TWI234935B - Encoding method of high-resolution magnet inductive encoder - Google Patents

Abstract

The present invention relates to an encoding method of high-resolution magnet inductive encoder, in which first and second sine/cosine waveform signals with a phase difference of 90 degrees are commonly divided into 16 intervals form 0 to 360 degrees, each interval having 22.5 degrees. The encoding method cascades the first and second sine/cosine waveform signals via two inverting amplifiers, respectively, and loads an impedance matching. Based on determining the condition that the edge angles of the two sine waveform signals at the equally divided intervals of 22.5 degrees have a constant ratio, it is able to resolve more useful output signals. Then, these added output signals are combined with the comparator and the logic circuit for output. In addition, it is also applicable to use the analog to digital converter in a microprocessor to equally divide the sine waveform signal outputted from the magnetic encoder of a motor. This method allows the overall frequency multiplying technique to be established on a programmable basis, thereby possessing the advantage of modifying the program. Finally, a comparison circuit is employed to utilize the rising edges and falling edges of the two kinds of signals to achieve the effects of high frequency multiplication and high resolution.

Description

1234935

[Technical field to which the invention belongs] The present invention relates to a two-finger encoding method of a high-resolution magnetic sensor encoder, which employs stylized technology to achieve easy maintenance and is `` flexible '', which can be multiplied by the system's requirements. There is no need to modify the body, and the hardware is modified so as to reach those who can significantly reduce the manufacturing cost and improve the competitiveness of the product industry. [Previous technology] s Press, in general, the traditional magnetic sensor senses the signal from the encoder 疋 two sine waves with a phase difference of 90 degrees, the waveform is shown in the first figure, one of which is a sine wave ( sinewaveform), and the other is a cosine waveform. The encoding processing method of these two sine waves with a phase difference of 90 degrees is to use the zero-crossing point for cutting. Therefore, the signal generated after cutting ^) is as shown in the lower figure of the first figure Due to the tradition, the Λ number cutting method simply converts the sensed signal into a digital signal, which does not increase the resolution. However, many precision electronic devices today have a tendency to perform high speeds and high precision in the execution speed, and the structure Λ α is ten or more times. Therefore, the aforementioned traditional coding technology cannot achieve precision Demand for electronic equipment. The second figure shows the basic architecture of an A / D converter (ADC). In the process of A / D change, it basically passes through the pre-filter, then samples the analog signal, quantizes (quantizing) 'coding', and transforms it into a digital value. . As for the general encoding technology to improve the resolution by the ADC, there will be many problems. The speed will be different, and the faster the speed, the higher the speed.

Page ‘especially’ because the magnetic sensor senses that the encoder ’s sine wave amplitude will follow the motor 1234935

It will be smaller, so it is difficult to increase the resolution with the general ADC method, which is hardly feasible. Known technology about high-resolution encoders has been disclosed in the U.S. Patent Gazette and invented by Santos et al. The patent name is "High resolution encoder" and the patent numbers are 4,987,41 5 and 5, 0 8 9, 8 1 7 and other two patents, but they belong to the design of fixed institutions, do not have the function of flexible selection of frequency multiplication, the industrial scope of use is limited. [Summary of the invention] Therefore, the main purpose of the present invention is to provide a high-resolution magnetic sensing encoder encoding method, and use programmatic technology to achieve convenient maintenance and flexible frequency doubling. According to the system requirements, the frequency value only needs to modify the program without modifying the hardware circuit to achieve a significant reduction in manufacturing costs and improve the competitiveness of the product industry. In order to achieve the above object, the present invention distinguishes two first sine wave δK and first sine wave signal waveforms with phase difference g 0 degrees from 0 degrees to 3 6 0 degrees into 16 sections with a width of 22 5 degree interval. The encoding method is ^ The two sine wave signals are connected in series through two inverting amplifiers, and equipped with impedance matching. Based on these two sine wave signals, the boundary angle is fixed at the 22.5 degree equal interval. The condition of the ratio is judged to parse out more available output signals; 嗣, then these increased output signals are combined with the comparator and the logic circuit to set the output, and the comparison circuit is used to use the rising and falling edges of the two signals. ^ To high-resolution (such as sixteen-fold) high-resolution effects. In addition, the encoding method of the above two sine wave signals can also use an analog digital converter (ADC) in the microprocessor to divide the sine wave signal output by the magnetic encoder used by the motor into equal parts. Alas, according to these two strings, Wave 1 at 22 5 1234935

