568results about How to "No electromagnetic interference" patented technology

The invention relates to a piezoelectric hydraulic linear motor which pertains to the field of mechanical-electrical-hydraulic integration. An inlet of a piezoelectric pump is connected with an accumulator by a pipeline; the accumulator is also connected with a reversing valve by the pipeline; the reversing valve is connected with an outlet of the piezoelectric pump by the pipeline; the reversing valve is also connected with a cavity body of a hydraulic cylinder. The piezoelectric hydraulic linear motor has the advantages of novel structure, being capable of effectively converting the micro-amplitude reciprocating vibration of piezoelectric ceramic to the micro liner motion of a piston of the hydraulic cylinder by utilizing fluid media to transmit power, obtaining relatively large driving power and motion displacement and realizing precise driving and control by a method of accumulating a liquid drop for one time; meanwhile, the piezoelectric hydraulic motor has simple structure and control, small volume and good sealing property and can be applied to marking parts.

The invention relates to a design method used for transmitting DC high-temperature superconducting cable body coaxially and bidirectionally, belonging to the field of power system transmission and transformation; the design method comprises the steps as follows: according to the mechanical characteristic and the radius of enwinding framework of the superconducting strips, parameters of the superconducting cable body such as the enwinding helix angle and the enwinding pitch are determined; the magnetic field distribution of all layers of superconducting cable body are determined according to the operation current, thus determining the critical current on all layers of the cable; according to the critical current and the operation redundancy, iterative calculation is carried out for operation current and the magnetic field, thus finally gaining the critical current, best operation current, enwinding layer number and number of the cables. The designed superconducting cable body increases no enwinding process difficulty and achieves bidirectional transmission of DC current; the utilization ratio of the superconducting strip critical current reaches more than 90%; the quantity and low-temperature heat loss of the superconducting cable low-temperature container are respectively reduced by half. The design method has the advantages of large transmission capability, no loss, compact structure, certain current limiting capability, stable mechanical structure, self-shielding, no electromagnetic interference and the like.

The invention discloses a distributed fiber optic sensing technology and a system for monitoring of deformation of a high arch dam, which relate to the field of crossing of a dam safety monitoring technology and a fiber optic sensing technology and are used for overcoming the defect of a conventional means for the monitoring of the deformation of the high arch dam and filling the blank of using distributed fiber optic sensing for the monitoring of the deformation of a dome dam. Aiming at the characteristics and the difficulties of the dome dam, two kinds of unique curved fiber optic packaging structures, namely, fiber optic monitoring panels in a weakly curved beam type and a micro-bending beam type, are provided. Based on error analysis and curved beam height control-camber beam segmentation construction, excellent performance, high reliability, long service life, convenience and practicability of monitoring of fiber optic deformation are ensured. A convenient and practical layout installation mode in an arch dam and a gallery, a vertical shaft and a footrill of a dam foundation is provided, so that online remote metering on multi-dimensional and large-scale time-space broad coverage of three components (radial horizontal displacement, tangential horizontal displacement and vertical displacement) of internal deformation of the arch dam, the dam foundation and a dam abutment is realized. An optical demodulation instrument is multifunctional and can be used for metering concrete temperature, reservoir water temperature, slit level in front of a dam, reservoir sedimentation and the like.

The invention discloses a device for testing the uniaxial tension mechanical property of a conducting material under high temperature environment, and belongs to the technical field of material mechanical property testing. According to the device, an induction coil is wound by a copper pipe; an upper insulating tension bar is connected with the upper end surface of an upper clamp through an upper insulating spacer; a lower insulating tension bar is connected with the lower end surface of a lower clamp through a lower insulating spacer; when the upper end of a test piece to be tested is clamped at the lower end of the upper clamp, and the lower end of the test piece to be tested is clamped at the upper end of the lower clamp, the induction coil sleeves the outer side of the test piece to be tested at intervals, and the two ends of the induction coil are respectively connected with two high-frequency driving output ends of an induction heating system controller; the temperature testing end of a temperature testing probe remotely tests the temperature of the test piece to be tested; the temperature signal output end of the temperature testing probe is connected with the temperature signal input end of the induction heating system controller. The device adopts induction heating, is small in size of the induction coil, simple to manufacture, is connected with the heating system controller through a bolt, and is convenient to disassemble and relatively quick in temperature rise.

