Mesuirng engineering study
I am currently studying for the more accurate recognition of the face of a person. Accepts information through sensors and digitizes this information to facilitate copying, gathering, and editing or information. In order t o understand the concpet of control, it is necessary to understand the sensor and the actuator. Collecting data through the sensor, and using the information to drive the actuator. The actuator and the physical dynamic system are called the plant. The controller is called a controller. A summary of the breif terms is needed for exam.
1. Control System
Plant: System to be controlled
Inputs: Commands, driving signals, or excitations
Outputs: Resposes of the system
Sensors: Devices that measure system variables
Acuators: Devices that drive various parts of the system
Controller: Device that generates control signal
Control law: Relation or scheme acrroding to which the control signal is genereated
Control system: As least the plant and the controller
Feedback contrl: Control signal is determined according to plant response
Open-loop control: Plant response is not used to determine the control action
Feedforward control: Control signal is determined according to plant excitation or a model of the plant
Most analog signals require some form or preparation before they can be digitzed. Signal conditioning is the manipulation of a signal in a way that prepares it for the next stage of processing.
Ultimately, the important thing is to make analog information digital. Research is underway to minimize the loss of information as much as possible. The following terms are used to describe the static characteristics of a measurement system.
Accuracy is the perofrmance of a measuring instrument that indicates how much error is betwwen measured and actual values. Precision is the performance of a measuring instrument that indicates the degree of dispersion between measured values. Linearity must satisfy two qualities. Additivity and homogeneity of degree 1. These two features are called superposition principles. Monochemistry is the porperty of preserving a given order.
The terminology for dynamic properties is as follows
I need to presents the basic form of the 0th order system, the 1st, the 2nd order system
They have characteristic, time variable, RC, RL circuits, enery s torage and dissipate.
Finally, depending on the position of the pole, I can see whether the values converge or oscillate.
2. ADC
Analog to Digital Converter
ADC means to convert an analog signal into a digital signal. Digital signals are represented using discrete numerical values with specific minimum units of information. The advantage is less information loss due to external disturbance or noise. Digital information is easy to process data sucah as duplication, deletion, and editing, and there is little difference from t he original information.
The vertical d ivision of a signal is called resolution, and the horizontal division is called quantization. The sampling rate referes to the number of measurements per second. The higher the smapling rate, the closer to the original. According to the Nyquist Shannon smapling theorem, band-limited continuous signals can be completely reconstructed by sampling at more than twice the maxumum frequency of the signal. The conversion of digital information into analog information is c alled modulation. In the opposite case, it is called demodulation.
3. Encoder
An encoder is a device that measures the direction, speed, and angle of rotation. Ecoders consist of a n object with regularly spaced holes, a sensor that emits light from one side of the object and receives light. The principle is that as soon as the object turns, one sensor emits light and the other receivers a pulse signal. I can measure the direction and angle by interpreting the received signal. The concpet of multiplication is to use one counter as four conters by using the image of two channels. This gives a finer resolution.
Here, the concpet of the resolution is d escribed more in d etail. If the data has 8-bit resolution, it means that the d ata is divided into 2^8. The larger the number of bits, the more specific the data can be obtained.
4. Calibration and Curve fitting
Calibration means that the instrument is readjusted to the scale of the unit of measurement. Coding takes error of actual value and measured value. Cftool, curve fitting is a major feature of matlab. It is to make a mathematical modeling through several pieces of data. At this time, in the column for selecting the function type, the model with the smallest RMSE is selected. RMSE is the root means square error. The mathematical formula is as follows. This is the most basic content or regression analysis. SSR and SSE mean the values excluding the average value and route, SST is defined as being the sum, over all observations. of the squared difference of each observation from the overall mean, and R^2 meas SSR/SST.