CN108563341A - A kind of three-dimensional touch electronic pen and method with vibrotactile feedback - Google Patents

Abstract

The present invention relates to a kind of three-dimensional touch electronic pens and method with vibrotactile feedback, belong to three-dimensional touch electronic pen and method.Including power module, nine axle acceleration gyro sensors, key-press module, microprocessor, localization by ultrasonic module, wireless communication module and vibration module；Wherein vibration module：Including linear electric machine one and linear electric machine two, electronic pen both ends are individually fixed in, respectively there are two direction of vibration for each motor, are driven to vibration module using microprocessor, and then realize various dimensions vibrational feedback.Advantage is：The identification of current interactive operation is completed using localization by ultrasonic and button operation, it realizes vibrational feedback effect that is realistic and immersing sense, can be commonly to be touched in three-dimensional space pen-based interaction, rotate, the operations such as dragging provide corresponding vibrational feedback, improve immersion sense and the sense of reality of interactive operation.

Description

A three-dimensional touch electronic pen with vibration and tactile feedback and its method

technical field

The invention relates to a three-dimensional touch electronic pen and a method thereof, which are applied in the fields of human-computer interaction, education informatization, virtual reality interactive control and the like.

Background technique

In recent years, how to provide users with a more realistic and immersive interactive experience has become a major issue in the field of human-computer interaction research. Pen-based interaction, as a mainstream form of human-computer interaction in the future, has become a research hotspot.

Pen-based interaction is a human-computer interaction method with great research value. Since most people have long-term experience of using paper and pen, pen-based operation will also conform to their operating habits, reduce learning costs, and improve operating comfort. As an input and control device, the electronic pen is portable and flexible. There are already some application examples in real products. For example, Microsoft SurfacePro series computers are compatible with specially designed electronic pens, which can realize common pen-style interactions such as writing and erasing. Operational simulation. In addition, many mobile devices, such as Samsung Galaxy Note series mobile phones, are also equipped with S-pen electronic pens, which are convenient for users to perform interactive operations such as writing.

With the progress of research, the pen-style interactive space has gradually changed from two-dimensional plane to three-dimensional space. The content of interactive operation is also based on basic operations such as simple writing and erasing, and new operations unique to three-dimensional space are added, such as Rotation, etc., have important application potential in fields such as virtual reality and education informatization. However, current research mainly focuses on positioning and sensing technology in three-dimensional space, and there are few related studies on user interaction experience. At the same time, although the current interactive technology meets the basic interactive functional requirements, such as clicking, three-digit writing, etc., the interactive experience and interactive accuracy need to be improved. In a wider range of practical applications (such as teaching demonstrations, entertainment functions, etc.), many scenarios require users to perform interactive operations with higher complexity and precision, such as touching a specific area in the space, with a certain speed, axis Rotate in direction and direction, drag at a certain speed and direction, etc. For the above-mentioned interactive operations, there is currently no effective feedback method, which indicates that the user's interactive experience is poor, and the accuracy of the interactive completion is low. Therefore, for all kinds of pen-style interactive operations realized in three-dimensional space, realistic vibration feedback can be generated according to a certain control method, thereby improving the user's interactive experience and operational accuracy.

Chinese patent application "a three-dimensional large-space multi-channel pen interactive system", application number 201611157044.0, discloses a multi-channel three-dimensional pen interactive system and method based on ultrasonic positioning, including: microprocessor, PVDF piezoelectric film, MEMS six-axis acceleration/gyroscope, microphone, Bluetooth communication chip, pressure sensor, button and other miniature and small multi-channel sensing sensors and components. Support the extraction of three-dimensional positioning and attitude information of the electronic pen, and send the relevant data to the host through the Bluetooth chip after processing. However, the system does not integrate vibration components and related drive circuits, and does not support the tactile feedback function.

Contents of the invention

The present invention provides a three-dimensional touch electronic pen with vibration tactile feedback and its method to solve the problems that the traditional pen-type interactive system does not support vibration feedback effect with high sense of reality and realizes low precision for some interactive operations.