The condition that the boundary angle of the equal interval interval has a fixed ratio is judged, and the comparison circuit is used to use the rising and falling edges of these two signals to achieve a high-resolution effect; this method can make the overall frequency multiplication technology based on a stylized basis. ^ 上 'has the advantage of convenient program modification. [Embodiment] The present invention can implement a high-resolution encoder by using an operational amplifier (〇perati〇nal Ampl if ier (hereinafter referred to as 〇PA)) hardware circuit and a microprocessor. The preferred implementation examples are described in detail below: An operational amplifier (Operational Amplifier, hereinafter referred to as 0PA) hardware circuit is used to implement a high-resolution encoder: Basically, the present invention ^ This preferred embodiment of the magnetic sensor is an encoding method of the encoder. The signal of $ is also Two sine wave signals that are 90 degrees out of phase (as shown in the third picture), so one of the two sine waves can be regarded as the first sine wave signal, such as a sine wave (sine wavef0rm), and the other as A second sine wave signal, such as a cosine waveform. Firstly, in order to implement a high-resolution encoder, a preferred embodiment of the present invention presents the relationship between these two sine wave signals with a phase difference of 90 degrees as a 16-division motion at 360 degrees shown in the fourth figure; Among them, the horizontal axis (that is, the sense axis) represents the sine signal (sin0), and the vertical axis (that is, the gamma axis) represents the system and cosine signal (cos 0), so that it can be divided into 16 sections with a width of 22 · 5. The interval of degrees, as shown in the fifth figure is the interval boundary diagram. Due to the sine signal of the x axis) and the cosine signal of the y axis (c0s0) at 22 5 degrees, sinlcoW has a value of 0.414 times. Relationship, therefore, using this relationship and some other basic theorems of sine waves, you can use this as a personal deduction when you are in the mountain K rrr — ^ ^

Ml 1234935

Case No. 93104877 V. Description of the Invention (4) The opposite relationship is called, such as the qi, second and fourth signals of the signal A (Channe 1 A), the sum of the signal B (Channe 1 B), The second formula and the fourth formula, so this phase can be used v two one formula and the first circuit 'from the formula to see that the signal A requires eight comparators, but Lee', to simplify the symmetric inverse relationship and the gate and anti-OR gate The relationship of input inversion, i this formula reduces eight comparators to four comparators, the two in the formula can change ^ and the four you n will become two and the gate two anti-or gate, the ninth In the figure, the first, w, and gate are (> = 1 followed by a circled square) whose output is equal to the inverse OR gate formula [(X > 0) & (y > x)], the ninth graph The second formula is the third formula of the first sixth figure, the third formula of the ninth figure is the reverse OR gate compound, the two formulas are equal to the fourth formula of the sixth figure, and the fourth formula of the ninth figure is the sum gate. ^ The output is equal to the second expression, and finally used in the place where the four expressions are output-one: the square without the circle in the back of the sixth figure) is combined into a single = Q (> = 1 output line, signal B Also with Analogy. Therefore, using this and what you want, you can further get the multiplier diagram shown in Figure 7. The figure also shows that the design method of the hardware part above is to use an operational amplifier (OPA) for signal magnification. The change and the signal are compared with each other to reach / cut. In the magnification change part, the operational amplifier (〇ΡΑ) is used for two or two suppressions. 'Just adjust the ratio of the resistor to do different magnification conversions.' Make the required signal. ', Through the interval boundary diagram shown in the "five figures", it can be clearly understood that the required signals are six signals such as X, -X, 0.414X, Υ, -Υ, and 0.414γ. In the preferred embodiment, as long as the above two original signals (ie, the sine signal and the cosine signal) are connected in series through two inverting amplifiers 0P1, 0ρ2 and 0ρ3, and 0ρ4, they can be matched with appropriate impedance matching. Produce the signals needed above

