Multi-mode adjustable dynamic mechanical stimulation instrument

Abstract

The invention, which relates to the technical field of biomedical engineering, discloses a multi-modal adjustable dynamic mechanical stimulation instrument comprising a driving system and a stimulation system. The driving system comprises a pulse controller, a driver, a motor, a motion converter and a push rod; the pulse controller, the driver and the motor are in communication connection in sequence; an output shaft of the motor is connected with the lower end of the push rod through a motion converter; the motion converter converts rotary motion of the output shaft of the motor into lifting motion of the push rod; the stimulation system comprises a pushing platform and a sample table; the pushing platform is fixedly arranged at the upper end of the push rod, and the sample table is fixedly arranged above the pushing platform; a plurality of replaceable cell culture chambers are arranged on the sample table; replaceable bullet-shaped protrusions are fixedly arranged at the positions, corresponding to the cell culture cavities, of the pushing platform. The output shaft of the motor can drive the push rod to move towards the sample table. Uniform strain distribution can be realized, and multi-modal dynamic mechanical stimulation can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of biomedical engineering, and in particular to a multi-modal adjustable dynamic mechanical stimulation instrument. Background Art

[0002] The mechanical microenvironment has an important impact on the development and regeneration of organ tissues and the proliferation, migration, differentiation and apoptosis of cells at all levels. For example, musculoskeletal tissue cells are subjected to mechanical tensile stress, and periodontal ligament cells are stimulated by chewing force. The dynamic mechanical stimulation device simulates the mechanical environment of cells in the body by applying mechanical stimulation, thereby achieving the regulation of tissue biological processes and explaining the mechanism of mechanical signals in cell physiological and pathological processes. With the development of biomechanics, mechanical stimulation devices have gradually become a hot topic in applied research.

[0003] Currently, most of the existing dynamic mechanical stimulation devices use fixed culture chambers and uniform specifications for mechanical loading of cell culture plates. They cannot adjust the cell culture volume according to experimental requirements, and cannot meet the research requirements of material surface topology, surface hardness, etc. At the same time, the elastic membrane at the bottom of the fixed culture chamber has problems such as uneven strain distribution, which leads to differences in mechanical stimulation of adjacent cells and experimental errors. Dynamic mechanical stimulation devices also have problems such as a single mechanical loading mode and a narrow range of mechanical stimulation frequency, amplitude and force value adjustment. These limitations have seriously restricted in-depth research on biomechanics.

[0004] Therefore, the development of instruments with adjustable culture substrates, uniform strain distribution and multimodal dynamic mechanical stimulation is of great significance to promoting the research on cell mechanical mechanisms and the treatment of related diseases. Summary of the invention

[0005] The purpose of the present invention is to provide a multi-modal adjustable dynamic mechanical stimulation instrument to solve the problems existing in the above-mentioned prior art, with uniform strain distribution and capable of realizing multi-modal dynamic mechanical stimulation.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a multi-modal adjustable dynamic mechanical stimulation instrument, comprising a driving system and a stimulation system; the driving system comprises a pulse controller, a driver, a motor, a motion converter and a push rod; the pulse controller, the driver and the motor are sequentially connected in communication; the pulse controller is used to generate a multi-modal pulse signal, and the motor can generate corresponding multi-modal motion according to the multi-modal pulse signal; the output shaft of the motor is connected to the lower end of the push rod through the motion converter, and the motion converter converts the rotational motion of the output shaft of the motor into the lifting motion of the push rod; the stimulation system comprises a pushing platform and a sample platform; the pushing platform is fixedly arranged at the upper end of the push rod, and the sample platform is fixedly arranged above the pushing platform; a plurality of replaceable cell culture chambers are provided on the sample platform; replaceable bullet-shaped protrusions are fixedly arranged at positions corresponding to each of the cell culture chambers on the pushing platform, and the shape of the position of the bullet-shaped protrusion for contacting the corresponding cell culture chamber is a shape obtained by simulation and capable of applying uniform strain; the output shaft of the motor can drive the push rod to move in a direction close to the sample platform.