The invention discloses an electric connector. The electric connector comprises an insulation body and multiple conductive terminals which are contained in the insulation body, wherein the insulation body is externally coated with a non-metal shell, and an inserting opening is formed by surrounding the non-metal shell and the insulation body. In such a way, a shell is made from a non-metal material, the electromagnetic interference cannot be caused for the radio frequency of a mobile device, the call quality can be ensured, and thus the defects of the prior art can be overcome. In addition, a grounding terminal is inserted into the tail end of the insulation body, the grounding terminal stretches into the inserting opening and is suspended at the inner wall surface of the non-metal shell, the grounding terminal is contacted with the shell of a USB (Universal Serial Bus) plug when a butt-joint USB plug is inserted in the inserting opening, and thus the grounding function of a metal shell in an original product can be replaced.

A driving circuit includes: a clock signal generating unit, for generating clock signals, where transitions from first level to second level, in each clock signal, trigger a scan driving circuit to generate scanning signals, the transitions from first level to second level are defined as effective signal edges of the clock signals, and an interval between adjacent effective signal edges is defined as a clock time interval; and a control unit, for controlling clock time intervals of each clock signal to be non-identical, the clock time intervals including a first clock time interval and second clock time interval, the second clock time being longer than the first clock time, and the control unit is configured to control the clock time interval to be the second clock time interval at least once during displaying one frame of image by a display panel.

The present invention refers to environmental protection type intelligent current-reducing and energy-saving control equipment method for street lamp. It contains single lamp controller circuit and street lamp circuit, wherein single lamp controller circuit module consisting of LCU control circuit module and multiple tapping power reducing ballast module, the output of said LCU control circuit respectively connected with one end of multiple tapping power reducing ballast, ac compensation capacitor module and street lamp circuit module through one end of multiple step control equipment of 220 ac power supply. Said invention has advantages of realizing single lamp independent timing or networking control, street lamp soft startups control, and street lamp relative constant power control etc, without harmonic contamination to electric power network, and prolonging street lamp service life.

The invention relates to an automotive vehicle traffic security early-warning prevention controlling system, which aims at improving the security coefficient of a driver, reducing the traffic accidents, recording the traveling data of the automotive vehicle and the driver, and notifying the vehicle owner of the current state, the position range and the positioning function in time. Through a real-time three dimensional video frequency image and a sonar system to identify the obstacles at the front and rear sides, the emergency lamp signals, the brake lamp signals, and the traffic light signals to identify the a highway street sign mark to limit a highest vehicle travel speed. If the driver takes no emergency measure during the early-warning process, the system automatically adopts the corresponding vehicle speed reduction, engine closing and emergency braking. The correlative traveling state date of the automotive vehicle is stored for 30 days uninterruptedly. Through the system software to process the sonar and video frequency image date, the overspeed fatigue driving of the driver, the alcohol content detection, jumping the red light, and the stealing prevention and the go astern anti-collision early warning of the automotive vehicle are checked all whether. The automotive vehicle speed, the driver state and the data of the live images at the front and rear sides of the automotive vehicle are recorded.

The invention discloses a visible light communication system based on TCP / IP. The system comprises a transmitter and a receiver. The transmitter comprises a digital transmission unit, a light transmission unit and a light transmission module, wherein the digital transmission unit, the light transmission unit and the light transmission module are connected in turn. The receiver comprises a light receiving module, a light receiving unit and a digital receiving unit, wherein the light receiving module, the light receiving unit and the digital receiving unit are connected in turn. The system and the method, which are provided by the invention, have the advantages of high transmission power, spectrum applying preventing, electromagnetic interference preventing, safety, confidentiality and high available bandwidth, and are capable of realizing high bandwidth and high rate wireless communication access at low cost.

