CN109363302A - A kind of tamper bracelet and tamper detection method - Google Patents
A kind of tamper bracelet and tamper detection method Download PDFInfo
- Publication number
- CN109363302A CN109363302A CN201811275618.3A CN201811275618A CN109363302A CN 109363302 A CN109363302 A CN 109363302A CN 201811275618 A CN201811275618 A CN 201811275618A CN 109363302 A CN109363302 A CN 109363302A
- Authority
- CN
- China
- Prior art keywords
- circuit
- microcontroller
- wrist strap
- tamper
- receiving
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
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Classifications
-
- A—HUMAN NECESSITIES
- A44—HABERDASHERY; JEWELLERY
- A44C—PERSONAL ADORNMENTS, e.g. JEWELLERY; COINS
- A44C5/00—Bracelets; Wrist-watch straps; Fastenings for bracelets or wrist-watch straps
- A44C5/0007—Bracelets specially adapted for other functions or with means for attaching other articles
-
- A—HUMAN NECESSITIES
- A44—HABERDASHERY; JEWELLERY
- A44C—PERSONAL ADORNMENTS, e.g. JEWELLERY; COINS
- A44C5/00—Bracelets; Wrist-watch straps; Fastenings for bracelets or wrist-watch straps
- A44C5/02—Link constructions
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B21/00—Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for
- G08B21/02—Alarms for ensuring the safety of persons
- G08B21/0202—Child monitoring systems using a transmitter-receiver system carried by the parent and the child
- G08B21/0286—Tampering or removal detection of the child unit from child or article
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- Health & Medical Sciences (AREA)
- Child & Adolescent Psychology (AREA)
- General Health & Medical Sciences (AREA)
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring And Recording Apparatus For Diagnosis (AREA)
Abstract
The invention discloses a kind of tamper bracelet and tamper detection methods.Tamper bracelet includes center housing, the first wrist strap, the second wrist strap and warning circuit, first wrist strap and the second wrist strap are connect with center housing respectively, warning circuit includes microcontroller, transmit circuit, receives circuit and alarm module, and alarm module, transmit circuit and reception circuit are connect with microcontroller respectively；Transmit circuit includes transmitting coil, and receiving circuit includes receiving coil, and transmitting coil is embedded in the first wrist strap, and receiving coil is embedded in the second wrist strap, and when the first wrist strap and the second wrist strap fasten, receiving coil receives the signal that transmitting coil emits by near-field coupling.Tamper bracelet of the invention is realized that two wrist straps are close and separation detection, is solved the drawbacks of prior art contact electrically detects, testing result is accurate and reliable, is not easy to report by mistake by the way of wireless coupling.
Description
[technical field]
The present invention relates to electronics bracelet more particularly to a kind of tamper bracelet and tamper detection methods.
[background technique]
The electronics bracelet of integrated positioning or RFID has preferable application effect in the management domain of special population, such as supervises
The applications such as prison, hospital, home for destitute.It is function indispensable in such applications that the tamper of electronics bracelet and wrist strap, which remove alarm,
?.
Application No. is a kind of intelligent tamper bracelet of the disclosure of the invention of CN201711110389.5, including it is warning circuit, anti-
Water center shell, the second wrist strap, the eye-splice seat for being connected to the first wrist strap end, is connected to inserting for the second wrist strap end at the first wrist strap
Discount, warning circuit include the first alarm circuit being embedded in the first wrist strap, the second alarming line being embedded in the second wrist strap
Road, the controllable signal an alert being arranged in waterproof center shell warning circuit plate, be provided with metal connection in eye-splice seat
Needle is embedded with metal connection hole in eye-splice head, and after eye-splice head is inserted into eye-splice seat, the metal connection needle in eye-splice seat is inserted into eye-splice
Metal connection hole in head, the first alarm circuit, metal connection needle, metal connection hole, the second alarm circuit and warning circuit plate
Closed circuit is formed after being sequentially connected.For the intelligence tamper bracelet after putting on for the first time, any one place on intelligent tamper bracelet is disconnected
Fall, the dismantling-proof alarming circuit board that can be triggered in intelligent tamper bracelet issues alarm signal.