The technical solution adopted by the present invention is: a three-dimensional touch electronic pen with vibration and tactile feedback, including a power supply module, a nine-axis acceleration gyroscope sensor, a key module, a microprocessor, an ultrasonic positioning module, a wireless communication module and a vibration module; Among them, the vibration module: includes linear motor 1 and linear motor 2, which are respectively fixed at both ends of the electronic pen. Each motor has two vibration directions, and the vibration module is driven by a microprocessor to realize multi-dimensional vibration feedback;

The nine-axis acceleration gyro sensor of the present invention: used for extracting acceleration and angular velocity signals, including obtaining the linear velocity, angular velocity, linear acceleration, angular acceleration and attitude information of the electronic pen at any moment, and transmitting the extracted acceleration and angular velocity signals to the microprocessor;

The button module of the present invention: the button module is used to provide shortcut functions;

The power module of the present invention: includes a battery 101 and a boost circuit 102 to supply power for the entire system;

The wireless communication module of the present invention: adopts bluetooth, ZigBee etc. It is used to send the attitude and speed information of the electronic pen to the host computer and receive the control and configuration information sent by the host computer;

Microprocessor of the present invention: adopt single-chip microcomputer, DSP etc. It is used to realize two kinds of vibration drives of static waveform through storage and dynamic waveform generation, and is also responsible for acceleration gyroscope sensor signal acquisition and processing, Bluetooth communication chip control, key processing, and data transmission and reception between the host computer;

The ultrasonic positioning module of the present invention includes an ultrasonic transmitting module for periodically emitting ultrasonic signals.

A vibration feedback control method of a three-dimensional touch electronic pen with vibration tactile feedback, including touch, rotation and drag in three-dimensional pen interaction, wherein:

(1) The specific process of touching is as follows:

1), the user normally holds the electronic pen, enters the touch mode through key operation, the positioning signal module starts to emit infrared and ultrasonic signals periodically, and the host computer uses the principle of ultrasonic positioning to obtain the real-time three-dimensional coordinates P _n (x _n ,y _n) of the electronic pen ,z _n ), where n is the current positioning period;

2) In each positioning cycle, the upper computer uses the space coordinates of the electronic pen to detect the collision with the virtual object in the three-dimensional space. Let a virtual cubic area M in the space be {m|x _m1 <x<x _m2 , y _m1 <y<y _m2 , z _m1 <z<z _m2 }, if the coordinate P _i (xi _, y _i , z _i ) of the electronic pen is within M in a certain positioning period, it is considered that the electronic pen touches a certain position in the current period. Object, at this time, the host computer sends relevant instructions to the electronic pen, including the command to start vibration and the pre-stored waveform information called. If no collision is detected, the command to stop vibration is sent to the electronic pen.

3) After the electronic pen receives the instruction from the host computer, if it is a vibration start instruction, it will call the waveform corresponding to the current object number from the prefabricated waveform library for output. The driving signal uses a sinusoidal signal, a triangle signal or a PWM signal, and the driving voltage peak The peak value is V _pp , and the frequency is f _x ; if it is a stop vibration command, stop the vibration;

4) If the user exits the touch mode through key operation, the positioning module stops sending positioning signals, and the electronic pen directly stops vibrating;

(2) The specific process of rotation is as follows:

1) The user normally holds the electronic pen, enters the rotation mode through key operation, and the host computer sends instructions to the electronic pen to start dynamic generation and output of vibration feedback waveforms;

2) After the electronic pen receives the rotation feedback command, it first processes and judges the data returned by the nine-axis acceleration gyroscope sensor, and generates a dynamic driving waveform on this basis;

3) The three-dimensional actual rotation axis of the electronic pen can be any axis in the three-dimensional space, and can be regarded as the vector sum of the three axial rotations of X, Y, and Z. Therefore, combined with the vibration direction realized by the linear motor, by comparing the X , Y, Z three axis angular velocity to determine the current main axis of rotation, and based on this to select the vibration direction of the linear motor, suppose the angular velocity of the electronic pen around the X, Y, Z axis at this moment is ωx, ωy, ωz, If ωz<ωy, the main rotation axis of the electronic pen is considered to be the Y axis, the vibration direction of the linear motor unit is taken as the Z axis direction, and the driving signal frequency is f0; if ωz≥ωy, the main rotation axis of the electronic pen is considered to be the Z axis , taking the vibration direction of the linear motor unit as the Y-axis direction, and the drive signal as the frequency f1;

4) Calculate the modulus of the current angular velocity And according to the following mapping relationship, the peak-to-peak value of the driving signal voltage V _pp is obtained, and the real-time angular velocity is linearly mapped to the peak-to-peak value of the driving voltage, Vpp1=k*ω, Vpp1 is: the voltage calculated according to the linear mapping, k is a proportional coefficient, Setting the driving voltage threshold as V _max , when Vpp1<V _max , Vpp=Vpp1; when Vpp1>V _max , Vpp=V _max ;

5) According to the information of the nine-axis acceleration gyroscope sensor, determine the downward direction of the current main rotation axis, clockwise or counterclockwise, determine the respective force simulation directions of linear motor 1 and linear motor 2 in the electronic pen, and then determine the direction of the drive signal polarity;