The invention relates to a single-chamber dual-vibrator piezoelectrical pump, belonging to the mechanical field of micro-electronic fluid. A pump body is fixedly connected between an upper cover and a lower cover; an inlet pipe and an outlet pipe are respectively and fixedly connected with the water inlet and a water outlet of the pump body; the front part of a pump chamber is fixedly connected with a pump chamber driving piezoelectrical vibrator 1; the water inlet of the pump chamber is fixedly connected with a check driven valve 1 or a drive valve 1; the invention is characterized in that the rear of the pump chamber is fixedly connected with a pump chamber piezoelectrical vibrator 2; the water outlet of the pump chamber is fixedly connected with a check driven valve 2 or a drive valve 2. The invention has the advantage that as the piezoelectrical vibrator has the advantages of fast responding, no electromagnetic interference, etc., the two drive vibrators in the pump chamber are led to keep harmonious and consistent, thus increasing the output flux and improving the output performance of the piezoelectrical pump.

The invention discloses a mobile phone Android camera positioning system based on LED visible light communication and a positioning method thereof. The positioning system includes an LED visible light communication module, a signal receiving module, and a mobile phone positioning software module. The LED visible light communication module includes LED lamps. The mobile phone visible light communication signal receiving module includes a developed visible light communication camera. The visible light communication camera includes single camera heads on a mobile phone, and a camera system. The mobile phone positioning software module includes mobile phone client APP software which runs under an Android system and contains a positioning algorithm. An indoor positioning APP is loaded from a mobile phone client, and then, images can be taken using the camera system directly. Corresponding modulation information of each LED lamp is acquired by scanning the flick of the LED lamp, and the location of each lamp is determined through decoding. The exact location of the mobile phone client is calculated through the positioning algorithm, and the result is displayed on the mobile phone APP. Therefore, indoor positioning is realized.

The invention relates to a pneumatic ball kicking system of a football robot, comprising a ball horizontally pushing kicking foot, a cylinder output rod, a cylinder, air pipe interfaces, a stand, a connecting rod, a ball lifting kicking foot, a ball lifting kicking foot board, a rotary pushing head and a motor. A pneumatic control loop comprises a cylinder output rod, a cylinder, a two-position five-way electromagnetic valve, a two-position three-way electromagnetic valve and an air storage bottle. The ball kicking system can realize switching between ground ball and air ball by changing the angle of the rotary pushing head. The force of kicking the ball can be regulated by changing duration of electrifying the two-position five-way electromagnetic valve, namely changing the flux of air flowing into the right cavity of the cylinder. The invention realizes a pneumatic ball kicking system which can regulate force of kicking the ball, and can play ground ball and air ball. The invention has simple structure and easy realization, and can greatly improve the competition ability of the football robot, particularly ball kicking ability.

The invention relates to a vehicle self-organization network for LED communication and belongs to the technical field of automobiles. The vehicle self-organization network consists of nodes containing vehicle-mounted LED communication units, wherein the nodes comprise a vehicle terminal node and a mobile relay node; the vehicle terminal node communicates with the mobile relay node in the self-organization network by virtue of the vehicle-mounted LED communication units; the mobile relay node communicates with mobile relay nodes in other self-organization networks by virtue of the vehicle-mounted LED communication units; and the vehicle self-organization network also comprises a fixed access point, the vehicle terminal node can communicate with the fixed access point by virtue of the LED communication units, and all the LED communication units in the network perform communication by adopting a phase shift MIMO-OFDM (Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing) LED communication system. The vehicle self-organization network for LED communication, provided by the invention, ensures that each vehicle is in a 'car in the net' state, and has a function of resisting a multipath effect and intersymbol interference, so that the LED communication among vehicles is realized reliably.