[0008] Preferably, the stimulation system further comprises a fixed base, on which a side bracket is fixedly provided, and an upper end of each side bracket is fixedly connected to the sample stage.

[0009] Preferably, the driving system further comprises a DC regulated power supply, and the DC regulated power supply is connected to the pulse controller.

[0010] Preferably, the motor is a stepper motor.

[0011] Preferably, the pushing platform is provided with a plurality of slots, each of which is fixedly inserted with one of the bullet-shaped protrusions.

[0012] Preferably, the motor is fixedly arranged on a three-axis movable platform, and the three-axis movable platform is fixedly arranged on the fixed base.

[0013] Preferably, the pushing platform can achieve a pulling frequency in the range of 0.1 Hz to 127 Hz.

[0014] Preferably, the multimodal pulse signal includes a rectangular wave, a triangular wave, a sine wave and a trapezoidal wave.

[0015] Preferably, the cell culture chambers are arranged in an array, and markers are provided on the sample stage at positions corresponding to the respective cell culture chambers.

[0016] Preferably, a plurality of mounting holes are provided on the fixed base at positions corresponding to each of the side brackets, and the connecting hole at the bottom of the side bracket corresponds to one of the mounting holes.

[0017] Compared with the prior art, the present invention has achieved the following technical effects:

[0018] The multi-modal adjustable dynamic mechanical stimulation instrument provided by the present invention adopts a pulse controller for generating a multi-modal pulse signal, and a driver is arranged between the pulse controller and the motor, and is used to convert the corresponding multi-modal pulse signal into a corresponding current and voltage, thereby realizing a multi-modal motion that controls the speed, direction and running time of the motor, etc., based on the motor driving the push rod to move, the movement amplitude and speed of the push rod correspond to the output movement of the motor, so as to realize the combination with the characteristics of the motor to form a multi-modal adjustable dynamic mechanical stimulation; a replaceable cell culture chamber is adopted, so as to realize the cell culture of different elastic moduli and surface structures The chamber can be adjusted, and replaceable bullet-shaped protrusions are used to achieve the use of bullet-shaped protrusions with different curvatures and contact areas, thereby improving the uniformity of stress distribution, thereby achieving mechanical stimulation of more uniform strain on the cell culture chamber; multiple cell culture chambers are used in conjunction with corresponding multiple bullet-shaped protrusions, and multi-sample parallel experiments can be carried out simultaneously; the overall synchronization can ensure the uniformity of mechanical stimulation conditions for multi-sample experiments; the finishing structure is simple and exquisite, the operation is efficient and convenient, it can flexibly adapt to various experimental needs, stably provide mechanical stimulation, and significantly improve the experimental efficiency and the accuracy of the results, and it has important scientific research application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A schematic diagram of the overall structure of the multi-modal adjustable dynamic mechanical stimulation instrument provided by the present invention;

[0021] Figure 2 A schematic diagram of the structure of a sample stage and a side bracket in the multi-modal adjustable dynamic mechanical stimulation instrument provided by the present invention;

[0022] Figure 3 An exploded view of the structure of the driving platform and each bullet-shaped protrusion in the multi-modal adjustable dynamic mechanical stimulation instrument provided by the present invention;

[0023] Figure 4 A schematic diagram of a sinusoidal wave driving signal in a multi-modal adjustable dynamic mechanical stimulation instrument provided by the present invention;

[0024] Figure 5 A schematic diagram of a rectangular wave driving signal in a multi-modal adjustable dynamic mechanical stimulation instrument provided by the present invention;

[0025] Figure 6 A schematic diagram of a triangle wave driving signal in a multi-modal adjustable dynamic mechanical stimulation instrument provided by the present invention;

[0026] Figure 7 This is a schematic diagram of a trapezoidal wave driving signal in the multi-modal adjustable dynamic mechanical stimulation instrument provided by the present invention.