6) Output dynamic driving waveform, which is characterized by the vibration direction perpendicular to the main axis of rotation, the vibration intensity is positively correlated with the modulus of the combined angular velocity of the rotation, and the direction of the simulation effect of linear motor 1 and linear motor 2 at both ends is upward to the main rotation axis The direction of rotation is the same to simulate the torque effect during the rotation process;

7) If the rotation mode is exited by key operation, the electronic pen will stop vibrating directly;

(3) The specific process of dragging is as follows:

1) The user normally holds the electronic pen and enters the drag mode through button operation, and the host computer sends instructions to the electronic pen to start dynamic generation and output of vibration feedback waveforms;

2) After the electronic pen receives the drag feedback command, it first processes and judges according to the data returned by the nine-axis acceleration gyroscope sensor, and generates a dynamic driving waveform on this basis; the driving waveform of the vibration in the drag mode uses a PWM waveform, Adjust frequency, pulse width;

3) The three-dimensional actual translation direction of the electronic pen can be any direction in the three-dimensional space, and can be regarded as the vector sum of translation in the three directions of X, Y, and Z. Therefore, combined with the vibration direction that can be realized by the linear motor, by comparing the X , Y, Z linear velocity in the three axes to determine the current main translation direction, and based on this to select the linear motor vibration direction, using the acceleration data returned by the nine-axis acceleration gyroscope sensor to integrate the electronic pen at the X , the linear velocities in the Y and Z directions are vx, vy, vz respectively, if vz<vy, it is considered that the main dragging direction of the electronic pen is the Y direction, the vibration direction of the linear motor unit is the Y axis direction, and the driving signal frequency is f1; if vz ≥vy means that the main dragging direction of the electronic pen is the Z direction, the vibration direction of the linear motor unit is the Y-axis direction, and the driving signal frequency is f1;

4) Calculate the modulus of the current line speed And obtain the PWM duty ratio according to the following mapping relationship, the driving signal duty ratio is DR, set the driving signal duty ratio threshold as DRmax, and linearly map the modulus of the real-time closing speed to the PWM duty ratio, DR1=k *v, DR1 is the duty cycle obtained according to the mapping relationship, k is the proportional coefficient, when DR1<DRmax, DR=DRp1; when DR1≥DRmax, DR=DRmax;

5) Output the dynamic driving waveform, which is characterized by the same direction of vibration as the main dragging direction, and the vibration intensity is positively correlated with the modulus of the dragging line speed, so as to simulate the friction effect during the dragging process;

6) If the user exits the dragging mode through a button operation, the electronic pen stops vibrating directly.

in:

Touch definition: the user normally holds the electronic pen, enters the touch mode through button operation, and then touches a specific area in the three-dimensional space with the electronic pen according to the prompts of the host computer, and the host computer displays the corresponding touch operation. interactive content;

Rotation definition: the user holds the electronic pen normally, enters the rotation mode through button operation, and then rotates the electronic pen in a three-dimensional space according to a certain direction, axis and speed according to the prompts of the host computer, and the host computer displays the interaction corresponding to the rotation operation content;

Definition of drag and drop: the user normally holds the electronic pen, enters the rotation mode through button operation, and then drags the electronic pen in the three-dimensional space according to a certain direction and speed according to the prompt of the host computer, and the host computer displays the interaction corresponding to the drag operation content.

The present invention provides a tactile feedback control method of a three-dimensional touch electronic pen, including: realizing the identification of the operation mode and the triggering of a specific operation through the combination of button operation and ultrasonic positioning; realizing the vibration feedback of the touch operation through the static waveform call; The dynamic waveform is generated by using the angular velocity information returned by the sensor to realize the vibration feedback of the rotation operation; the dynamic waveform is generated by using the linear velocity information returned by the sensor to realize the vibration feedback of the drag operation.

The invention has the advantages of: using ultrasonic positioning and button operation to complete the identification of the current interactive operation, and according to the type of interactive operation, adopting the method of static waveform calling or dynamic waveform generation, combined with the current motion information of the electronic pen, to achieve a sense of reality and immersion Sensitive vibration feedback effect can provide corresponding vibration feedback for touch, rotate, drag and other operations commonly used in three-dimensional pen-style interaction, improving the immersion and realism of interactive operations.