The invention relates to a monitoring and controlling system based on optical communication. The monitoring and controlling system comprises a sensor, a central control unit, an optical signal transmission unit and a terminal control unit, wherein the sensor is used for detecting measurand and transmitting corresponding information of the measurand to the central control unit; the central control unit is used for transmitting a control instruction to the optical signal transmission unit according to the information of the measurand; the optical signal transmission unit is used for transmitting out the control instruction in a form of an optical signal; the terminal control unit is used for receiving the optical signal and controlling terminal equipment according to the optical signal. According to the monitoring and controlling system based on optical communication disclosed by the invention, the detection control on the measurand is realized, so that a spectrum resource does not need to be applied for, no electromagnetic interferences exists, and the resource utilization efficiency can be improved. The monitoring and controlling system can be used for monitoring and controlling the measurand such as temperatures, humidity, illumination intensity, pH (Potential of Hydrogen) values, pressure, flows, liquid levels, differential pressure and ultrasonic waves.

The invention relates to a device and a method for measuring the rotating speed of a rotating shaft based on a variable density sine fringe. The device comprises the variable density sine fringe, a high-speed image collection module, a high-speed image transmission module, an imaging processing software module and a computer. The method comprises the following steps: adhering a sensor for the variable density sine fringe onto the surface of the periphery of a rotating shaft to be measured; carrying out continuous imaging and recording on the variable density fringe by the high-speed imaging collection module; transmitting an image of the fringe to the computer by the image transmission module; carrying out Fourier transform on fringe signals at the positions of the same row of pixels in each frame of image by the image processing software module and adopting a peak frequency correction method to accurately correct peak frequency so as to obtain accurate fringe density information, then obtaining a time domain curve with which a rotation angular speed of the rotating shaft at the position of the fringe is covered, and then calculating the rotating speed signal of the rotating shaft through the rotation angular speed and the sampling frequency of a camera. According to the device and the method, non-contact measurement for the rotating speed of the rotating shaft in a certain range of rotating speed can be realized, and the device is high in measuring speed and high in precision.

The invention relates to a lens module which comprises a lens barrel, a flexible circuit board, an image sensor and an electromagnetic shielding case, wherein the lens barrel is provided with a first accommodating cavity and a second accommodating cavity communicated with the first accommodating cavity; at least one optical lens is accommodated in the first accommodating cavity; a glass cover board is accommodated in the second accommodating cavity; the flexible circuit board is adhered to the surface of the glass cover board, which is far away from the first accommodating cavity; at least one end of the flexible circuit board extends out of the lens barrel from the inside of the lens barrel; a through opening is formed on the flexible circuit board; a plurality of bonding pads and a plurality of zero potential junctions are formed on the surface of the flexible circuit board, which is far away from the glass cover board; the image sensor comprises a photosensitive region and a signal region; the photosensitive region is over against the opening; the signal region is provided with second bonding pads corresponding to the first bonding pads; the second bonding pads are electrically connected with the first bonding pads; the electromagnetic shielding case is provided with an accommodating groove for accommodating the image sensor, is attached to the flexible circuit board and is grounded through the zero potential junctions. The invention also provides a portable electronic device using the lens module.

The invention relates to a built-in charging management type battery pack and particularly relates to a charger, a battery management system and a storage battery pack. The battery pack is mainly composed of a casing, a charging module, a management module and a battery pack body, wherein the charging module, the management module and the battery pack body are arranged inside the casing. The battery pack is characterized in that the built-in charging management type battery pack is designed specially, and module integration and functional optimization are achieved at the aspects of electronic devices, circuits (control circuits, voltage stabilizing circuits and detecting circuits), electromagnetic compatibility and heat management, so that the battery pack has the advantages of being small in size, light in weight, free from electromagnetic interference, stable in electrical performance, safe and the like, charging and management functions are integrated and built inside battery casings, batteries can be charged conveniently and quickly, the charger is not required to be carried with users, and the battery pack is low in charging energy consumption, high in efficiency, safe and reliable.