[0027] In the figure: 1-DC regulated power supply; 2-pulse controller; 3-driver; 4-stepping motor; 5-push rod; 6-pushing platform; 7-bullet-shaped protrusion; 8-sample table; 9-side bracket; 10-cell culture chamber; 11-fixed base. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] The purpose of the present invention is to provide a multi-modal adjustable dynamic mechanical stimulation instrument to solve the problems existing in the prior art, with uniform strain distribution and capable of realizing multi-modal dynamic mechanical stimulation.

[0030] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] Embodiment 1

[0032] This embodiment provides a multi-modal adjustable dynamic mechanical stimulation instrument, such as Figure 1 to Figure 7As shown, it includes a driving system and a stimulation system; the driving system includes a pulse controller 2 (the pulse controller 2 serves as a control center and is responsible for generating multi-modal pulse signals, such as sine waves, rectangular waves, triangular waves, trapezoidal waves, etc., to adjust the speed, direction and running time of the motor), a driver 3 (converting pulse signals into current and voltage to ensure stable operation of the motor), a motor, a motion converter and a push rod 5; the pulse controller 2, the driver 3 and the motor are connected in communication in sequence; the pulse controller 2 is used to generate multi-modal pulse signals, and the motor can generate corresponding multi-modal motions according to the multi-modal pulse signals; the output shaft of the motor is connected to the lower end of the push rod 5 through a motion converter, and the motion converter converts the rotation of the output shaft of the motor The motion is converted into the lifting motion of the push rod 5; the stimulation system includes a pushing platform 6 and a sample platform 8; the pushing platform 6 is fixedly arranged at the upper end of the push rod 5, and the sample platform 8 is fixedly arranged above the pushing platform 6; a plurality of replaceable cell culture chambers 10 are provided on the sample platform 8; replaceable bullet-shaped protrusions 7 (aimed at optimizing the contact area and improving the uniformity of stress distribution, and the corresponding shape is obtained through simulation) are fixedly arranged at the positions corresponding to each cell culture chamber 10 on the pushing platform 6, and the shape of the position where the bullet-shaped protrusion 7 is used to contact the corresponding cell culture chamber 10 is a shape obtained through simulation that can apply uniform strain; the output shaft of the motor can drive the push rod 5 to move in the direction close to the sample platform 8.

[0033] By adopting a pulse controller 2 for generating a multi-modal pulse signal, a driver 3 is arranged between the pulse controller 2 and the motor, and is used to convert the corresponding multi-modal pulse signal into a corresponding current and voltage, thereby realizing a multi-modal motion that controls the speed, direction and running time of the motor. Based on the movement of the push rod 5 driven by the motor, the movement amplitude and speed of the push rod 5 correspond to the output movement of the motor, so as to realize the combination with the characteristics of the motor to form a multi-modal adjustable dynamic mechanical stimulation; a replaceable cell culture chamber 10 is adopted to realize the adjustment of cell culture chambers with different elastic moduli and surface structures, and cooperate with the use of The replaceable bullet-shaped protrusion 7 can regulate the nominal strain and strain distribution of the base of the cell culture chamber 10 by adjusting the curvature of the bullet-shaped protrusion 7 and the progress of the push rod 5, thereby realizing the regulation of the mechanical stimulation applied to the cells; a plurality of cell culture chambers 10 are used in conjunction with a corresponding plurality of bullet-shaped protrusions 7, so that multi-sample parallel experiments can be carried out simultaneously; the overall synchronization can ensure the uniformity of the mechanical stimulation conditions of the multi-sample experiments; the finishing structure is simple and exquisite, the operation is efficient and convenient, it can flexibly adapt to various experimental needs, stably provide mechanical stimulation, significantly improve the experimental efficiency and the accuracy of the results, and has important scientific research application value.

[0034] Among them, the relevant settings of the drive system are as follows:

[0035] Specifically, the motion converter is an existing structure that can convert the rotational motion of the output shaft of the motor into the linear motion of the push rod 5, which will not be described in detail here; if the motion converter includes a screw and a nut, the screw is fixedly connected to the motor output shaft, that is, the screw and the motor output shaft rotate synchronously, the nut is threadedly connected to the screw, and the nut is fixedly connected to the push rod 5, and a guide device is provided on the nut (the guide device can be a combination of an axial slide groove and a limit slider, such as the motion converter includes a shell, an axial slide groove is provided at the position of the shell corresponding to the axial movement of the nut, a limit slider is fixedly provided on the side wall of the nut, and the limit slider is slidably provided in the axial slide groove), its function is to limit the circumferential rotation of the nut so that it can only move axially along the axial direction of the screw, thereby ensuring the movement accuracy and stability of the push rod 5.