The invention by eye-splice head, will be embedded in the alarm circuit in the alarm circuit and the second wrist strap of the first wrist strap and
Circuit board connects into a closed circuit.The production technology of this structure is complicated, needs inbuilt alarm circuit in two wrist straps
Between have an electrical connection, and the metal contact device for needing to be electrically connected is exposed in jack.Metal contacts device may be because with the passing of time
Oxidation or abrasion, lead to poor contact and warning circuit are caused to report by mistake.
[summary of the invention]
The technical problem to be solved in the present invention is to provide a kind of testing result is accurate and reliable, it is not easy the tamper bracelet reported by mistake.
Another technical problems to be solved of the invention are to provide a kind of tamper detection method set up and state tamper bracelet.
In order to solve the above-mentioned technical problem, the technical solution adopted by the present invention is that, a kind of tamper bracelet, including center shell
Body, the first wrist strap, the second wrist strap and warning circuit, the first wrist strap and the second wrist strap are connect with center housing respectively, warning circuit
Including microcontroller, transmit circuit, receive circuit and alarm module, alarm module, transmit circuit and receive circuit respectively with it is micro-
Controller connection；Transmit circuit includes transmitting coil, and receiving circuit includes receiving coil, and transmitting coil is embedded in the first wrist strap
In, receiving coil is embedded in the second wrist strap, and when the first wrist strap and the second wrist strap fasten, receiving coil is received by near-field coupling
The signal of transmitting coil transmitting.
Above-described tamper bracelet, transmit circuit include driving circuit and transmitting match circuit, and receiving circuit includes connecing
Receive match circuit and detector amplifier；Microcontroller, transmitting match circuit, receives match circuit, detection amplification at driving circuit
On circuit boards, circuit board layout is in center housing for circuit and alarm module arrangement.
Above-described tamper bracelet, including the first flexible circuit board and the second flexible circuit board, transmitting coil are etched in
On first flexible circuit board, receiving coil is etched on the second flexible circuit board；First flexible circuit board is moulded in the of plastic cement
In one wrist strap, the second flexible circuit board is moulded in the second wrist strap of plastic cement；The connector of first flexible circuit board and the second flexibility
The connector of circuit board respectively with circuit board electrical connection.
Above-described tamper bracelet, driving circuit include amplifier, transmitting match circuit include first capacitor and second
Capacitor, first capacitor, the second capacitor and transmitting coil constitute transmitting LC resonance circuit；The input termination microcontroller of amplifier
Carrier pulse signal output end；Emit the output end of the input termination amplifier of LC resonance circuit.
Above-described tamper bracelet, receiving match circuit includes third capacitor and capacitance, third capacitor and reception
Coil, which is constituted, receives LC resonance circuit；Detector amplifier includes diode and triode, and the anode of diode passes through blocking electricity
Hold the output end for receiving LC resonance circuit, the cathode of diode connects the base stage of triode, and the collector of triode passes through resistance
Connect DC power supply, emitter ground connection；The collector of triode connects the voltage sampling signal input terminal of microcontroller.
A kind of tamper detection method of above-mentioned tamper bracelet, detection process the following steps are included:
601) microcontroller emits continuous pulse to transmit circuit；
602) microcontroller persistently detects the voltage for receiving circuit output, when receiving the electric voltage exception of circuit output, then
Determine that tamper bracelet is unlocked；
603) microcontroller is alarmed by alarm module.
