A micro-motion early warning liquid crystal sensor, a preparation method and application thereof

Abstract

The application discloses a micro-movement early warning liquid crystal sensor and a preparation method and application thereof. The sensor comprises oppositely arranged upper and lower glass substrates, mutually perpendicular groove arrays are arranged on the opposite inner surfaces of the upper and lower glass substrates, a liquid crystal interlayer is arranged between the upper and lower glass substrates, and the liquid crystal interlayer is sealed through a sealing layer. An upper polarizer is arranged on the upper surface of the upper glass substrate, a lower polarizer is arranged on the lower surface of the lower glass substrate, and a backlight plate is arranged below the lower polarizer. The application realizes micro-movement early warning monitoring of a measured object by utilizing the surface anchoring effect of liquid crystal, can monitor the micro movement of the object through the orientation change degree of the liquid crystal molecules, and further realizes the early warning purpose. The sensor has excellent sensitivity, accuracy and durability, and can realize real-time early warning monitoring.

Description

Technical Field

[0001] This invention relates to the field of sensor technology, specifically to a micro-motion early warning liquid crystal sensor, its preparation method, and its application. Background Technology

[0002] With the deepening of intelligent development, sensors, as an important component of modern technological development, play a vital role. Sensor technology has also evolved from structural sensors and solid-state sensors to intelligent sensors. Intelligent sensors refer to those with certain detection, self-diagnosis, data processing, and adaptive capabilities for external information, and are a product of the combination of microcomputer technology and detection technology. However, from the perspective of industry product structure, traditional sensors still occupy a large market share. Sensor materials have shortcomings such as low sensitivity and limited functionality. In particular, the monitoring of early warning information is mostly done manually, which is inconvenient and the sensor structure is complex, making it difficult to achieve high-sensitivity real-time early warning monitoring. There is a significant shortage of new sensors, and digital, intelligent, and miniaturized products are severely lacking.

[0003] Liquid crystals are organic compounds that exist between solid and liquid states, possessing both the optical properties of solid crystals and the flow properties of liquids, especially nematic liquid crystals. Because nematic liquid crystal molecules readily move freely along their long axis, they exhibit low viscosity and high fluidity. The arrangement and movement of nematic liquid crystal molecules are relatively free, making them highly sensitive to external influences. Liquid crystals exhibit different anchoring types depending on the direction of the applied external force. Currently, this property of liquid crystals can be used to fabricate liquid crystal sensors for specific operating conditions. For example, Chinese invention patent CN109696438A discloses a microfluidic arrayed liquid crystal sensor. By introducing the test liquid while the liquid crystal is fixed rather than suspended and movable, real-time observation and recording of the reaction process in a fixed area can be achieved. However, current liquid crystal sensors cannot monitor the micro-movement of objects. Summary of the Invention

[0004] To address the problems existing in the prior art, this invention provides a micro-motion early warning liquid crystal sensor, its preparation method, and its application. Utilizing the surface anchoring effect of liquid crystals, it achieves early warning monitoring of micro-motion of the measured object. It can monitor the minute movements of the object by detecting changes in the orientation of liquid crystal molecules, thereby achieving the purpose of early warning. The sensor has excellent sensitivity, accuracy, and durability, and can perform real-time early warning monitoring.

[0005] The technical solution of the present invention is as follows:

[0006] In a first aspect of the present invention, a micro-motion early warning liquid crystal sensor is provided, comprising an upper glass substrate and a lower glass substrate disposed opposite to each other, wherein mutually perpendicular groove arrays are provided on the inner surfaces of the upper glass substrate and the lower glass substrate, a liquid crystal interlayer is disposed between the upper glass substrate and the lower glass substrate, the liquid crystal interlayer being sealed by a sealing layer; an upper polarizer is disposed on the upper surface of the upper glass substrate, a lower polarizer is disposed on the lower surface of the lower glass substrate, and a backlight plate is disposed below the lower polarizer.

[0007] In some embodiments of the present invention, the lower surface of the upper glass substrate and the upper surface of the lower glass substrate are both covered with an alignment film, and the alignment direction of the alignment film is consistent with the groove direction on the adjacent substrate.

[0008] In some embodiments of the present invention, the upper glass substrate has a display function, and the display area is equipped with or connected to an early warning monitoring module.