The invention discloses a crossing toll collection device based on visible light communication. The device comprises a visible light communication device, a controller, a snapshot device and a computer, wherein the visible light communication device is used for achieving data communication between vehicles and a toll station; the controller is used for controlling a lane handrail and a signal lamp; the snapshot device is used for taking candid photographs of the vehicles; the computer is connected with the visible light communication device, the controller and the snapshot device. The invention further discloses a toll collection system of the crossing toll collection device based on visible light communication. The toll collection system comprises a plurality of crossing toll collection devices based on visible light communication, the computers of the crossing toll collection devices based on visible light communication are connected with a switch of the toll station, and the switch is connected with a toll-station server and a database of an expressway system. Ground induction coils do not need to be buried in advance, the visible light communication technology is combined, headlamps of the current vehicles are used fully, erroneous judgment of the vehicles is avoided, and the number of communication dead zones is reduced.

The invention discloses a high-voltage switch cabinet wireless temperature measuring system which comprises a temperature monitoring and early warning workstation, a temperature measuring communication terminal and a plurality of wireless temperature sensors. The temperature monitoring and early warning workstation comprises a management computer and a database. The management computer is connected with the temperature measuring communication terminal through the Ethernet, the wireless temperature sensors and the temperature measuring communication terminal are packaged in a grounding type shielding mode so that anti-electromagnetic interference can be achieved, the 915.00MHz operation frequency based on ISM is applied to wireless data connection so that hurt to the human body and electromagnetic interference in surrounding devices can be avoided, the problem that at the high-voltage, large-current, strong-electromagnetic-interference and high-sealing states, a common sensor can change the creep distance of an electrical device can be effectively solved, the purposes that a high-voltage electrical device is accurately detected online in real time and especially the problem that the hidden danger of overheating exists in each connector position is solved can be effectively achieved, and therefore the application prospect is good.

The invention aims to provide a single axle air bearing table balancing adjustment method with simple principle, low cost and convenient operation. The balancing adjustment method includes the following steps: step 1: the single axle air bearing table is adjusted to be not horizontal and a gradienter is used to measure an angle Alpha between the plane of the air bearing table and the local horizontal line; step 2: the air bearing table is caused to sway to-and-fro under the action of gravity and the swaying amplitude and cycle are recorded; step 3: the actual eccentricity L of the gravity and a revolving center of the single axle air bearing table are calculated according to the swaying cycle; step 4: a corresponding balance weight is arranged on a central line of recorded swaying angles at two sides of the air bearing table to adjust the balance; and step 5: the above steps are repeated until the eccentricity is zero or small enough to meet engineering requirements. The balancing adjustment method has simple principle, convenience, practicability, low cost and no electromagnetic interference to the single axle air bearing table.

The invention provides a test table used for studying friction vibration energy recycling efficiency. In a motor module, a hollow support base is fixed on a machine base in a movable manner, a servo motor is mounted in the hollow support base and a brake disc is fixed on the upper portion of a motor output shaft. In a loading module, two support boards are fixed on the machine base in a movable manner; a hydraulic cylinder is mounted on a top board above the two support boards; a hydraulic cylinder guide rod protrudes from a linear bearing downwards; a normal force sensor, a tangential force sensor and a brake block are connected to the guide rod in sequence; piezoelectric elements are fixed on spring steel sheets on three side faces of the brake block while a three-dimensional acceleration sensor is fixed on the last side face. According to the invention, brake loading pressure, brake disc rotation speed, friction diameter and the like are changed according to practical working conditions and influence on friction vibration energy recycling efficiency by different working conditions is studied through verifying piezoelectric type friction vibration energy collection feasibility through electric signals collected in tests.