Page 8 1234935 (Amendment No. 93104877-Y and 0.414Y), the schematic diagram of the circuit is as shown in V. Description of the invention (5)

(X, -X, 0.4414X, Y are shown in the eighth figure. Then these signals are compared with each other according to the relationship in the fifth figure, and the comparison circuit is included, including: comparators CPI, CP2, CP3, CP4, CP5 , CP6, CP7, CP8, and combined with the logic circuits of their respective needs (please refer to Figure 9), LI, L2, L3, L4, L5, L6, L7, and L8 can each obtain four pulse waves PI, After the outputs of P2, P3, P4, ρ5, P6, P7, and P8 ', the signals of P1, P2, P3, and? 4 can be combined with the gates and the signals of P5, P6, P7, and P8 can be combined with the gates. ^ In order to get the final logic circuit output L9 and L1 0, which is the output signal we want Output Α and Output Β (this signal has four times the frequency). This method is doing lower frequency doubling technology (such as four times the frequency ), Because the hardware circuit is less complicated and the signal processing speed is fast, the hardware system processing system is a more suitable choice. However, if you want to handle higher frequency multiplication technology, the system integration and system expansion will be caused by the expansion of the hardware circuit. Difficult to debug, in addition, because the use of 〇pA for proportional division in resistance value matching needs A certain degree of accuracy, otherwise it is very easy to cause output errors, which has certain difficulties in practical application. Firstly, in order to achieve a higher frequency doubling technology, the present invention can improve the SP'1. Another preferred embodiment is to use a microprocessor (such as a 1 Λ analog digital converter (channel) to convert the magnetic coding analog digital conversion of the motor 'and continuously calculate the latest conversion line to divide each group of sine waves in intervals. Signal arrival: using this method can make the overall frequency multiplication technology in the process, only need to modify the number in the program ..., need to modify the hardware circuit 'λ greatly increase the system bomb 1234935 _ case number 93104877 V. Description of the invention (6) The target of cost. Furthermore, in another preferred embodiment of the present invention, the internal signal of the microprocessor, DC can be used to convert the sine wave signal into a digital value for the nose, and then divide it in equal proportions. The judgment method calculates the value corresponding to the sine wave segmentation point. Finally, when = i = equal to the expected response, this is not the case; ^ is better than simplifying the system and easy to maintain. As an implementation tool, The frequency multiplier is selected. The upper phase t has impeached silver. In actual testing, the MSP-430 6-frequency multiplication technology can be completed in the microprocessor. The tenth figure shows another preferred implementation of the present invention = the entire 16-frequency multiplier. The block diagram of the circuit can be divided into two parts BL0CK1 and 虬 0 (: 1 (2; where the first half (ie BL0cn) is the part described earlier, and the signals Ph a and Ph B are equal to the first Figure 9 compares the electrical output signal A (0utput A) and the output signal B (〇utput B). The ^ part is to count the rising / falling edges of the Ph A and Ph B signals. There are four pulse waves. If you take a sine wave, there will be eight pulse waves in the Ph A plus Ph B signal in j time, and one pulse wave will have a rising edge and a falling edge. The whole count will have 6 The number of collars counts up or down to determine whether the signal A " also leads A, in this way you can achieve 16 times the effect. Please refer to the waveform diagrams shown in the examples of the present invention after actual testing. Please refer to the following two: :: 不 'Four sets of signals can be found in the figure, which are two sets of sine waves and square waves. The A, B, 丄, and mouth of the encoder output are input to the ADC channel of the MSP-430. When the program starts, the ADC will dare; 1 ¾ r r ice but lacks m 〇 sample period 5 w time interval for these two groups The sine wave signal undergoes A / D conversion, π-_, --- and the latest conversion value is continuously substituted into the mathematical module V.LIMUP..IJ ... .............. ....... Sun page 10