Description of drawings

Fig. 1 is a block diagram of electronic pen circuit of the present invention;

Fig. 2 is a schematic diagram of the hardware composition of the electronic pen of the present invention;

Fig. 3 is a principle diagram of ultrasonic positioning of the present invention;

Fig. 4 is a schematic diagram of the resonant frequency point characteristics of the linear motor of the present invention;

Fig. 5 is a kind of asymmetric waveform driving schematic diagram of the linear motor of the present invention;

Fig. 6 is the PWM waveform driving schematic diagram of the linear motor of the present invention;

Fig. 7 is a flow chart of touch feedback in the present invention;

Fig. 8 is a flow chart of rotation feedback of the present invention;

Fig. 9 is a schematic diagram of the rotation feedback of the present invention;

Fig. 10 is a flow chart of drag feedback in the present invention;

Fig. 11 is a schematic diagram of drag feedback in the present invention.

Detailed ways

A three-dimensional touch electronic pen with vibration and tactile feedback:

Including power module 1, nine-axis acceleration gyro sensor 2, button module 3, microprocessor 4, ultrasonic positioning module 5, wireless communication module 6 and vibration module 7; where:

Vibration module 7: including linear motor 1 701 and linear motor 2 702, which are respectively fixed at both ends of the electronic pen, each motor has two vibration directions, and the vibration module is driven by a microprocessor to realize multi-dimensional vibration feedback;

The vibration module uses the combination of components driven by current to produce vibration effects, such as linear motors, piezoelectric ceramics, eccentric rotating masses, etc., which are characterized by one or more resonant frequencies, and have strong vibration responses only near the resonant frequencies, and in The vibration directions near different resonance frequencies are different;

Nine-axis acceleration gyro sensor 2: used to extract acceleration and angular velocity signals, including obtaining the linear velocity, angular velocity, linear acceleration, angular acceleration and attitude information of the electronic pen at any time, and transmitting the extracted acceleration and angular velocity signals to the microprocessor device;

Button module 3: The button module is used to provide shortcut functions, including touch, rotate, and drag;

Power supply module 1: including a battery 101 and a boost circuit 102, supplying power for the entire system;

Wireless communication module 6: Bluetooth, ZigBee, etc. can be used to send the attitude and speed information of the electronic pen to the host computer and receive control and configuration information sent by the host computer;

Microprocessor 4: Single-chip microcomputer, DSP, etc. can be used to realize two kinds of vibration drives through storage of static waveforms and dynamic waveform generation. It is also responsible for acceleration gyroscope sensor signal acquisition and processing, Bluetooth communication chip control, key processing, Data transmission and reception with the host computer;

The microprocessor supports the following two drivers:

Static waveform storage and recall function: It can store a certain amount of prefabricated waveform effects, such as driving waveforms used to generate tactile feedback when touching different virtual objects.

Dynamic waveform generation and cache function: used for dynamic waveform generation, according to the current working mode and real-time linear velocity, angular velocity, attitude and other information obtained by the microprocessor, real-time driving waveforms can be generated and written into the cache.

(7) Ultrasonic positioning module: including an infrared emitting module and an ultrasonic emitting module, which are used to periodically emit infrared and ultrasonic signals, which are received and calculated by the ultrasonic three-dimensional positioning system of the upper computer. Using the principle of ultrasonic positioning, the real-time spatial position of the electronic pen can be obtained The three-dimensional coordinates of the computer, and the location information is sent back to the electronic pen through Bluetooth communication, etc., for further processing or judgment.

A vibration feedback control method of a three-dimensional touch electronic pen with vibration tactile feedback, including touch, rotation and drag in three-dimensional pen interaction, and driving the vibration element group by calling a prefabricated waveform or generating a dynamic waveform, Firstly, the common operations in 3D space pen-style interaction are defined as follows: Among them:

Touch: The user normally holds the electronic pen, enters the touch mode through button operation, and then touches a specific area in the three-dimensional space with the electronic pen according to the prompts of the host computer, and the host computer displays the interaction corresponding to the touch operation content;

Rotation: The user normally holds the electronic pen, enters the rotation mode through button operation, and then rotates the electronic pen in the three-dimensional space according to a certain direction, axis and speed according to the prompts of the host computer, and at the same time, the host computer displays the interactive content corresponding to the rotation operation ;

Drag and drop: The user holds the electronic pen normally, enters the rotation mode through button operation, and then drags the electronic pen in the three-dimensional space according to a certain direction and speed according to the prompt of the host computer, and at the same time, the host computer displays the interactive content corresponding to the drag operation ;

(1) The specific process of touching is as follows:

1), the user normally holds the electronic pen, enters the touch mode through key operation, the positioning signal module starts to emit infrared and ultrasonic signals periodically, and the host computer uses the principle of ultrasonic positioning to obtain the real-time three-dimensional coordinates P _n (x _n ,y _n) of the electronic pen ,z _n ), where n is the current positioning cycle;

2) In each positioning cycle, the upper computer uses the space coordinates of the electronic pen to detect the collision with the virtual object in the three-dimensional space. Let a virtual cubic area M in the space be {m|x _m1 <x<x _m2 , y _m1 <y<y _m2 , z _m1 <z<z _m2 }, if the coordinate P _i (xi _, y _i , z _i ) of the electronic pen is within M in a certain positioning period, it is considered that the electronic pen touches a certain position in the current period. Object, at this time, the host computer sends relevant instructions to the electronic pen, including the command to start vibration and the pre-stored waveform information called. If no collision is detected, the command to stop vibration is sent to the electronic pen.