Above-described tamper detection method, detection process the following steps are included:
701) microcontroller is spaced is detected incessantly according to set time；
702) in step 601, the PWM controller outgoing carrier signal of microcontroller；
703) in step 602, the input voltage V1 of microcontroller detection ADC；The PWM controller of microcontroller is stopped
Only outgoing carrier signal, microcontroller detect the input voltage V2 of ADC again；Microcontroller compares input voltage V1 and input electricity
Press V2；If the difference between input voltage V1 and input voltage V2 is less than set threshold value, then determine that tamper bracelet has solved
It opens；
704) circuit will send the result of judgement microcontroller by wireless communication in step 603.
Tamper bracelet of the invention realizes that two wrist straps are close and separation detection, solution are existing by the way of wireless coupling
There is the drawbacks of technology contact electrically detects, testing result is accurate and reliable, is not easy to report by mistake.
[Detailed description of the invention]
The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.
Fig. 1 is the structural schematic diagram of tamper bracelet of the embodiment of the present invention.
Fig. 2 is the block diagram of tamper bracelet warning circuit of the embodiment of the present invention.
Fig. 3 is the circuit diagram of tamper bracelet transmitting and receiving circuit of embodiment of the present invention coupling.
Fig. 4 is the wiring diagram of microcontroller of the embodiment of the present invention.
[specific embodiment]
The structure of tamper bracelet of the embodiment of the present invention is as shown in Figures 1 to 4, including waterproof center housing 1, the first wrist strap 2,
Second wrist strap 3 and warning circuit.
First wrist strap 2 and the second wrist strap 3 are connect with waterproof center housing 1 respectively, and warning circuit includes microcontroller
(MCU), transmit circuit, reception circuit and alarm module.Alarm module, transmit circuit and reception circuit connect with microcontroller respectively
It connects.
Transmit circuit includes driving circuit, transmitting match circuit and transmitting coil 201, and receiving circuit includes receiving matching electricity
Road, detector amplifier and receiving coil 301.
Microcontroller, transmitting match circuit, receives match circuit, detector amplifier and alarm module cloth at driving circuit
It sets in PCB circuit board 4, printed circuit board 4 is mounted in waterproof center housing 1.
Transmitting coil 201 is etched on the first flexible circuit board (FPC), and receiving coil 301 is etched in the second flexible circuit
On plate (FPC).First flexible circuit board is moulded in the first wrist strap 2 of silica gel, and the second flexible circuit board is moulded in the of silica gel
In two wrist straps 3.The connector of the connector of first flexible circuit board and the second flexible circuit board is respectively welded on printed circuit board 4,
It is electrically connected with the circuit on printed circuit board 4.
When tamper bracelet is worn on hand, the first wrist strap 2 and the second wrist strap 3 are fastened, receiving coil 301 and transmitting coil
201 partially overlap, and receiving coil 301 receives the signal that transmitting coil 201 emits by near-field coupling.When tamper bracelet is taken off
When, two coil separation, receiving coil 301, which cannot be coupled to, receives the signal that transmitting coil 201 emits
As shown in Fig. 2, driving circuit include amplifier U1-A, transmitting match circuit include capacitor C1 and capacitor C2, capacitor
The second end of C1 connects the first end of transmitting coil L1, the second end ground connection of transmitting coil L1, and capacitor C2 and transmitting coil L1 simultaneously connects.
Capacitor C1, capacitor C2 and transmitting coil L1 constitute transmitting LC resonance circuit.The input terminal PULSE of amplifier U1-A connects
The carrier pulse signal output end PULSE of microcontroller.Input termination of the first end of capacitor C1 as transmitting LC resonance circuit
The output end of amplifier U1-A.
Receiving match circuit includes capacitor C3 and capacitance C6, capacitor C3 and receiving coil L2 and to meet composition reception LC humorous
Shake circuit.Detector amplifier includes diode D1 and triode T1, and the anode of diode D1 is received by capacitance C6
The output end of LC resonance circuit, the i.e. first end of receiving coil L2, the second end ground connection of receiving coil L2.