[0009] In some embodiments of the present invention, the side length of the surface groove array is 50-300μm, the interval between adjacent arrays is 20-50μm, and the distance between the boundary array and the edge of the substrate is 2-5mm.

[0010] In some embodiments of the present invention, the thickness of the liquid crystal interlayer is 5-20 μm, and the liquid crystal filled in the liquid crystal interlayer includes thermotropic liquid crystal and lyotropic liquid crystal.

[0011] In some embodiments of the present invention, silicon dioxide beads of a diameter corresponding to the thickness of the liquid crystal interlayer are fixed between the upper glass substrate and the lower glass substrate.

[0012] In a second aspect of the present invention, a method for preparing a micro-motion early warning liquid crystal sensor is provided, comprising the following steps:

[0013] Diamond particles of the same diameter are fixed on a thin film, and the glass substrate is pressed and rubbed back and forth on the thin film several times with constant pressure and speed to obtain a regular array of surface grooves; or, a thin film that induces liquid crystal alignment is covered on the surface of the substrate, and then surface treatment is performed.

[0014] The two treated glass substrates are placed face to face, and the two glass substrates are sealed with a sealing layer, with a liquid crystal injection port reserved.

[0015] Liquid crystal is injected into the interlayer through capillary effect, and left to stand for 5-10 minutes to allow the liquid crystal to fill the entire interlayer.

[0016] Install an early warning monitoring module, polarizer, and backlight panel.

[0017] In some embodiments of the present invention, the diamond particles have a diameter of 10-100 μm and a pressure of 1-5 N / cm. 2The friction speed is 1-5 cm / s, and the number of friction cycles is 5-20.

[0018] In a third aspect of the invention, a method for using a micro-motion early warning liquid crystal sensor is provided. The sensor is installed at a position where an object moves relative to it. As the object being monitored moves slightly, the upper and lower substrates of the sensor move alternately in the parallel direction, causing the liquid crystal to exhibit different orientations. Brightness and color changes are observed through a polarizer, and a monitoring signal of the object being measured is fed back. The degree of brightness and color change depends on the anchoring type and order parameter of the liquid crystal molecules, and the brightness and color changes become more obvious as the moving distance of the object being measured increases.

[0019] In some embodiments of the present invention, the early warning module converts the optical signal into an electrical signal for precise early warning monitoring, specifically including: initializing the early warning module, monitoring the object movement value in real time, determining whether the movement value exceeds the early warning value, and if so, issuing an early warning, resetting after the early warning, and if not, continuing real-time monitoring.

[0020] One or more technical solutions of the present invention have the following beneficial effects:

[0021] The micro-motion early warning liquid crystal sensor provided by this invention utilizes the surface anchoring effect of liquid crystal to achieve early warning monitoring of micro-motion of the measured object. It can detect the minute movement of the object by the degree of change in the orientation of liquid crystal molecules, thereby achieving the purpose of early warning. The sensor has excellent sensitivity, accuracy and durability, and can perform real-time early warning monitoring.

[0022] The micro-motion early warning liquid crystal sensor provided by this invention further improves the accuracy of early warning monitoring by coating the substrate surface with a thin film that induces liquid crystal alignment. It achieves efficient and direct feedback on the micro-movement of the object being detected, providing accurate and sensitive early warnings, overcoming the shortcomings of existing sensors such as limited functionality and low sensitivity. Furthermore, the sensor is simple to manufacture, its size is controllable, it requires no professional personnel, and it is easy to implement.

[0023] The method for preparing a micro-motion early warning liquid crystal sensor provided by the present invention allows for adjustment of the diamond particle size according to the monitoring accuracy requirements, thereby obtaining appropriate sizes with different transmittance and liquid crystal arrangement, and expanding the application range of the prepared sensor.

[0024] The micro-motion early warning liquid crystal sensor provided by this invention offers two modes: coarse early warning monitoring and precise early warning monitoring. These modes can be used to quickly detect the micro-motion of the object to be monitored according to different needs. Attached Figure Description

[0025] Figure 1 is a schematic diagram of the groove array on the surface of the glass substrate of the present invention, wherein Figure 1(a) is a schematic diagram of the groove array on the lower glass substrate and Figure 1(b) is a schematic diagram of the groove array on the upper glass substrate.