3) After the electronic pen receives the instruction from the host computer, if it is a vibration start instruction, it will call the waveform corresponding to the current object number from the prefabricated waveform library for output. The driving signal uses a sinusoidal signal, a triangle signal or a PWM signal, and the driving voltage peak The peak value is V _pp , and the frequency is f _x ; if it is a stop vibration command, stop the vibration;

4) If the user exits the touch mode through key operation, the positioning module stops sending positioning signals, and the electronic pen directly stops vibrating;

(2) The specific process of rotation is as follows:

1) The user normally holds the electronic pen, enters the rotation mode through key operation, and the host computer sends instructions to the electronic pen to start dynamic generation and output of vibration feedback waveforms;

2) After the electronic pen receives the rotation feedback command, it first processes and judges according to the data returned by the nine-axis acceleration gyroscope sensor, and then generates a dynamic driving waveform on this basis; the vibration and tactile feedback driving waveform of the rotation operation is realized by using an asymmetrical waveform One-sided force simulation effect, combined with the front and rear motor groups of the electronic pen, makes it produce the force simulation effect in the opposite direction,

3) The three-dimensional actual rotation axis of the electronic pen can be any axis in the three-dimensional space, and can be regarded as the vector sum of the three axial rotations of X, Y, and Z. Therefore, combined with the vibration direction realized by the linear motor, by comparing the X , Y, Z three axis angular velocity to determine the current main axis of rotation, and based on this to select the vibration direction of the linear motor, suppose the angular velocity of the electronic pen around the X, Y, Z axis at this moment is ωx, ωy, ωz, If ωz<ωy, it is considered that the main rotation axis of the electronic pen is the Y axis, the vibration direction of the linear motor unit is taken as the Z axis direction, and the frequency of the driving signal is f ₀ ; if ωz≥ωy, the main rotation axis of the electronic pen is considered to be Z axis, take the vibration direction of the linear motor unit as the Y-axis direction, and the drive signal as the frequency;

4) Calculate the modulus of the current angular velocity And according to the following mapping relationship, the peak-to-peak value of the driving signal voltage V _pp is obtained, and the real-time angular velocity is linearly mapped to the peak-to-peak value of the driving voltage, Vpp1=k*ω, Vpp1 is: the voltage calculated according to the linear mapping, k is a proportional coefficient, Setting the driving voltage threshold as V _max , when Vpp1<V _max , Vpp=Vpp1; when Vpp1>V _max , Vpp=V _max ;

5) According to the information of the nine-axis acceleration gyro sensor, determine the downward direction of the current main rotation axis, clockwise or counterclockwise, determine the respective force simulation directions of the linear motor 1 701 and the linear motor 2 702 in the electronic pen, and then determine the drive the polarity of the signal;

6) Output dynamic driving waveform, which is characterized by the vibration direction perpendicular to the main axis of rotation, the vibration intensity is positively correlated with the modulus of the rotational angular velocity, the direction of the force simulation effect of linear motor 1 and linear motor 2 702 at both ends is related to the main rotation axis The upward rotation direction is the same to simulate the torque effect during rotation;

7) If the rotation mode is exited by key operation, the electronic pen will stop vibrating directly;

(3) The specific process of dragging is as follows:

1) The user normally holds the electronic pen and enters the drag mode through button operation, and the host computer sends instructions to the electronic pen to start dynamic generation and output of vibration feedback waveforms;

2) After the electronic pen receives the drag feedback command, it first processes and judges according to the data returned by the nine-axis acceleration gyroscope sensor, and generates a dynamic driving waveform on this basis; the driving waveform of the vibration in the drag mode uses a PWM waveform, Adjust frequency, pulse width;

