Magnetic resonance brushing tactile stimulation system

Abstract

The utility model discloses a magnetic resonance brush motion tactile stimulation system, including peripheral drive and control module, action execution module and stimulation module, the peripheral drive and control module includes FPGA, the FPGA is connected with motor servo driver, action execution module includes linear motor and Hall sensor, and the linear motor is connected with the Hall sensor. The linear motor is connected with the motor servo driver, the Hall sensor is connected with the FPGA, the stimulation module comprises a transmission unit and a stimulation unit, the linear motor is connected with the transmission unit, and the transmission unit is connected with the stimulation unit. The tactile stimulation device can be quickly installed and deployed and is used for applying tactile stimulation to a subject, and the stimulation mode can be highly self-defined. And the system has extremely fast time response, supports high-time-resolution recording, and can be used for tactile psychological physical experiments of different parts and tactile-related human brain activity researches.

Description

Technical Field

[0001] This invention relates to the field of experimental technology for functional magnetic resonance imaging (fMRI) tasks, and particularly to a brushing tactile stimulation system for magnetic resonance imaging. Background Technology

[0002] In neuroscience research, functional magnetic resonance imaging (fMRI) has become a high spatiotemporal resolution tool for revealing human brain activity. fMRI can capture dynamic changes in the brain on a millisecond timescale while providing millimeter-level spatial resolution, allowing researchers to observe the activity of different brain regions under various tasks or stimuli. Among existing MRI-compatible stimulation devices, common types include pneumatic, hydraulic, and optical. Pneumatic devices typically use changes in air pressure to drive mechanical components for stimulation, exhibiting low electromagnetic interference, but may suffer from slow response speed and low control precision. Hydraulic devices utilize fluid pressure to drive moving parts, providing significant force output, but also exhibiting significant inertia and hysteresis, and requiring a demanding operating environment. Optical devices utilize the conduction properties of light, suitable for specific stimulation needs, but their application range and force control are relatively limited.

[0003] With technological advancements, high temporal resolution fMRI has gradually emerged. High temporal resolution fMRI can more accurately capture the temporal sequence changes of neural activity, which is of great significance for studying rapid interactions and dynamic network connections between different brain regions. It provides more detailed dynamic information on brain function than traditional fMRI, revealing more complex patterns of neural activity. However, the current market lacks high temporal accuracy somatic tactile stimulation systems, which severely limits research on tactile brain activity in humans and small animals. Spatial constraints in the MRI environment and compatibility issues between strong magnetic fields and radio frequency fields are major challenges in realizing such systems. Utility Model Content

[0004] To address the problems of inconvenient installation and low timing accuracy of tactile stimulation systems caused by the limited internal space and complex electromagnetic environment of magnetic resonance imaging (MRI) machines, this invention proposes a brushing tactile stimulation system for MRI machines, thus solving the aforementioned problems.

[0005] This application discloses a magnetic resonance brushing tactile stimulation system, including a peripheral driving and control module, an action execution module, and a stimulation module. The peripheral driving and control module includes an FPGA, which is connected to a motor servo driver. The action execution module includes a linear motor and a Hall sensor. The linear motor is connected to the motor servo driver, and the Hall sensor is connected to the FPGA. The stimulation module includes a transmission unit and a stimulation unit. The linear motor and the transmission unit are connected, and the transmission unit and the stimulation unit are connected.

[0006] Preferably, the FPGA model is Xilinx 7020.

[0007] Preferably, the motion execution module includes a shield, the linear motor is disposed inside the shield, and the Hall sensor is disposed on the outer surface of the shield.

[0008] Preferably, the transmission unit includes a transmission shaft, a flexible sleeve is provided on the outside of the transmission shaft, a fixed base is provided below the flexible sleeve, and the transmission shaft is connected to a linear motor.

[0009] Preferably, a plurality of fixed bases are provided below the flexible sleeve.

[0010] Preferably, the stimulation unit includes a brush and a fixed bracket for supporting the brush, the brush being connected to a drive shaft.

[0011] Preferably, the shielding cover is made of copper.

[0012] Preferably, the flexible sleeve and drive shaft are made of polytetrafluoroethylene, the fixed base and fixed bracket are made of ABS engineering plastic, and the brush is made of nylon.