[0026] Figure 2 is a schematic diagram of the anchoring types of liquid crystal surfaces: Figure 2(a) represents random planar anchoring, Figure 2(b) represents uniform planar anchoring, Figure 2(c) represents vertical anchoring, and Figure 2(d) represents inclined anchoring.

[0027] Figure 3 This invention relates to the orientation state of liquid crystal molecules before monitoring by the micro-motion early warning liquid crystal sensor.

[0028] Figure 4 This is a schematic diagram of the orientation of liquid crystal molecules under anchoring effect during the monitoring process of the micro-motion early warning liquid crystal sensor of the present invention;

[0029] Figure 5 is a schematic diagram of liquid crystal molecule twisting, wherein Figure 5(a) is a top view of liquid crystal molecule twisting and Figure 5(b) is a side view of liquid crystal molecule twisting.

[0030] Figure 6 This is a flowchart of the early warning process of the present invention.

[0031] In the diagram: 1. Upper polarizer; 2. Upper glass substrate; 3. Upper alignment film; 4. Liquid crystal molecules; 5. Sealing layer; 6. Lower alignment film; 7. Lower glass substrate; 8. Lower polarizer; 9. Backlight panel. Detailed Implementation

[0032] Terminology Explanation: Liquid Crystal Surface Anchoring: This refers to the orientation characteristics of liquid crystal molecules on a surface. Due to surface anchoring, liquid crystal molecules near surfaces with different morphologies have different orientations. Based on the relationship between molecular orientation and surface arrangement, as shown in Figure 2, surface anchoring can be divided into four types: uniform planar anchoring, vertical anchoring, random planar anchoring, and tilted anchoring. The order parameter characterizes the degree of order in the arrangement of liquid crystal molecules.

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0034] Example 1

[0035] In a typical embodiment of the present invention, as shown in FIG1 and Figure 3As shown, a micro-motion early warning liquid crystal sensor is proposed, comprising an upper glass substrate 2 and a lower glass substrate 7 arranged opposite to each other. Both glass substrates have good light transmittance. An array of mutually perpendicular grooves is formed on the opposing inner surfaces of the upper glass substrate 2 and the lower glass substrate 7. A liquid crystal interlayer is disposed between the upper glass substrate 2 and the lower glass substrate 7, and the liquid crystal interlayer is sealed by a sealing layer 5. An upper polarizer 1 is disposed on the upper surface of the upper glass substrate 2, and the polarization direction of the upper polarizer is consistent with the direction of the grooves on the upper glass substrate. A lower polarizer 8 is disposed on the lower surface of the lower glass substrate 7, and the polarization direction of the lower polarizer is consistent with the direction of the grooves on the lower glass substrate, i.e., the polarization directions of the upper and lower polarizers are perpendicular. A backlight plate 9 is disposed below the lower polarizer 8, wherein the backlight plate is a light source device that provides the required light source. The polarizer converts natural light into polarized light, and through the optical rotation effect of the liquid crystal layer, controls whether light can pass through.

[0036] To further improve the accuracy of early warning, the lower surface of the upper glass substrate 2 and the upper surface of the lower glass substrate 7 are both covered with an alignment film. Specifically, the lower surface of the upper glass substrate is covered with an upper alignment film 3, and the upper surface of the lower glass substrate is covered with a lower alignment film 6. The orientation direction of the alignment film is consistent with the direction of the groove on the adjacent substrate.

[0037] Furthermore, the upper glass substrate has a display function, and the display area has a built-in early warning monitoring module. In this embodiment, the early warning monitoring module can use an integrated chip (such as a microelectromechanical system commonly used in sensors) and be packaged together with the sensor. Integrated chip technology is relatively mature, and both internal and external connections are possible. Those skilled in the art can choose according to their needs.

[0038] Furthermore, the surface groove array has a side length of 50-300μm, an adjacent array spacing of 20-50μm, and a boundary array distance of 2-5mm from the substrate edge. Through the above settings, on the one hand, the fault tolerance rate can be increased and the error reduced, and on the other hand, the surface texture can be enhanced to anchor the liquid crystal, preventing the anchoring effect from being affected by too few or too many textures. At the same time, when silicon dioxide beads are placed between the upper glass substrate and the lower glass substrate, a fixed position can be reserved for the silicon dioxide beads.