3) The three-dimensional actual translation direction of the electronic pen can be any direction in the three-dimensional space, and can be regarded as the vector sum of translation in the three directions of X, Y, and Z. Therefore, combined with the vibration direction that can be realized by the linear motor, by comparing the X , Y, Z linear velocity in the three axes to determine the current main translation direction, and based on this to select the linear motor vibration direction, using the acceleration data returned by the nine-axis acceleration gyroscope sensor to integrate the electronic pen at the X , the linear velocities in the Y and Z directions are vx, vy, vz respectively, if vz<vy, it is considered that the main dragging direction of the electronic pen is the Y direction, the vibration direction of the linear motor unit is the Y axis direction, and the driving signal frequency is f1; if vz ≥vy means that the main dragging direction of the electronic pen is the Z direction, the vibration direction of the linear motor unit is the Y-axis direction, and the driving signal frequency is f1;

4) Calculate the modulus of the current line speed According to the following mapping relationship, the PWM duty ratio and the driving signal duty ratio DR are obtained, and the threshold value of the driving signal duty ratio is set to DRmax, and the modulus of the real-time closing speed is linearly mapped to the PWM duty ratio, DR1=k* v, DR1 is the duty cycle obtained according to the mapping relationship, k is the proportional coefficient, when DR1<DRmax, DR=DRp1; when DR1≥DRmax, DR=DRmax;

5) Output the dynamic driving waveform, which is characterized by the same direction of vibration as the main dragging direction, and the vibration intensity is positively correlated with the modulus of the dragging line speed, so as to simulate the friction effect during the dragging process;

6) If the user exits the dragging mode through a button operation, the electronic pen stops vibrating directly.

The present invention will be specifically described below in conjunction with accompanying drawings 1-11.

The electronic pen in Figure 1 includes a nine-axis acceleration gyro sensor, a button module, a power module, a microprocessor, a wireless communication module, an ultrasonic positioning module and a vibration module.

FIG. 2 is a schematic diagram of the hardware structure of the electronic pen. The vibration module consists of two linear motors respectively fixed at the two ends of the electronic pen.

Fig. 3 is a principle diagram of ultrasonic positioning. After pressing any one of the three buttons, the ultrasonic transmitting module periodically transmits infrared and ultrasonic signals. Ultrasonic signals are respectively received by three receivers. Use the infrared signal as the basis for the measurement of ultrasonic propagation time to extract the propagation time of ultrasonic waves. After setting the propagation speed of ultrasonic waves, multiply the propagation time by the propagation speed to obtain the propagation distances l ₁ , l ₂ , and l _{3 from the electronic pen to each receiver.} Finally, geometric positioning is used to calculate the three-dimensional coordinates P _n (x _n , y _n , z _n ) of ultrasonic positioning, where n is the current positioning cycle.

In Fig. 4, a linear motor 1 701 and a linear motor 2 702 are respectively fixed at both ends of the electronic pen. The linear motor used is in the shape of a cuboid with two resonant frequency points f ₀ and f ₁ , and has a strong Vibration intensity, when the frequency of the driving signal deviates from the resonant frequency point more, the vibration intensity will be greatly attenuated. Among them, the vibration direction near the resonant frequency point f ₀ is the Z direction, and the vibration direction near the resonant frequency point f ₀ is the Y direction.

In Fig. 5, when using the asymmetrical waveform as shown in the figure, when the linear motor is driven near the resonant frequency point, due to its mechanical structure and properties, the phenomenon of asymmetrical vibration intensity on both sides will occur. Based on this, a single Gravity effect. Among them, the vibration direction of the motor is controlled by the frequency of the driving signal, and the amplitude of the motor is controlled by adjusting V _pp , that is, the strength of the force simulation effect.

In Figure 6, the PWM waveform is used for driving near the resonant frequency point. Under this kind of waveform driving, the linear motor can generate symmetrical vibration, which can be used to simulate effects such as friction. The vibration direction of the motor is controlled by the frequency of the driving signal, and the amplitude of the motor, that is, the strength of the friction simulation, can be controlled by adjusting the duty cycle/pulse width. In the secondary mode, the peak-to-peak value V _pp of the driving voltage is usually 3V.

Figure 7 is a schematic diagram of touch feedback. The host computer performs collision detection according to the positioning information of the electronic pen, judges whether the electronic pen touches a specific area in the three-dimensional space, triggers a touch event, and sends corresponding instructions to the electronic pen through Bluetooth communication , call the corresponding driving waveform in the prefabricated waveform library, and output vibration tactile feedback. The specific pre-stored waveform can be a digital waveform or an analog waveform.

Figure 8 is a schematic diagram of the rotation feedback. The user enters the rotation mode through button operation, and then rotates the electronic pen in a three-dimensional space according to a certain direction, axis and speed according to the prompts of the host computer. At the same time, the host computer displays the interactive content corresponding to the rotation operation. .

Figure 9 is a schematic diagram of rotation feedback. In this legend, it is determined that the main rotation axis is the Z axis, and the direction is clockwise, so as to determine the vibration direction of the two linear motors and their respective force simulation directions, and generate the force simulation effect as shown in the figure. Vibration feedback.