The invention discloses an optical fiber cantilever beam magnetic field sensing probe based on a giant magnetostrictive film, and belongs to the technical field of optical fiber sensors. The optical fiber cantilever beam magnetic field sensing probe comprises an optical fiber, a fixing and supporting end, an optical fiber cantilever beam, a chromium metal film and the giant magnetostrictive film. The optical fiber cantilever beam is arranged on the optical fiber end surface. The optical fiber cantilever beam is connected with the optical fiber end surface through the fixing and supporting end. The optical fiber cantilever beam and the optical fiber end surface form a Fabry-Perot resonant cavity. The chromium metal film and the giant magnetostrictive film are plated on the external surface of the optical fiber cantilever beam in turn. In a magnetic field to be measured, telescoping of the giant magnetostrictive film results in the deflection of the optical fiber cantilever beam or the change of the resonant frequency, and the deflection of the optical fiber cantilever beam or the change of the resonant frequency is detected by the Fabry-Perot resonant cavity so as to measure the size of the external magnetic field.

The invention discloses an intelligent electric vehicle V2V communication system based on LED visible light communication. The system comprises a visible light transmitting unit and a visible light receiving unit, wherein the visible light transmitting unit converts some electrical signals generated in a VCU into optical signals by using high-speed modulated visible light emitted by a vehicle-mounted LED as an information carrier, and transmitting the optical signals to free space; the optical light receiving unit uses a transparent glass type solar panel to detect the visible light, receives an optical carrier signal, decodes to acquire vehicle information and sends the information to the VCU. Compared with the prior art, the system provided by the invention builds communication between the vehicles by sending and receiving the optical signals, and is simple in operate, free of electromagnetic interference and high in reliability. Meanwhile, the system provided by the invention adopts the transparent glass type solar panel to serve as a collection device of the optical signals, and integrates the effects of being transparent, shielding wind, charging and collecting signals, so that arrangement of hardware is greatly reduced, and hardware cost and energy are saved.

The invention discloses a temperature self-compensating fiber grating micro force sensor and a manufacturing method thereof. The sensor comprises a force-bearing end cover, a sensor upper shell, a sensor lower shell, a hard core, a supporting cylinder and a round elastic diaphragm, wherein the hard core comprises a hard core screw and a hard core nut; the top part of the supporting cylinder passes through the sensor upper shell, and the bottom part is fixed with the hard core screw; the supporting cylinder is internally provided with a fiber, a first fiber grating and a second fiber grating are carved on the fiber, one end of the first fiber grating is fixedly connected with the top part of the upper shell and the other end is fixed with the hard core screw and is in a tensioning state, and one end of the second fiber grating is connected with the lower part of the hard core screw and the other end passes through the sensor lower shell and is in a free elastic state. The structure is simple; the force measurement sensitivity and the force measurement range of the sensor can be changed in a large range, production and manufacturing of batch sensors with multiple specifications are facilitated; temperature self compensating can be realized; and long-term and reliable effective monitoring by the sensor in a temperature-varying environment can be realized.

The invention discloses a vehicle-mounted air condition air sweeping device driven by an electric control shape memory alloy. The vehicle-mounted air condition air sweeping device is composed of a drive part, a control part, a transmission part and an execution mechanism. The drive part adopts the shape memory alloy as a drive element, the shape memory alloy shrinks when electrified to be heated and is lengthened when cooled, and output of displacement and force of a driver is achieved. The control part is composed of a sensor, a single-chip microcomputer and a manual control key, the current on a shape memory alloy wire is controlled, and therefore the temperature of the shape memory alloy wire is controlled. The transmission part is mainly composed of a clutch device or a reset device. The execution mechanism is vehicle-mounted air conditioner air sweeping blades. The vehicle-mounted air condition air sweeping device has the beneficial effects of being small in size, simple in structure, convenient to install, easy to achieve, free of electromagnetic interference, good in periodical control effect and the like.