[0013] Preferably, it includes a hand fixing device, which includes a hand base and a fixing platform. The upper surface of the hand base is provided with a palm-shaped groove, and the fixing platform is provided with fixing holes for connecting the fixing base. A slide rail and a fixing knob are provided on the fingertip side of the palm-shaped groove on the hand base, and the fixing platform is connected to the hand base by the slide rail and the fixing knob.

[0014] Preferably, it includes a transmission positioning unit for connecting multiple transmission units. The transmission positioning unit includes a hollow housing, and the transmission shafts of two adjacent transmission units are connected in the housing. Adjustment knobs are provided at both ends of the housing, and an observation window is provided in the middle of the housing. A scale is provided below the observation window.

[0015] The beneficial effects of this utility model are:

[0016] (1) This utility model can be quickly installed and deployed in different magnetic resonance experimental environments to apply tactile stimulation to the subject. The stimulation form is brushing, and the frequency and intensity of the stimulation can be adjusted. The stimulation site can be selected from the subject's fingers, palms, toes, soles, face and torso, etc. The stimulation mode can be highly customized.

[0017] (2) This utility model has an extremely fast time response and supports high time resolution recording, enabling it to conduct tactile psychophysical experiments on different parts of the body and research on human brain activity related to touch. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the magnetic resonance brushing tactile stimulation system according to an embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of the action execution module structure according to an embodiment of the present utility model;

[0020] Figure 3 This is a schematic diagram of the transmission unit structure according to an embodiment of the present utility model;

[0021] Figure 4 This is a schematic diagram of the secondary unit structure of an embodiment of the present utility model;

[0022] Figure 5 This is a schematic diagram of the hand fixing device according to an embodiment of the present utility model;

[0023] Figure 6 This is a schematic diagram of the transmission positioning unit device according to an embodiment of the present utility model;

[0024] Figure 7 This is a schematic diagram illustrating a specific application scenario of an embodiment of the present utility model.

[0025] Figure label:

[0026] 101-FPGA, 102-Motor servo driver, 201-Linear motor, 202-Shielding cover, 203-Hall sensor, 204-Connection hole, 205-Fixed plate, 301-Flexible sleeve, 302-Drive shaft, 303-Fixed base, 304-Brush, 305-Fixed bracket, 401-Hand base, 402-Groove, 403-Slide rail, 404-Fixed knob, 405-Fixed platform, 406-Fixed hole, 501-Housing, 502-Observation window, 503-Adjustment knob, 6-Magnetic resonance scanner, 7-Test bed. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided with reference to the accompanying drawings and embodiments.

[0028] This application discloses a magnetic resonance brushing tactile stimulation system, such as... Figure 1 As shown, the system includes a peripheral drive and control module, an action execution module, and a stimulation module. The peripheral drive and control module includes an FPGA 101 and a motor servo driver 102. In this embodiment, the FPGA 101 is a Xilinx 7020. The FPGA 101 and the motor servo driver 102 are connected via a copper alloy RS232 electromagnetic compatibility shielded cable. The FPGA 101 is connected to the scanning trigger electrical signal of the magnetic resonance imaging instrument through an I / O port.

[0029] like Figure 2 As shown, the motion execution module includes a linear motor 201, a shielding cover 202, and a Hall sensor 203. The linear motor 201 is disposed inside the shielding cover 202, and the Hall sensor 203 is disposed on the outer surface of the shielding cover 202. The shielding cover 202 is made of copper and has a connection hole 204 on one side for connecting to the stimulation module. The linear motor 201 is connected to the motor servo driver 102 via a copper alloy RS232 electromagnetic compatibility shielded cable, and the Hall sensor 203 is connected to the FPGA 101 via a copper alloy RS232 electromagnetic compatibility shielded cable. The linear motor 201 executes precise movements based on signals from the peripheral drive and control module unit, transmitting the generated motion to the stimulation module. The Hall sensor 203 monitors the magnetic field strength in real time.