1234935 Amend case number 93104877 V. Description of the invention (7) Perform operations to divide each group of chords by interval; and because there are two signals A and 6, so = will: Four square wave signals are achieved to achieve 16 times the frequency Resolution.彳 A total of eight square waves can be cut to achieve the above. According to the above description, we can know the coding use of the device. For example, the application number X can be applied to various electronic devices with high resolution. You can use two types of signals to raise and lower the edge of the signal. ^ The feedback to the director is raised to 800. The Lima motor is used in extremely accurate positioning * 1 200 'or higher. If you use Tailuming ^ system, there will be better control, so that the modification and maintenance are also very simple, there are significant applications, and I kindly ask for your help; d ::: ding 'love to file a patent for invention according to law is not worth mentioning, only It is only the preferred feasible embodiment of the present invention, and the enclosing: two: the limit, the scope of implementation of the present invention 'for all changes and modifications equivalent to the invention patent ^ ^ should still belong to the yoke encompassed by the invention patent Inside, hereby declare it. Page 11 1234935-± _3__ 倏 正 __ as shown in the first picture, > The original signal from the encoder after being edited by i / crying magnetic sensor Wave chart. "# The basic structure of the general ADC converter is shown in Figure 2. The second figure is a schematic diagram of the original signal from the encoder and the output of the encoder through the magnetic sensor according to the embodiment of the present invention. The fourth diagram is a schematic diagram of two sine waves with a phase difference of 90 degrees and 16 equal divisions at 360 degrees in the embodiment of the present invention. The fifth figure shows the boundary map of the 22.5 degree interval in the fourth figure. The sixth diagram is the interval diagram relative to the rotation in the fourth diagram. The seventh figure shows the output of the quadruple frequency in the embodiment of the present invention. The eighth figure is a schematic diagram of the impedance matching of the fourth frequency in the embodiment of the present invention. The ninth figure is a schematic diagram of the signal ratio of the quadruple frequency in the embodiment of the present invention. The tenth figure is a block diagram of a 16-frequency multiplication circuit according to the embodiment of the present invention. The eleventh figure is a waveform diagram when the 16-fold frequency of the embodiment 16 of the present invention is tested.

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Claims (1)

1234935 ———__ y No. 93104877 __correction___ VI. Patent application scope 1 · A high-resolution magnetic sensing encoder encoding method, which is a first sine wave signal with two phase differences of 90 degrees With the second sine wave signal, it is divided into 16 sections with a width of 2 2 · 5 degrees from 0 to 36 °. This coding method passes the two sine wave signals through two inverting amplifiers each. It is connected in series and equipped with impedance matching. According to the condition that the two sine wave signals have a fixed ratio in the boundary angle of the 2 2 · 5 degree equal interval, it can analyze more available output signals, and then increase these additional wheels. The output signal is combined with the comparator and the logic circuit 5 to output again, and combined with the comparison circuit, the rising and falling edges of the two signals are used to achieve the effect of high frequency and high resolution. 2 · —An encoding method of a high-resolution magnetic sensor encoder, which divides two first sine wave signals and second sine wave signals with a phase difference of 90 degrees into 16 sections from 0 to 36 The width is 22.5 degrees. The encoding method uses an analog digital converter (ADC) in the microprocessor to divide the sine wave signal output by the magnetic encoder used by the motor into equal parts. According to the two sine waves above The δK 5 tiger judges the condition that the boundary angle of the 2 2 · 5 degree netting interval has a fixed ratio, and uses a comparison circuit to use the rising and falling edges of these two signals to achieve the high-frequency effect of the south frequency. 3. The encoding method of the high-resolution magnetic sensor encoder according to item 1 or 2 of the scope of patent application, wherein the first sine wave signal is a sine signal (si η 0). The encoding method of the high-resolution magnetic sensor encoder according to the first or second range of the range, wherein the second sine wave signal is a cosine signal (cos Θ). Page 13