Nowhere is absent rate can say in this word life in us, we understand the working principle that quickens sensor today, so that we are better the electronic equipment in use life.

 

Quicken a kind of equipment that sensor just as its name implies can measure a product acceleration one kind namely. We are general and commonly used in the life basically is two kinds of accelerometer, it is angular acceleration respectively plan with the line accelerometer. We divide it again in the life fasten for 4 sort, it is sensor of type of sensor of sensor of acceleration of the type that suppress report, acceleration of the type that control block, capacitance type sensor, servo respectively.

 

 

Acceleration sensor has two kinds: One kind is angular acceleration sensor, it is snail appearance improves You Tuo come over. Another kind is line acceleration sensor. It also can be pressed measure an axis to divide the axis that it is sheet, double axis and sensor of 3 axes acceleration.

 

The specific application domain of acceleration sensor basically is in automobile safety domain, sport control domain, image retroflexions automatically domain, electron compass tilts the compensation domain of blind angle of navigation system of corrective domain, GPS, pedometer function domain, prevent a hand to shake functional domain, Shan Xingong can domain, hard disk protects a domain, nowhere is not in involved wide it may be said, this shows, we know the value of the working principle that quickens sensor.
 

 

Our common most sensor is basically general principle of a job, that is piezoelectric effect. We make the introduction to piezoelectric effect incidentally, so that let the everybody’s better job principle that understands it. Piezoelectric effect shows certain dielectric is in namely encounter outside influence and metabolic moment, can produce polarization in crystal interior this kind of phenomenon, can arise in the surface of crystal at the same time the charge of negative pole. When outside influence disappears, can return not electrified initiative condition again, this is piezoelectric effect. We are told below tell a few when acceleration sensor applies common domains.

 

 

Acceleration sensor already was applied extensively at car electron domain, main concentration is held in automobile body accuse, safe system and navigation, typical application if automobile safety gasbag (Airbag) , ABS is prevented hold dead brake system, electron in the arms to stabilize a program (ESP) , electronic-controlled and pensile system.

 

Automobile body is at present safe more and more the attention that gets people, the amount of safe gasbag in the car is increasing, the requirement that answers sensor is stricter and stricter also. System of whole gasbag control includes the concussion sensor outside automobile body (Satellite Sensor) , install park door, roof, the acceleration sensor of the position such as the backlash before mixing (G-Sensor) , electronic controller, and safe gasbag. Electronic controller is 16 normally or 32 MCU, when automobile body is bumped, concussion sensor can send signal inside a few small seconds to this electron controller.

 

Subsequently controller meets the electron reach seat according to amount of the intensity of collision, passenger instantly / the parameter such as the position of safety belt, the data that cooperates to distributing to be passed in the sensor of whole railroad car undertakes calculate and be makinged be assessmented accordingly, explode through report inside the shortest time driver (Squib Driver) the life that starts safe gasbag to assure a passenger is safe.

 

Rely on ABS and traction control system to cannot satisfy car to be in only normally the safety of drive a vehicle that curves a section of a highway to go up asks. Stability of the electron below this circumstance controls a system (ESC) in can be being operated through amending a driver turn to inadequacy or oversteer, will control car to make its impartiality leaves way. This system measures the yaw angle of car through using a gyroscope, at the same time with sensor of low gravitational acceleration measures transverse acceleration. Measure income data and the result that through travelling speed and wheel banking angle two data computation gets to undertake comparing is opposite, adjust car to change direction to produce sideslip in order to prevent thereby.

 

Besides system of automobile body security beyond this kind of fundamental application, at present acceleration sensor is in in navigation system also acting important role. Its are main benefit realizes fixed position at GPS satellite signal. And in should entering satellitic signal to receive bad section or environment, if satisfy path, high-rise bristly, jungly region, because break,can write to date and lose navigation function. The sensor of 3 axes acceleration that is based on MEMS technology cooperates gyroscope or the component such as electronic compass can establish position together computative system (DR, dead Reckoning) , realize complementary sex application to GPS system.

 

 

 

As can apparel the development of intelligent equipment, especially medical treatment can apparel intelligent equipment, what basically rely on is sensor of all sorts of MEMS gyroscope that miniature changes, acceleration apply, with will detect the body of the person that apparel each information. For example, the MEMS sensor application in detecting without the heart that achieve an embryo.

 

Detect fetal heartbeat is technical very strong job, because fetal heartbeat is very fast, it is between 160 take second place of minutely L20 ～ , those who use a convention is stethoscopic the supersonic much Pu Leyi that puts large action only even, measure very hard with artificial computation accurate. In addition, action of supersonic and oscillatory wave at fetal, although very can big to fetal generation adverse effect detects dose is very small, also belong to caustic explores a category, unwell use at the examination of regular, repeatability and family.

 

At this moment, MEMS acceleration sensor, can offer a kind to detect without the heart that achieve an embryo method, development goes a kind to learn easily simply, intuitionistic and accurate interpose at fetal heart stethoscopic with Duopule between fetal custody appearance clinical diagnose the medical treatment with pregnant woman self check to assist an instrument.

 

Through acceleration sensor will fetal heartbeat is changed into imitate voltage signal, the buy before classics magnifies used instrument amplifier realizes the enlarge that need a value. Undertake a series of filter wave signal intermediate are handled next, change imitate voltage signal into digital signal with A/D converter. Input sheet through keeping apart parts of an apparatus solely piece machine undertake analytic handling, final output handles a result.

 

 

Be opposite as a result of huge data at present the demand of memory respect, hard disk is applied extensively to camera of notebook computer, mobile phone, number with yuan of parts of an apparatus such as CD driver / in photographing the equipment such as machine of camera, portable DVD, PMP. Portable equipment uses the account of the circumstance as a result of its, accident of classics regular meeting declines or be collided, and build didymous interior yuan the huge impact of parts of an apparatus.

 

To make equipment and among them data avoids damage to hurt, more and more users are right of portable equipment fight concussion ability to raise a requirement.

 

Of general portable product decline height is 1.2~1.3 rice, its can be made an appointment with the wallop of 50KG when striking area of marble quality of a material, the parts of an apparatus that the high speed such as hard disk rotates appears very flimsy below this kind of concussion however.

 

If be in hard disk inside buy sensor of 3 axes acceleration, should decline when happening, the system can detect acceleration abrupt change, carry out corresponding ego to protect an operation, if shut the electron with aseismatic poor performance or rigid parts of an apparatus, let magnetic head restoration, in order to reduce the damage rate of hard disk.