The cathode of diode D1 connects the base stage of triode T1, and the collector of triode T1 connects DC power supply by resistance R3,
Emitter ground connection.Resistance R2 connects between the collector and base stage of triode T1, and resistance R1 connects the base stage and ground in triode T1
Between, the collector of triode T1 connects the voltage sampling signal of microcontroller as the output end RECEIVE of detector amplifier
Input terminal RECEIVE.
MCU has the ASK pulse of modulated signal by I/O port transmitting, is input to driving circuit, and driving circuit realizes power
Amplification, is then linked into transmit circuit.
Receiving coil and match circuit receive signal by way of near-field coupling, from transmitting coil, are amplified by detection
After circuit, it is input to the ADC detection foot of MCU.
Driving circuit is used to the I/O port output signal of MCU carrying out power amplification, if the I/O port of MCU has stronger drive
Kinetic force can then save driving circuit.Transmitting coil and transmitting match circuit constitute a LC resonance circuit, resonance frequency
The carrier pulse that rate and MCU are emitted is identical.MCU emits carrier pulse can be realized using PWM or timer.
Receiving coil and reception match circuit constitute a LC resonance circuit, the resonance frequency phase of resonance frequency and transmitting terminal
Together.Detector amplifier, including detection and signal amplify two functions.Detection is by the way of envelope detection, detecting signal packet
Amplify after network through amplifying circuit.
MCU and driving circuit, transmitting match circuit, reception match circuit and detector amplifier are all laid in bracelet
On the circuit board in portion, transmitting coil and receiving coil are then embedded in respectively on two wrist straps of bracelet.When bracelet is worn, two
Wrist strap partially overlaps, and receiving coil can be coupled to the signal of transmitting coil.When bracelet is taken off, receiving coil is far from emission lines
Circle, cannot be coupled to the signal of transmitting coil.If any one side of wrist strap is cut, receiving coil equally can not receive transmitting coil
Signal.
MCU detects whether wrist strap is worn at a certain time interval.When detection, control I/O port sends out one section of carrier pulse, carries
Wave impulse refers to the square-wave signal of a bit of specific frequency, and the input signal of ADC is detected in transmitting；Then stop hair carrier wave arteries and veins
Punching, then detect the input signal of ADC.If ADC sampled value when sending out carrier wave and ADC sampled value when not sending out carrier wave have obviously
Gap, then illustrate that two wrist straps partially overlap, i.e. wearing state., whereas if the ADC of two states samples value difference
Away from unobvious, then illustrate that two wrist strap standoff distances are larger, that is, take off state.The ADC sampled value has apparent gap, is
It is realized by one threshold value of setting, threshold value is measured by testing.
In the present embodiment, MCU uses nRF52832.MCU has the ASK arteries and veins of modulated signal by I/O port P0.06 transmitting
Punching, is input to driving circuit U1-A, and the model of U1-A is 74LVC2G04, realizes power amplification.Signal input after power amplification
To the LC resonance circuit being made of capacitor C1, C2 and transmitting coil L1.
The ASK pulse carrier frequency of the present embodiment is 16MHz, is generated by the PWM of nRF52832.Capacitor C1, C2 and coil
L1 is matched to the resonance frequency of 16MHz.
Receiving coil L2 and capacitor C3 forms received LC resonance circuit, and resonance frequency is also 16MHz.Capacitor C6 is blocking
Capacitor, enters diode D1 by the signal of C6 and carries out envelope detection, carries out low level signal amplification subsequently into triode T1.Three poles
The collector output signal of pipe T1 is linked into the ADC input pin P0.02 of MCU.
The detection process of tamper bracelet of the embodiment of the present invention sequentially includes the following steps:
1) microcontroller carries out wearing detection by once per second incessantly.
2) carrier signal of the PWM controller output 16M of microcontroller, emits continuous pulse to transmit circuit.