[0036] In the optional scheme of this embodiment, it is more preferred that Figure 1 As shown, the drive system further includes a DC stabilized voltage power supply 1, which is connected to a pulse controller 2. The DC stabilized voltage power supply 1 is responsible for converting input AC power or unstable DC power into an adjustable stable DC voltage.

[0037] In the optional scheme of this embodiment, it is more preferred that the multimodal pulse signal includes rectangular wave, triangular wave, sine wave and trapezoidal wave. It supports the selection and adjustment of multiple waveform drive signals, and can optimize the operation of the motor according to different needs. Among them, the rectangular wave is suitable for fast response application scenarios, the triangular wave helps to reduce vibration, and the sine wave can significantly reduce noise and vibration, ensuring high-precision control. By optimizing current distribution and adjusting the control algorithm, the system can not only improve the performance and stability of the motor, but also reduce the startup shock and extend the life of the equipment.

[0038] In the optional solution of this embodiment, it is more preferred that the motor is a stepper motor 4. The stepper motor 4 is used to meet the precise control requirements of different experiments, and the rotation of the motor directly affects the motion characteristics of the push rod 5.

[0039] In the optional scheme of this embodiment, it is more preferred that the motor is fixedly arranged on the three-axis mobile platform, and the three-axis mobile platform is fixedly arranged on the fixed base 11. The use of the three-axis mobile platform can ensure that each bullet-shaped protrusion on the driving platform 6 accurately corresponds to the sample position of the corresponding cell culture chamber 10; the fixed base 11 can ensure the structural stability of the entire device.

[0040] In the optional solution of this embodiment, it is more preferred that the pulling frequency range that the pushing platform 6 can reach is 0.1 Hz to 127 Hz.

[0041] Among them, the relevant settings of the stimulation system are as follows:

[0042] In the optional scheme of this embodiment, it is more preferred that Figure 1 As shown, the stimulation system further includes a fixed base 11 , on which side brackets 9 are fixedly disposed, and the upper end of each side bracket 9 is fixedly connected to the sample stage 8 .

[0043] In the optional scheme of this embodiment, it is more preferred that Figure 1 and Figure 3 As shown, a plurality of slots are provided on the pushing platform 6, and a bullet-shaped protrusion 7 is fixedly inserted into each slot.

[0044] In the optional scheme of this embodiment, it is more preferred that the cell culture chambers 10 are arranged in an array (applying parallel stimulation to each tissue cell to build a modular and standardized stimulation platform), and markers are provided at the position corresponding to each cell culture chamber 10 on the sample table 8.

[0045] In the optional scheme of this embodiment, it is more preferred that Figure 1 As shown, a plurality of mounting holes are provided on the fixed base 11 at positions corresponding to each side bracket 9 , and the connecting hole at the bottom of the side bracket 9 corresponds to one of the mounting holes.

[0046] Among them, about other related settings description:

[0047] Specifically, the mechanical stimulation frequency, amplitude and waveform are controlled by adjusting the parameters of the pulse controller 2, thereby providing an efficient and convenient mechanical stimulation platform for tissue cell culture and differentiation.

[0048] Specifically, by using a stepper motor 4 and an adapted control drive system, key parameters of the motor motion process (such as speed, direction, start and stop) and motion mode (continuous, intermittent, etc.) can be flexibly and accurately adjusted during the experiment. Through multi-modal drive, it can meet diverse experimental needs.

[0049] Specifically, through high-precision control mechanisms and multi-modal functionalities, the magnitude and frequency of applied force can be accurately adjusted, including but not limited to the movement speed of the push rod 5 and the dwell time at a positioning point during reciprocating motion, etc. The device is suitable for tensile stress loading of cells, and its rapid response capability and high adjustability can significantly improve the efficiency of experimental operations.

