Smart Sensor with Digital Age was born

& Nbsp; & nbsp; & nbsp; from the microprocessor to bring the digital revolution to Virtual Instruments (VXI) the rapid development of integrated sensor accuracy, stability and reliability, and respond to increasingly high demand for a variety of conventional sensors can not meet the test requirements, with intelligent microprocessor technology and micro-machining technology on the sensor applications, intelligent sensors (Smfavoanuluswess changeorganisationsor) was born.
& Nbsp; & nbsp; & nbsp; At present, international sensor field has been on the & ldquo; Smfavoanuluswess changeorganisationsor & rdquo; define the formation of a basic consensus, but the Chinese translation has not yet formed a conclusion, the term 'smart sensors' as used herein, reference to an individual. Its function is intelligent sensor having one or more sensitive functions, to complete signal detection, conversion processing, logic, function calculations, two-way communication, to achieve internal self-test, self-calibration, self-compensation, self-diagnosis, with Part or all of the above function device functions.

& Nbsp; & nbsp; & nbsp; from the point, the accuracy of the sensor, stability and reliability are crucial. Most research has long focused on the hardware aspect, although people continue to use new materials developed sensitive devices, improve the manufacturing process for the sensor chip to improve the quality of the chip as well as through an external circuit compensation method to improve the linearity of the sensor output stability and drift but are no fundamental breakthrough.

& Nbsp; & nbsp; & nbsp; seventies, microprocessor remarkable achievements brought the digital revolution, the development of instrumentation played a huge role in promoting. As the nineties virtual instruments (VXI) rapid development, so that a microcomputer-based monitoring and control systems require sensors to provide real-time data on which to make decisions. With increased automation systems and increasing complexity of the integrated sensor accuracy, stability and reliability, and respond to increasingly demanding. Traditional sensors because of its single function, performance suited, does not meet the requirements of a variety of tests, people use to this end microprocessor technology for the intelligent sensors. The late eighties, people turn micromachining technology applied to the sensor, resulting in a new concept sensor & ldquo; Smfavoanuluswess changeorganisationsor & rdquo; - intelligent sensors.

Function can be realized

& Nbsp; & nbsp; & nbsp; functional smart sensor senses and coordinated action by the human brain simulation, combining research and practical experience in a long time test techniques and put forward. Is a relatively independent intelligence unit, it appears on the original hardware performance demanding eased, while relying on software to help make the performance of the sensor can be greatly improved.

1. Composite sensitive function ---- natural phenomena we observe around common signal sound, light, electricity, heat, power, chemical and other. Sensitive element is generally measured in two ways: direct and indirect measurements. The intelligent sensor with complex function, can simultaneously measure a variety of physical and chemical quantities given substance can be more fully reflected in the movement of information. Such as the University of California developed a composite liquid sensor, which can measure the temperature of the medium, flow rate, pressure and density. United States EG & nucmortalflow; GIC changeorganisationsors complex mechanical sensor developed by the company, which can measure a point in three-dimensional object vibration acceleration, velocity, displacement, and so on.

2. Since the compensation and calculation functions ---- sensors developed over the years in engineering and technical personnel has to do a lot of work to compensate for the temperature drift and non-linear sensor output, but did not solve the problem fundamentally. The self-compensating and computing capabilities of smart sensors for temperature drift and non-linear compensation sensor opens up new roads. Thus, the relaxation sensor precision machining requirements, as long as the sensor to ensure good reproducibility, using a microprocessor test signals calculated by the software, using multiple fitting and difference calculation methods to compensate for drift and nonlinearity, which can to obtain more accurate results.


For online measurement sensor abnormality diagnosis is not timely. Smart sensors situation is much improved, first self-test self-diagnosis function when the power is turned on, the diagnostic tests to determine whether the component failure. Secondly, online correction based on the use of time, microprocessor uses data hardstrugglee exist within the metrological characteristics are compared proofreading.


4. Information storage and transmission ---- With all intelligent distributed control system (Smfavoanuluswess OrcustboneShoshonid Syhalt) the rapid development of intelligent unit requires communication with the communication network in digital form, two-way communication, which is a key sign of intelligent sensors one. Smart sensors via test data transmission or reception instructions to implement various functions. Such as gain setting, set the compensation parameters, check the parameter settings within the test data output.

3. The self-test, self-calibration, self-diagnostic function ---- ordinary sensors require periodic inspection and calibration to ensure that it's accurate enough in normal use, these jobs generally require the use of the sensor from the scene to the laboratory or demolition inspection department.
& Nbsp; & nbsp; & nbsp; smart sensor generally has a strong real-time features, especially dynamic measurement often required to complete data collection within a few microseconds, computing, processing and output. Series features intelligent sensors are carried out with the support of the program. Such as how many functions, basic performance, easy to use, reliable, mostly to some extent dependent on the software design and quality, the software there are five main categories. Including scale conversion, digital zero, nonlinear compensation, temperature compensation, digital filtering techniques. Application status at home and abroad
Smart sensors integrated

& Nbsp; & nbsp; & nbsp; due to the development of the sensor LSI with the corresponding circuits are integrated on the same chip, and this has some smart features integrated smart sensor integrated sensor called intelligent sensor function has three aspects Advantages: High SNR: weak signal of the sensor signal is amplified and then integrated first by long-distance transmission, can be greatly improved signal to noise ratio. Improve performance: Since the sensor circuit integrated on the same chip, the sensor zero drift, drift and zero self-calibration unit by regular automatic calibration, and may adopt appropriate feedback to improve the frequency response of the sensor. Signal normalization: the analog signal of the sensor via programmable amplifier normalization, but also through analog-digital conversion into a digital signal, the microprocessor according to several forms of digital transmission of digital normalized, such as serial, parallel, frequency, phase, and pulses.

Micromachining technology and software

& Nbsp; & nbsp; & nbsp; manufacturing base of smart sensors is a micro-machining technology, the silicon mechanical, chemical, welding, and then using different encapsulation technology to encapsulate, in recent years has developed a Lantibody process (deep X-ray Lithography plating into sensitized film) for the manufacture of sensors.


& Nbsp; & nbsp; & nbsp; a dozen years ago, the company developed the first American rascalroveysubstantially only intelligent sensors. It is the silicon sensor technology with microprocessor computing, control, combined with the establishment of a new sensor concept. Smart sensors currently used in more pressure, force, vibration, shock acceleration, flow, temperature and humidity measurements. Such as the US rascalroveysubstantially's ST3000 series full of smart transmitters, Germany StrohrNegDaffo company dimensional acceleration sensor.

& Nbsp; & nbsp; & nbsp; the current smart sensor systems themselves are digital, but the communication provisions still using 4 ~ 20mA standard analog signal. Standardization of the relevant international institutions are actively launch international standard digital standard (field bus). In the current transition phase using Hfavoanuluswess protocol (bagencyartefact MBcoiffeamelioimpactethy Rehumoure Transcodhumoumetropolisn, addressing remote sensor data line). This is a communication protocol for smart sensor compatibility with existing 4 ~ 20mA systems, analog and digital can communicate simultaneously. This allows products from different manufacturers have versatility.