[0039] Furthermore, the thickness of the liquid crystal interlayer is 5-20 μm, and the liquid crystal filled in the liquid crystal interlayer includes thermotropic liquid crystals and lyotropic liquid crystals, such as 5CB liquid crystal (4-cyano-4'-pentylbiphenyl), 8CB liquid crystal (4'-n-octyl-4-cyanobiphenyl), and E7 liquid crystal, etc. Thermotropic and lyotropic liquid crystals are injected into the interlayer through a pre-reserved port via capillary action in isotropic and nematic phases, respectively.

[0040] Furthermore, the sealing layer is made of a flexible and elastic material, such as PDMS or Mylar polyester film, which can be deformed under stress and return to its original shape when no external force is applied.

[0041] To ensure that the liquid crystal interlayer has a regular thickness, silicon dioxide beads of a corresponding diameter are fixed between the upper and lower glass substrates to prevent the distance between the upper and lower substrates from changing during the deformation of the sensor.

[0042] In practice, the size of the glass substrate is adjusted according to the moving distance of the object to be tested. Similarly, the substrate material can be replaced with other light-transmitting materials according to the actual situation, and a certain degree of surface treatment can be performed.

[0043] The working principle of the micro-motion early warning liquid crystal sensor provided in this embodiment is as follows:

[0044] When the liquid crystal sensor is used to monitor the micro-movement of an object, the liquid crystal layer, initially aligned (or not aligned) with the same molecular orientation, moves with the object. Different anchoring effects occur due to variations in the surface texture of the glass substrate, altering the orientation of the liquid crystal molecules and thus changing the light transmittance. Brightness and color changes can be observed through a polarizing device, providing feedback on the monitoring signal of the object. The degree of brightness and color change depends on the anchoring type and order parameter of the liquid crystal molecules, and these changes become more pronounced as the distance the object moves increases. The principle lies in the perpendicular array of grooves on the two substrates. Liquid crystal molecules near the substrate surface align along the direction of the grooves. Due to the inherent viscosity of the liquid crystal, the liquid crystal molecules between the two substrates are forced into a twisted state. Because the liquid crystal molecules are twisted, light passing through them is also twisted. When the liquid crystal molecules are subjected to external forces, interaction forces are generated between them, causing the molecules to rearrange. Light in this state, after passing through the lower polarizer, is no longer subject to the twisting transmission of light by the liquid crystal molecules. However, polarizers only allow light components in a fixed direction to pass through. The polarization direction of the upper polarizer is perpendicular to that of the lower polarizer, thus preventing light from passing through. When the object moves at different degrees (or times), the degree of rearrangement of the liquid crystal molecules also varies, thereby controlling the degree of light deflection to obtain differences in brightness and color, achieving the purpose of early warning monitoring. Backlight panel manufacturing and liquid crystal display technology are already widely used, so they will not be elaborated upon further.

[0045] Example 2

[0046] In a typical embodiment of the present invention, a method for fabricating a micro-motion early warning liquid crystal sensor is proposed, comprising the following steps:

[0047] Diamond particles of the same diameter are fixed on a thin film, and a glass substrate is pressed and rubbed back and forth on the thin film several times with constant pressure and speed to obtain a regular array of surface grooves.

[0048] To further improve the accuracy of early warning monitoring, a thin film that induces liquid crystal alignment can be coated on the substrate surface before surface treatment.

[0049] Place the two treated glass substrates face to face and seal them with a sealing layer.

[0050] Liquid crystal is injected into the interlayer through capillary effect, and left to stand for 5-10 minutes to allow the liquid crystal to fill the entire interlayer.

[0051] Install an early warning monitoring module, polarizer, and backlight panel.

[0052] Specifically, the diamond particles have a diameter of 10-100 μm and a pressure of 1-5 N / cm. 2 The friction speed is 1-5 cm / s, and the number of friction cycles is 5-20. Before and after treatment, the glass substrate needs to be chemically cleaned and ultrasonically cleaned, and then dried with nitrogen to remove residual particles. Acetone, ethanol, deionized water, etc. can be used for chemical cleaning.

[0053] In some embodiments of this example, the particle size of the diamond particles can be adjusted according to the monitoring accuracy requirements to obtain appropriate sizes with different light transmittance and liquid crystal arrangement.