[0050] Specifically, when in use, connect the external power cord of the input power socket to the stable power supply voltage socket, press the power switch, and pneumatically adjust the DC regulated power supply 1. According to actual needs, adjust the voltage adjustment encoder and the current adjustment encoder to set the required voltage and current, and judge whether the DC regulated power supply 1 provides stable voltage normally by observing the constant voltage status indicator and the constant current status indicator. In this way, the stable DC voltage provided by the regulated power supply provides power for the normal operation of the pulse controller 2.

[0051] The output signal terminal of the pulse controller 2 (usually a group of wiring terminals or plugs) is connected to the input terminal of the driver 3 for transmitting the generated pulse signal to control the speed and direction of the motor.

[0052] Driver 3 receives pulse signals sent by pulse controller 2, which are used to adjust the running state of the motor. Pulse controller 2 transmits pulse signals to driver 3 through signal lines to ensure that driver 3 can adjust output current and voltage according to instructions. Driver 3 also requires power and usually shares power input with pulse controller 2.

[0053] The driver 3 converts the received pulse signal into current and voltage, and transmits it to the motor through the wire, ensuring that the motor can obtain stable current and voltage.

[0054] A coupling may also be provided on the output shaft of the motor, and connected to the push rod 5 via a motion converter. In this way, the rotational motion of the motor can be effectively converted into the linear reciprocating motion of the push rod 5.

[0055] The motor is fixed to the three-axis mobile platform through a base to ensure that it remains stable during operation.

[0056] The push rod 5 is precisely docked and firmly fixed to the stimulation system to ensure that the bullet-shaped protrusion 7 is accurately embedded in the corresponding position of the sample stage 8 and is reliably connected. The sample stage 8 is fixed to the fixed base 11 through the side bracket 9, which is intended to ensure the stability and accuracy of the sample stage 8 so that the position of the culture area can be accurately aligned with the bullet-shaped protrusion 7 on the stimulation system. This alignment is crucial because it ensures that the experimental sample can be in the correct position when subjected to dynamic mechanical stimulation.

[0057] After the DC regulated power supply 1 is activated and started, the pulse controller 2 and the driver 3 work together to precisely control the motor to achieve the output of a variety of waveform drive signals. By precisely controlling the frequency, amplitude and waveform characteristics of the input signal, the stepper motor 4 can move according to different waveform drive signals, thereby achieving precise control. Common waveforms include rectangular waves, triangular waves, sine waves, etc., each of which has its own unique characteristics and application scenarios.

[0058] like Figure 5 As shown: by adjusting the pulse controller 2 to change the pulse frequency, the speed of the stepper motor 4 is accurately controlled, thereby generating a rectangular wave drive signal. This method is suitable for application scenarios with high requirements for fast response and basic control.

[0059] like Figure 6 As shown: by modulating the drive system and combining the control algorithm of the driver 3, a triangular wave signal is generated, which can promote the smooth start of the motor and reduce vibration, thereby making the motor run more smoothly.

[0060] like Figure 4 As shown in the figure: by finely adjusting the differential parameters of the driver 3, the current is precisely controlled, and the current is applied to each winding of the stepper motor 4 according to the sine function waveform to form a sine wave drive signal. The sine wave drive method can significantly reduce the vibration and noise during the operation of the motor due to its smooth characteristics, so it is particularly suitable for application scenarios that require precise positioning and high-precision control.

[0061] These motion patterns are a critical part of experimental design because they can simulate specific dynamic mechanical stimuli and thus exert the desired mechanical effects on the experimental specimen.

[0062] At the same time, the bullet-shaped protrusion 7 will be displaced in the vertical direction accordingly, and this displacement is synchronized with the linear reciprocating motion of the push rod 5, ensuring that the experimental sample can receive accurate dynamic mechanical stimulation. The application of this stimulation can simulate the mechanical environment experienced by organisms in the natural environment, thereby studying the response of cells under mechanical stimulation.