The invention relates to a hydrodynamic force catapulting device of a carrier-borne aircraft and relates to the technical field of weapon launching. The medium state and energy conversion processes from seawater to fresh water and then from fresh water to high-pressure steam are not need for achieving the catapulting device, and a seawater medium in the ocean is directly used for transmitting energy and acting, so that the device is simple in structure, compact in size, low in energy consumption in the catapulting process and high in energy use rate. In addition, the catapulting device uses high-pressure seawater as catapulting power, no electromagnetic interference is generated, and invisibility of a naval ship and reliable and stable work of mechanical and electrical equipment on the naval ship are facilitated.

The embodiment of the invention provides a digital radio electronic system for toll collection of roads and parking lots. The system comprises a first radio transmission device which is arranged at a toll collection monitoring point and is used for transmitting and looking up a message required by an electronic license plate; a first radio receiving device which is arranged in an vehicle entering or exiting a toll station and is used for receiving and decoding a first radio signal; a second radio transmission device which is arranged the vehicle entering or exiting a toll station and is used for transmitting a second radio code signal including information of the electronic license plate; a second radio receiving device which is arranged at the toll collection monitoring point and is used for receiving and decoding a second radio signal; a monitoring point processor which is used for controlling, coding and decoding signals from the monitoring point; a vehicular processor which is used for controlling, coding and decoding signals of vehicles entering or exiting the toll station; an electronic license plate unit which is used for storing information of an electronic license plate identification code; and a toll charging unit which charges according to vehicle classes and the entering and exiting time thereof. The system has the advantages of being reliable, environmental protection, 24-hour service, being easy to be realized, convenience in integration with an ITS system and the like.

The invention relates to a static-pressure direct drive rotating table which comprises a base seat and a rotating plate, wherein the rotating plate is assembled on the base seat in a rolling mode through a static-pressure bearing, and the axial line of the rotating plate extends along an up-and-down direction. The static-pressure bearing is arranged in the middle part of the rotating plate. At least one circle of static-pressure bearing guide rail pair is arranged in the periphery of the static-pressure bearing between the base seat and the rotating plate. The static-pressure direct drive rotating table is small in processing amount of the rotating plate and large in axial bearing capacity.

The under-voltage protection method includes the following steps: inputting the cell voltage as power source voltage to the voltage comparator; comparing the power source voltage with one preset reference voltage in the voltage comparator; and cutting off the power supply loop from the cell in case the power source voltage is lower than the preset reference voltage, or else returning back to the comparing step. The present invention also provides one under-voltage protector, which includes under-voltage protecting circuit and cell on-off controlling circuit. The present invention can realize the under-voltage protection of cell simply and reliably at low cost and without need of software control and data communication, electromagnetic interference and environment dependence.

The invention discloses a high-temperature resistant FBG (fiber bragg grating) sheet type strain sensor and a manufacturing method thereof. The strain sensor consists of an FBG, a polyimide film, an armored cable and an optical fiber connector, wherein the FBG is connected with the polyimide film; the armored cable is connected with the FBG; the optical fiber connector is connected with the armored cable; and when the strain of a structural component is monitored, the surface of the monitored object needs to be milled by abrasive paper, and the polyimide and FBG composite sheet is stuck on the monitored object with adhesives. The method adopts a polyimide curing technology and comprises the following steps of: sealing the FBG and polyimide into a mould, and organically combining through heating, curing and cooling to form a polyimide and FBG composite sheet; leading out the armored cable from the end part of the polyimide and FBG composite sheet; and sticking the polyimide and FBG composite sheet on the surface of the structural component to be monitored by use of high-temperature resistant adhesives. The strain sensor disclosed by the invention resists high temperature, has good durability and high measurement accuracy, and is in quasi-distributed arrangement, free from electromagnetic interference and convenient to construct.