3) after output is stablized, microcontroller persistently detects the voltage for receiving circuit output, when the voltage for receiving circuit output
When abnormal, then determine that tamper bracelet is unlocked:
Wherein, microcontroller first detects the input voltage V1 of ADC, and the ADC input voltage V1 of detection is the flat of multiple repairing weld
Mean value.
4) PWM controller of microcontroller stops outgoing carrier signal, and microcontroller detects the input electricity of ADC again
Press V2.
5) microcontroller compares input voltage V1 and input voltage V2.Such as the difference between input voltage V1 and input voltage V2
Value is less than set threshold value, then determines that tamper bracelet has been unlocked.
Set threshold value is obtained by the empirical value of experiment.
6) by judging result, circuit is sent microcontroller by wireless communication.
The tamper bracelet of the embodiment of the present invention realizes that two wrist straps are close and separation detection by the way of wireless coupling,
The drawbacks of prior art contact electrically detects is solved, testing result is accurate and reliable, is not easy to report by mistake.
Claims (7)
1. a kind of tamper bracelet, including center housing, the first wrist strap, the second wrist strap and warning circuit, the first wrist strap and the second wrist
Band is connect with center housing respectively, which is characterized in that warning circuit includes microcontroller, transmit circuit, receives circuit and alarm
Module, alarm module, transmit circuit and reception circuit are connect with microcontroller respectively；Transmit circuit includes transmitting coil, is received
Circuit includes receiving coil, and transmitting coil is embedded in the first wrist strap, and receiving coil is embedded in the second wrist strap, the first wrist strap with
When second wrist strap fastens, receiving coil receives the signal that transmitting coil emits by near-field coupling.
2. tamper bracelet according to claim 1, which is characterized in that transmit circuit includes driving circuit and transmitting matching electricity
Road, receiving circuit includes receiving match circuit and detector amplifier；Microcontroller, transmitting match circuit, receives driving circuit
On circuit boards, circuit board layout is in center housing for match circuit, detector amplifier and alarm module arrangement.
3. tamper bracelet according to claim 2, which is characterized in that including the first flexible circuit board and the second flexible circuit
Plate, transmitting coil are etched on the first flexible circuit board, and receiving coil is etched on the second flexible circuit board；First flexible circuit
Plate is moulded in the first wrist strap of plastic cement, and the second flexible circuit board is moulded in the second wrist strap of plastic cement；First flexible circuit board
Connector and the second flexible circuit board connector respectively with circuit board electrical connection.
4. tamper bracelet according to claim 2, which is characterized in that driving circuit includes amplifier, transmitting match circuit
Including first capacitor and the second capacitor, first capacitor, the second capacitor and transmitting coil constitute transmitting LC resonance circuit；Amplifier
The carrier pulse signal output end of input termination microcontroller；Emit the output end of the input termination amplifier of LC resonance circuit.
5. tamper bracelet according to claim 2, which is characterized in that receiving match circuit includes third capacitor and blocking electricity
Hold, third capacitor and receiving coil constitute and receive LC resonance circuit；Detector amplifier includes diode and triode, diode
Anode the output end of LC resonance circuit is received by capacitance, the cathode of diode connects the base stage of triode, triode
Collector DC power supply is connect by resistance, emitter ground connection；The collector of triode connects the voltage sampling signal of microcontroller
Input terminal.
6. a kind of tamper detection method of tamper bracelet described in claim 1, which is characterized in that detection process includes following step
It is rapid:
601) microcontroller emits continuous pulse to transmit circuit；
602) microcontroller persistently detects the voltage for receiving circuit output, when receiving the electric voltage exception of circuit output, then determines
Tamper bracelet is unlocked；
603) microcontroller is alarmed by alarm module.