[0030] The stimulation module includes a transmission unit and a stimulation unit. A linear motor 201 is connected to the transmission unit, and the transmission unit is also connected to the stimulation unit. For example... Figure 3 As shown, the transmission unit includes a transmission shaft 302, which is connected to a linear motor 201 through a connecting hole 204 on one side of a shield 202. A flexible sleeve 301 is provided outside the transmission shaft 302. The flexible sleeve 301 is shorter than the transmission shaft 302, and neither end of the transmission shaft 302 is covered by the flexible sleeve 301. A fixed base 303 is provided below the flexible sleeve 301. When brushing stimulation is generated, the axial reciprocating motion of the linear motor 201 in the motion execution module may cause unnecessary displacement of the flexible sleeve 301 in the transmission unit. This displacement will affect the transmission shaft 302's accurate transmission of the motion to the brush 304, thus affecting the precise presentation of the stimulation. By setting multiple fixed bases 303, the relative positions of the flexible sleeve 301, the linear motor 201, and the brush 304 are fixed to eliminate these unnecessary displacements. Therefore, a fixed base 303 can be provided in the middle section of the flexible sleeve 301, at the end of the flexible sleeve 301 near the brush 304, and at the end of the flexible sleeve 301 near the linear motor 201. Figure 2 As shown, a protruding fixed plate 205 is provided at the lower part of the shield 202 of the action execution module. The fixed plate 205 is provided with mounting holes, and the bottom of the fixed base 303 is provided with holes corresponding to the mounting holes. The fixed base 303 can be fixed to the fixed plate 205 by bolts.

[0031] like Figure 4As shown, the stimulation unit includes a brush 304 and a fixed bracket 305 for supporting the brush 304. The upper end of the fixed bracket 305 has a hollow structure, allowing the drive shaft 302 to pass through and connect to the brush 304. The flexible sleeve 301 and the drive shaft 302 are made of polytetrafluoroethylene (PTFE). PTFE has excellent heat and chemical corrosion resistance, as well as excellent tensile strength, enabling it to withstand large mechanical stresses without breakage or permanent deformation. Furthermore, PTFE has flexibility and low damping characteristics. Its flexibility allows the positioning system to bend freely and flexibly arrange itself in the magnetic resonance environment according to experimental needs, adapting to various installation requirements within the magnetic resonance chamber without affecting performance. Its self-lubricating properties result in an extremely low surface friction coefficient, reducing friction during use and thus lowering wear and maintenance requirements. The fixed base 303 and the fixed bracket 305 are made of ABS engineering plastic, while the brush 304 is made of nylon.

[0032] Furthermore, to ensure precise contact between the stimulation unit and the human hand, the following additions were made based on the above embodiments: Figure 5 The hand fixation device shown includes a hand base 401 and a fixing platform 405. The upper surface of the hand base 401 has a palm-shaped groove 402. The hand base 401 is 3D printed from ABS material. Custom grooves 402 of different sizes and shapes are provided to guide the hand to remain stationary within the groove. The fixing platform 405 has fixing holes 406. The bottom of the fixing base 303 has corresponding holes, allowing the fixing base 303 to be fixed to the fixing platform 405 with bolts, ensuring stable installation of the stimulation module. A slide rail 403 and a fixing knob 404 are provided on the fingertip side of the palm-shaped groove 402 on the hand base 401, connecting the fixing platform 405 to the hand base 401 via the slide rail 403 and the fixing knob 404. The hand fixing device secures the transmission unit and the brush 304, and its position can be adjusted via the slide rail 403 and the fixing knob 404 according to the different areas of the hand being stimulated, ensuring that the brush 304 can stably provide brushing stimulation to the hand during the stimulation process.

[0033] Furthermore, because the flexible sleeve 301 and the drive shaft 302 in the transmission unit have different degrees of bending during installation, the internal drive shaft 302 and the external flexible sleeve 301 will exhibit different length differences. The main reason for this length difference lies in the difference between their inner and outer diameters: in the bent state, the inner diameter of the drive shaft 302 is smaller and less affected by bending, while the outer diameter of the flexible sleeve 301 is larger and more significantly affected by bending. Since their bending radii are inconsistent, their effective lengths during curling are different, thus affecting transmission accuracy and consistency. To ensure that the system can accurately and stably present the target stimulus each time it is installed in the magnetic resonance experimental environment, multiple transmission units are connected, and additional elements are added between the transmission units, such as... Figure 6 The transmission positioning unit shown is made of rigid ABS material and features an observation window and scale. The transmission positioning unit includes a hollow housing 501. The drive shafts 302 of two adjacent transmission units are connected within the housing 501. Adjustment knobs 503 are located at both ends of the housing 501, and an observation window 502 is located in the middle of the housing 501. A scale is located below the observation window 502. The transmission positioning unit is secured to the drive shaft 302 using the adjustment knobs 503 and a threaded connection device, allowing the transmission unit to accurately guide the brush 304 of the stimulation module to the target stimulation area. Furthermore, the connection between the drive shafts 302 can be designed with a snap-fit ​​mechanism, which, combined with the scale indication below the observation window 502, further enhances the convenience and accuracy of installation and adjustment.