[0054] Example 3

[0055] In a typical embodiment of the present invention, a method for using a micro-motion early warning liquid crystal sensor is proposed. The sensor is installed at the position where the object moves relative to it. When the object moves relative to it, the sensor deforms, and the upper and lower substrates move alternately in the parallel direction, causing the liquid crystal to have different orientations. The changes in brightness and color are observed through a polarizer, and the monitoring signal of the object being measured is fed back. The degree of change in brightness and color depends on the anchoring type and order parameter of the liquid crystal molecules, and the changes in brightness and color become more obvious as the moving distance of the object being measured increases.

[0056] Specifically, in applications like flange connections or flange joints commonly found in mechanical equipment, it's necessary to monitor the bolts on the flange during operation to prevent equipment malfunctions caused by loose bolts. The upper and lower base plates of a sensor are fixed to the flange and bolts respectively. When a bolt loosens, the upper base plate of the sensor moves accordingly. Because there are silica beads separating the base plates, the upper base plate moves in a direction parallel to the lower base plate. Furthermore, in some experimental equipment or precision instruments containing guide rails, it's also necessary to ensure that samples are not damaged by the slight movement of the guide rails during operation. Fixing the sensor in the same way allows for real-time monitoring of changes in the guide rail position.

[0057] Currently used displacement sensors have relatively limited functionality and stringent installation requirements, such as requiring large measurement spaces, low resolution, and being only suitable for static measurements rather than dynamic monitoring, thus restricting their application. The sensor provided by this invention, however, does not have these limitations.

[0058] The early warning module converts optical signals into electrical signals for precise early warning monitoring, such as... Figure 6 As shown, the specific steps include: initializing the early warning module, monitoring the object movement value in real time, determining whether the object movement value exceeds the early warning value, issuing an early warning if so, resetting the module after the early warning, and continuing real-time monitoring if not.

[0059] As shown in Figure 5, in the initial state, because the groove arrays on the two substrates are perpendicular to each other, the liquid crystal molecules near the substrate surface align along the direction of the surface grooves. Due to the inherent viscosity of liquid crystal, the liquid crystal molecules located between the two substrates are forced into a twisted state. The liquid crystal molecules are in a twisted state, and light passing through them is also twisted. Figure 3 and Figure 4 As shown, when liquid crystal molecules move with the monitored object, they interact with each other. Anchored on the substrate surface, the initial twisted structure of the liquid crystal layer is disrupted, causing the liquid crystal molecules to rearrange. In this state, light passing through the lower polarizer no longer undergoes twisted transmission of polarized light by the liquid crystal molecules. However, the polarizer only allows light components in a fixed direction to pass through; the polarization direction of the upper polarizer is perpendicular to that of the lower polarizer, thus preventing light transmission. When the degree (or number of times) of object movement differs, the degree of rearrangement of the liquid crystal molecules also differs, i.e., the anchoring type (as shown in Figure 2) and the degree and number of light twists vary, resulting in different brightness and colors displayed on the screen, achieving the purpose of early warning monitoring.

[0060] In practical implementation, the liquid crystal sensor of the present invention can provide two modes: coarse early warning monitoring and precise early warning monitoring.

[0061] In coarse warning mode, the approximate distance the object has moved is determined by observing the brightness, color change rate, or frequency of changes in the sensor display area. In situations where accurate warnings are not required, it can quickly provide micro-movement signals of the object being monitored.

[0062] In precise early warning mode, an initial "zero" scale value is preset for the orientation of liquid crystal molecules. When the orientation of the liquid crystal changes, the corresponding monitoring value will also change, and the early warning monitoring module will issue a real-time warning.

[0063] Alternatively, coarse monitoring can be performed by adjusting the settings of the warning module. For example, the warning module will only issue a warning if the brightness or color of the display area changes more than a certain number of times, or if the monitored warning value exceeds the set value. When unattended, the warning module can be remotely controlled via its communication function to achieve sensor detection, self-diagnosis, data storage and processing.

[0064] Given that the orientation modulation of liquid crystal molecules is reversible, this device can be reused.