7. tamper detection method according to claim 6, which is characterized in that detection process the following steps are included:
701) microcontroller is spaced is detected incessantly according to set time；
702) in step 601, the PWM controller outgoing carrier signal of microcontroller；
703) in step 602, the input voltage V1 of microcontroller detection ADC；The PWM controller of microcontroller stops defeated
Carrier signal out, microcontroller detect the input voltage V2 of ADC again；Microcontroller compares input voltage V1 and input voltage
V2；If the difference between input voltage V1 and input voltage V2 is less than set threshold value, then determine that tamper bracelet has been unlocked；
704) circuit sends the result of judgement to microcontroller by wireless communication in step 603.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811275618.3A CN109363302A (en) | 2018-10-30 | 2018-10-30 | A kind of tamper bracelet and tamper detection method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811275618.3A CN109363302A (en) | 2018-10-30 | 2018-10-30 | A kind of tamper bracelet and tamper detection method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109363302A true CN109363302A (en) | 2019-02-22 |
Family
ID=65390410
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811275618.3A Pending CN109363302A (en) | 2018-10-30 | 2018-10-30 | A kind of tamper bracelet and tamper detection method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109363302A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110288804A (en) * | 2019-07-26 | 2019-09-27 | 清研讯科（北京）科技有限公司 | A kind of wearable device, monitoring method and monitoring and alarming system |
| CN111830432A (en) * | 2019-03-26 | 2020-10-27 | 比亚迪股份有限公司 | Anti-dismantling animal monitoring device and anti-dismantling method thereof |
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| US6144303A (en) * | 1999-02-01 | 2000-11-07 | Exi Wireless Systems, Inc. | Tag and system for patient safety monitoring |
| CN103794022A (en) * | 2012-11-02 | 2014-05-14 | 北京计算机技术及应用研究所 | Wearing-type anti-dismantling alarm apparatus |
| CN104821059A (en) * | 2015-04-20 | 2015-08-05 | 青岛歌尔声学科技有限公司 | Anti-picking detection system and anti-picking detection method for wrist strap type electronic product |
| CN106723714A (en) * | 2017-01-23 | 2017-05-31 | 深圳市雅美时塑胶电子有限公司 | Intelligent tamper bracelet |
| CN107822271A (en) * | 2017-11-12 | 2018-03-23 | 泉州市拓迪派克电子有限公司 | A kind of intelligent tamper bracelet |
| CN209528088U (en) * | 2018-10-30 | 2019-10-25 | 深圳市华士精成科技有限公司 | A kind of tamper bracelet |
-
2018
- 2018-10-30 CN CN201811275618.3A patent/CN109363302A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6144303A (en) * | 1999-02-01 | 2000-11-07 | Exi Wireless Systems, Inc. | Tag and system for patient safety monitoring |
| CN103794022A (en) * | 2012-11-02 | 2014-05-14 | 北京计算机技术及应用研究所 | Wearing-type anti-dismantling alarm apparatus |
| CN104821059A (en) * | 2015-04-20 | 2015-08-05 | 青岛歌尔声学科技有限公司 | Anti-picking detection system and anti-picking detection method for wrist strap type electronic product |
| CN106723714A (en) * | 2017-01-23 | 2017-05-31 | 深圳市雅美时塑胶电子有限公司 | Intelligent tamper bracelet |
| CN107822271A (en) * | 2017-11-12 | 2018-03-23 | 泉州市拓迪派克电子有限公司 | A kind of intelligent tamper bracelet |
| CN209528088U (en) * | 2018-10-30 | 2019-10-25 | 深圳市华士精成科技有限公司 | A kind of tamper bracelet |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111830432A (en) * | 2019-03-26 | 2020-10-27 | 比亚迪股份有限公司 | Anti-dismantling animal monitoring device and anti-dismantling method thereof |
| CN110288804A (en) * | 2019-07-26 | 2019-09-27 | 清研讯科（北京）科技有限公司 | A kind of wearable device, monitoring method and monitoring and alarming system |
| CN110288804B (en) * | 2019-07-26 | 2021-10-26 | 清研讯科（北京）科技有限公司 | Wearable device, monitoring method and monitoring alarm system |
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