[0063] Through the above steps, the entire experimental system can effectively simulate the required dynamic mechanical environment, providing a reliable platform for studying the physiological responses of cells under specific mechanical stimuli.

[0064] The design of the push rod 5 takes mechanical properties into consideration to ensure that force can be effectively transmitted and uniform mechanical stimulation can be generated.

[0065] The mobile platform supports the overall structure of the motor and the push rod 5 through the precise screw transmission system of the three-axis mobile platform, ensuring that the motor and the push rod 5 can remain stable during the movement.

[0066] The sample stage 8 is used to firmly fix the biological material or cell sample to be tested. It is intended to ensure that the sample will not be displaced or fall off during the application of mechanical stimulation, and the cell culture sample chamber can be replaced and customized to achieve the regulation of the bottom surface structure and mechanical properties. The morphological design of the replaceable bullet-shaped protrusion 7 can adjust the applied strain to ensure that the applied force can be evenly distributed, thereby avoiding experimental errors caused by excessive local stress.

[0067] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A multi-modal adjustable dynamic mechanical stimulation instrument, characterized in that: Including drive system and stimulation system; The drive system includes a pulse controller, a driver, a motor, a motion converter and a push rod; the pulse controller, the driver and the motor are sequentially connected in communication; the pulse controller is used to generate a multi-modal pulse signal, and the motor can generate corresponding multi-modal motion according to the multi-modal pulse signal; the output shaft of the motor is connected to the lower end of the push rod through the motion converter, and the motion converter converts the rotational motion of the output shaft of the motor into the lifting motion of the push rod; The stimulation system comprises a pushing platform and a sample platform; the pushing platform is fixedly arranged at the upper end of the push rod, and the sample platform is fixedly arranged above the pushing platform; the sample platform is provided with a plurality of replaceable cell culture chambers; a replaceable bullet-shaped protrusion is fixedly arranged at a position corresponding to each of the cell culture chambers on the pushing platform, and the shape of the position where the bullet-shaped protrusion is used to contact the corresponding cell culture chamber is a shape obtained by simulation and capable of applying uniform strain; The output shaft of the motor can drive the push rod to move toward the direction close to the sample stage.

2. The multi-modal adjustable dynamic mechanical stimulation instrument according to claim 1, characterized in that: The stimulation system further comprises a fixed base, on which a side bracket is fixedly arranged, and an upper end of each side bracket is fixedly connected to the sample stage.

3. The multi-modal adjustable dynamic mechanical stimulation instrument according to claim 1, characterized in that: The driving system also includes a DC regulated power supply, which is connected to the pulse controller.

4. The multi-modal adjustable dynamic mechanical stimulation instrument according to claim 1, characterized in that: The motor is a stepping motor.

5. The multi-modal adjustable dynamic mechanical stimulation instrument according to claim 1, characterized in that: The pushing platform is provided with a plurality of slots, each of which is fixedly inserted with a bullet-shaped protrusion.

6. The multi-modal adjustable dynamic mechanical stimulation instrument according to claim 2, characterized in that: The motor is fixedly arranged on the three-axis mobile platform, and the three-axis mobile platform is fixedly arranged on the fixed base.

7. The multi-modal adjustable dynamic mechanical stimulation instrument according to claim 1, characterized in that: The pushing platform can achieve a pulling frequency range of 0.1 Hz to 127 Hz.

8. The multi-modal adjustable dynamic mechanical stimulation instrument according to claim 1, characterized in that: The multi-mode pulse signal includes a rectangular wave, a triangular wave, a sine wave and a trapezoidal wave.

9. The multi-modal adjustable dynamic mechanical stimulation instrument according to claim 1, characterized in that: The cell culture chambers are arranged in an array, and markers are provided on the sample stage at positions corresponding to the cell culture chambers.

10. The multi-modal adjustable dynamic mechanical stimulation apparatus according to claim 2, characterized in that: The fixed base is provided with a plurality of mounting holes at positions corresponding to the side brackets, and the connecting hole at the bottom of the side bracket corresponds to one of the mounting holes.

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