural network by the I/O interface;

B) acceleration signal after the analysis of RBF neural network prediction is transferred to the EMD decomposing module;

C) acceleration signal after the EMD decomposing module is decomposed is transferred to the WAVELET PACKET DECOMPOSITION module;

D) acceleration signal after the WAVELET PACKET DECOMPOSITION module is decomposed again is transferred to the S-G smoothing filter;

E) acceleration signal after the S-G smoothing filter carries out filtering and noise reduction is transferred to the less radio-frequency transport module.

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