[0034] In a specific embodiment, such as Figure 7 As shown, in one application scenario, the subject lies supine on the test bed 7 of the MRI scanner 6, with the hand fixation device placed on the test bed, one or both hands resting flat on the device. Inside the MRI scanner 6, the experimenter sends experimental paradigm commands from the MRI control room. The stimulation module on the hand fixation device generates corresponding tactile vibration stimulation, providing precise tactile stimulation to the fingers and palms. The hand fixation device can flexibly adjust the position of the stimulation module according to the different body shapes of the subjects, enabling stimulation of any location on the skin surface, such as toes, soles, face, and torso. Employing a linear motor 201 and a transmission unit made of polytetrafluoroethylene (PTFE) with excellent tensile strength, coupled with an FPGA 101 to process the synchronous trigger signal during MRI scanning, the entire system exhibits extremely fast stimulus output response. The synchronously recorded system response delay is lower than the minimum time resolution in functional MRI (response delay < 10 ms), satisfying the requirements of high time resolution functional MRI experiments and providing a powerful tool for exploring the deep mechanisms of human brain activity related to somatic sensation.

[0035] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A magnetic resonance brushing tactile stimulation system, characterized in that, The device includes a peripheral drive and control module, an action execution module, and a stimulation module. The peripheral drive and control module includes an FPGA (101) connected to a motor servo driver (102). The action execution module includes a linear motor (201) and a Hall sensor (203). The linear motor (201) is connected to the motor servo driver (102), and the Hall sensor (203) is connected to the FPGA (101). The stimulation module includes a transmission unit and a stimulation unit. The linear motor (201) is connected to the transmission unit, and the transmission unit is connected to the stimulation unit.

2. The magnetic resonance brushing tactile stimulation system according to claim 1, characterized in that, The FPGA (101) is a Xilinx 7020.

3. The magnetic resonance brushing tactile stimulation system according to claim 2, characterized in that, The action execution module includes a shield (202), the linear motor (201) is disposed inside the shield (202), and the Hall sensor (203) is disposed on the outer surface of the shield (202).

4. The magnetic resonance brushing tactile stimulation system according to claim 3, characterized in that, The transmission unit includes a transmission shaft (302), a flexible sleeve (301) is provided outside the transmission shaft (302), a fixed base (303) is provided below the flexible sleeve (301), and the transmission shaft (302) is connected to a linear motor (201).

5. The magnetic resonance brushing tactile stimulation system according to claim 4, characterized in that, Multiple fixed bases (303) are provided below the flexible sleeve (301).

6. The magnetic resonance brushing tactile stimulation system according to claim 5, characterized in that, The stimulation unit includes a brush (304) and a fixed bracket (305) for supporting the brush (304), the brush (304) being connected to a drive shaft (302).

7. The magnetic resonance brushing tactile stimulation system according to claim 6, characterized in that, The shielding cover (202) is made of copper.

8. The magnetic resonance brushing tactile stimulation system according to claim 7, characterized in that, The flexible sleeve (301) and drive shaft (302) are made of polytetrafluoroethylene, the fixed base (303) and fixed bracket (305) are made of ABS engineering plastic, and the brush (304) is made of nylon.

9. The magnetic resonance brushing tactile stimulation system according to claim 8, characterized in that, The device includes a hand fixing device, which includes a hand base (401) and a fixing platform (405). The upper surface of the hand base (401) is provided with a palm-shaped groove (402). The fixing platform (405) is provided with fixing holes (406) for connecting the fixing base (303). A slide rail (403) and a fixing knob (404) are provided on the fingertip side of the palm-shaped groove (402) on the hand base (401). The fixing platform (405) is connected to the hand base (401) through the slide rail (403) and the fixing knob (404).

10. The magnetic resonance brushing tactile stimulation system according to claim 9, characterized in that, The device includes a transmission positioning unit for connecting multiple transmission units. The transmission positioning unit includes a hollow housing (501). The transmission shafts (302) of two adjacent transmission units are connected in the housing (501). Adjustment knobs (503) are provided at both ends of the housing (501). An observation window (502) is provided in the middle of the housing (501). A scale is provided below the observation window (502).

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