[0065] The embodiments described above provide a detailed explanation of the technical solution of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, additions, or similar substitutions made within the scope of the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A micro-motion early warning liquid crystal sensor, characterized in that, The device includes an upper glass substrate and a lower glass substrate arranged opposite to each other. The inner surfaces of the upper glass substrate and the lower glass substrate are provided with mutually perpendicular groove arrays. A liquid crystal interlayer is provided between the upper glass substrate and the lower glass substrate, and the liquid crystal interlayer is sealed by a sealing layer. An upper polarizer is provided on the upper surface of the upper glass substrate, a lower polarizer is provided on the lower surface of the lower glass substrate, and a backlight plate is provided below the lower polarizer. The lower surface of the upper glass substrate and the upper surface of the lower glass substrate are both covered with an alignment film, and the alignment direction of the alignment film is consistent with the groove direction on the adjacent substrate; the liquid crystal molecules near the substrate surface are arranged along the direction of the surface groove. A silica bead of the same diameter as the thickness of the liquid crystal interlayer is fixed between the upper and lower glass substrates to prevent the distance between the upper and lower substrates from changing during the deformation of the sensor. The upper and lower substrates of the sensor move alternately in the parallel direction, causing the liquid crystal to have different orientations. The surface groove array has a side length of 50-300μm, an adjacent array spacing of 20-50μm, and a boundary array distance of 2-5 mm from the substrate edge. Through the above settings, the fault tolerance is increased while the surface texture enhances the anchoring effect of the liquid crystal, preventing the anchoring effect from being affected by too few or too many textures. At the same time, when silicon dioxide beads are placed between the upper and lower glass substrates, a fixed position can be reserved for the silicon dioxide beads. Different surface textures of the glass substrate produce different anchoring effects, which changes the orientation of the liquid crystal molecules and thus alters the light transmittance of the liquid crystal. Brightness and color changes can be observed through a polarizing device, providing feedback on the monitoring signal of the object under test.

2. The micro-motion early warning liquid crystal sensor as described in claim 1, characterized in that, The upper glass substrate has a display function, and the display area has a built-in or external early warning monitoring module.

3. The micro-motion early warning liquid crystal sensor as described in claim 1, characterized in that, The thickness of the liquid crystal interlayer is 5-20 μm, and the liquid crystal filled in the liquid crystal interlayer includes thermotropic liquid crystal and lyotropic liquid crystal.

4. A method for preparing a micro-motion early warning liquid crystal sensor as described in any one of claims 1-3, characterized in that, Includes the following steps: Diamond particles of the same diameter are fixed on a thin film, and a glass substrate is pressed and rubbed back and forth on the thin film several times with constant pressure and speed to obtain a regular array of surface grooves. Alternatively, a thin film that induces liquid crystal alignment can be coated onto the substrate surface, followed by surface treatment. A thin film that induces liquid crystal alignment is coated onto the treated surface of the glass substrate; The two treated glass substrates are placed face to face, and the two glass substrates are sealed with a sealing layer, with a liquid crystal injection port reserved. Liquid crystal is injected into the interlayer through capillary effect, and left to stand for 5-10 minutes to allow the liquid crystal to fill the entire interlayer. Install an early warning monitoring module, polarizer, and backlight panel.

5. The method for preparing the micro-motion early warning liquid crystal sensor as described in claim 4, characterized in that, The diamond particles have a diameter of 10-100 μm and a pressure of 1-5 N / cm. 2 The friction speed is 1-5 cm / s, and the number of friction cycles is 5-20.

6. A method of using the micro-motion early warning liquid crystal sensor as described in any one of claims 1-3, characterized in that, The sensor is installed at a position where the object moves relative to it. As the object being monitored moves slightly, the upper and lower substrates of the sensor move alternately in the parallel direction, causing the liquid crystal to have different orientations. The changes in brightness and color are observed through a polarizer, and the monitoring signal of the object being measured is fed back. The degree of change in brightness and color depends on the anchoring type and order parameter of the liquid crystal molecules. Moreover, the changes in brightness and color are more obvious as the moving distance of the object being measured increases.

7. The method of using the micro-motion early warning liquid crystal sensor as described in claim 6, characterized in that, The early warning module converts light signals into electrical signals for precise early warning monitoring. Specifically, it includes: initializing the early warning module, monitoring the object's movement value in real time, determining whether the movement value exceeds the warning value, issuing an early warning if so, resetting the module after the warning, and continuing real-time monitoring if not.

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