Figure 10 is a schematic diagram of drag feedback. The user enters the rotation mode through key operation, and then drags the electronic pen in the three-dimensional space according to a certain direction and speed according to the prompt of the host computer, and the host computer displays the interactive content corresponding to the drag operation .

Figure 11 is a schematic diagram of drag feedback. In this legend, it is determined that the main drag direction is the Y direction, so as to determine the vibration direction of the linear motor, and generate the friction simulation effect as shown in the figure for vibration feedback.

Claims (4)

1. A three-dimensional touch electronic pen with vibration tactile feedback, comprising a power supply module, a nine-axis acceleration gyroscope sensor, a button module, a microprocessor, an ultrasonic positioning module, a wireless communication module and a vibration module; it is characterized in that: the vibration module : Including linear motor 1 and linear motor 2, which are respectively fixed at both ends of the electronic pen, each motor has two vibration directions, and the vibration module is driven by a microprocessor to realize multi-dimensional vibration feedback. 2. A kind of three-dimensional touch electronic pen with vibration tactile feedback according to claim 1, characterized in that: Nine-axis acceleration gyro sensor: used to extract acceleration and angular velocity signals, including acquiring the linear velocity, angular velocity, linear acceleration, angular acceleration and attitude information of the electronic pen at any time, and transmitting the extracted acceleration and angular velocity signals to the microprocessor ; Button module: the button module is used to provide shortcut functions; Power module: including battery and boost circuit, powering the whole system; Wireless communication module: using Bluetooth and ZigBee, it is used to send the attitude and speed information of the electronic pen to the host computer and receive the control and configuration information sent by the host computer; Microprocessor: Using single-chip microcomputer and DSP, it is used to realize two kinds of vibration drives through storage and dynamic waveform generation of static waveforms, and is also responsible for acceleration gyroscope sensor signal acquisition and processing, Bluetooth communication chip control, key processing, and host computer send and receive data between Ultrasonic positioning module: including an ultrasonic transmitting module, which is used to periodically transmit ultrasonic signals. 3. The vibration feedback control method of a three-dimensional touch electronic pen with vibration tactile feedback as claimed in claim 1, characterized in that, it includes touching, rotating and dragging in three-dimensional pen interaction, wherein: (1) The specific process of touching is as follows: 1), the user normally holds the electronic pen, enters the touch mode through key operation, the positioning signal module starts to emit infrared and ultrasonic signals periodically, and the host computer uses the principle of ultrasonic positioning to obtain the real-time three-dimensional coordinates P _n (x _n ,y _n) of the electronic pen ,z _n ), where n is the current positioning cycle; 2) In each positioning cycle, the upper computer uses the space coordinates of the electronic pen to detect the collision with the virtual object in the three-dimensional space. Let a virtual cubic area M in the space be {m|x _m1 <x<x _m2 , y _m1 <y<y _m2 , z _m1 <z<z _m2 }, if the coordinate P _i (xi _, y _i , z _i ) of the electronic pen is within M in a certain positioning period, it is considered that the electronic pen touches a certain position in the current period. Object, at this time, the host computer sends relevant instructions to the electronic pen, including the command to start vibration and the pre-stored waveform information called. If no collision is detected, the command to stop vibration is sent to the electronic pen. 3) After the electronic pen receives the instruction from the host computer, if it is a vibration start instruction, it will call the waveform corresponding to the current object number from the prefabricated waveform library for output. The driving signal uses a sinusoidal signal, a triangle signal or a PWM signal, and the driving voltage peak The peak value is V _pp , and the frequency is f _x ; if it is a stop vibration command, stop the vibration; 4) If the user exits the touch mode through key operation, the positioning module stops sending positioning signals, and the electronic pen directly stops vibrating; (2) The specific process of rotation is as follows: 1) The user normally holds the electronic pen, enters the rotation mode through key operation, and the host computer sends instructions to the electronic pen to start dynamic generation and output of vibration feedback waveforms; 2) After the electronic pen receives the rotation feedback command, it first processes and judges the data returned by the nine-axis acceleration gyroscope sensor, and generates a dynamic driving waveform on this basis; 3) The three-dimensional actual rotation axis of the electronic pen can be any axis in the three-dimensional space, and can be regarded as the vector sum of the three axial rotations of X, Y, and Z. Therefore, combined with the vibration direction realized by the linear motor, by comparing the X , Y, Z three axial angular velocity to determine the current main axis of rotation, and based on this to select the vibration direction of the linear motor, assume that the angular velocity of the electronic pen around the X, Y, Z axis at this moment is ωx, ωy, ωz, If ωz<ωy, the main rotation axis of the electronic pen is considered to be the Y axis, the vibration direction of the linear motor unit is taken as the Z axis direction, and the frequency of the driving signal is f0; if ωz≥ωy, the main rotation axis of the electronic pen is considered to be the Z axis , taking the vibration direction of the linear motor unit as the Y-axis direction, and the drive signal as the frequency f1; 4) Calculate the modulus of the current angular velocity And according to the following mapping relationship, the peak-to-peak value of the driving signal voltage V _pp is obtained, and the real-time angular velocity is linearly mapped to the peak-to-peak value of the driving voltage, Vpp1=k*ω, Vpp1 is: the voltage calculated according to the linear mapping, k is a proportional coefficient, Setting the driving voltage threshold as V _max , when Vpp1<V _max , Vpp=Vpp1; when Vpp1>V _max , Vpp=V _max ; 5) According to the information of the nine-axis acceleration gyroscope sensor, determine the downward direction of the current main rotation axis, clockwise or counterclockwise, determine the respective force simulation directions of linear motor 1 and linear motor 2 in the electronic pen, and then determine the direction of the drive signal polarity; 6) Output dynamic driving waveform, which is characterized by the vibration direction perpendicular to the main axis of rotation, the vibration intensity is positively correlated with the modulus of the combined angular velocity of the rotation, and the direction of the simulation effect of linear motor 1 and linear motor 2 at both ends is upward to the main rotation axis The direction of rotation is the same to simulate the torque effect during the rotation process; 7) If the rotation mode is exited by key operation, the electronic pen will stop vibrating directly; (3) The specific process of dragging is as follows: 1) The user normally holds the electronic pen, enters the drag mode through button operation, and the host computer sends instructions to the electronic pen to start the dynamic generation and output of the vibration feedback waveform; 2) After the electronic pen receives the drag feedback command, it first processes and judges according to the data returned by the nine-axis acceleration gyroscope sensor, and then generates a dynamic driving waveform on this basis; the driving waveform of the vibration in the drag mode uses a PWM waveform, Adjust frequency, pulse width; 3) The three-dimensional actual translation direction of the electronic pen can be any direction in the three-dimensional space, and can be regarded as the vector sum of translation in the three directions of X, Y, and Z. Therefore, combined with the vibration direction that can be realized by the linear motor, by comparing the X , Y, Z three axial linear velocity to determine the current main translation direction, and based on this to select the linear motor vibration direction, using the acceleration data returned by the nine-axis acceleration gyroscope sensor to integrate the electronic pen at X , the linear velocities in the Y and Z directions are vx, vy, vz respectively, if vz<vy, it is considered that the main dragging direction of the electronic pen is the Y direction, the vibration direction of the linear motor unit is the Y axis direction, and the driving signal frequency is f1; if vz ≥vy means that the main dragging direction of the electronic pen is the Z direction, the vibration direction of the linear motor unit is the Y-axis direction, and the driving signal frequency is f1; 4) Calculate the modulus of the current line speed According to the following mapping relationship, the PWM duty ratio and the driving signal duty ratio DR are obtained, and the threshold value of the driving signal duty ratio is set to DRmax, and the modulus of the real-time closing speed is linearly mapped to the PWM duty ratio, DR1=k* v, DR1 is the duty cycle obtained according to the mapping relationship, k is the proportional coefficient, when DR1<DRmax, DR=DRp1; when DR1≥DRmax, DR=DRmax; 5) Output the dynamic driving waveform, which is characterized by the same direction of vibration as the main dragging direction, and the vibration intensity is positively correlated with the modulus of the dragging line speed, so as to simulate the friction effect during the dragging process; 6) If the user exits the dragging mode through a button operation, the electronic pen stops vibrating directly. 4. The vibration feedback control method of a three-dimensional touch electronic pen with vibration tactile feedback according to claim 3, characterized in that: Touch definition: the user normally holds the electronic pen, enters the touch mode through button operation, and then touches a specific area in the three-dimensional space with the electronic pen according to the prompts of the host computer, and the host computer displays the corresponding touch operation. interactive content; Rotation definition: the user holds the electronic pen normally, enters the rotation mode through button operation, and then rotates the electronic pen in a three-dimensional space according to a certain direction, axis and speed according to the prompts of the host computer, and the host computer displays the interaction corresponding to the rotation operation content; Definition of drag and drop: the user normally holds the electronic pen, enters the rotation mode through button operation, and then drags the electronic pen in the three-dimensional space according to a certain direction and speed according to the prompt of the host computer, and the host computer displays the interaction corresponding to the drag operation content.