Device for moving object control
专利摘要:
A numerical control device for such as machine tool operation, in which position and speed of movement of the tool or the workpiece is automatically effected in accordance with a preset program and certain recorded preselected information. The control provides for movement along a segment of the desired path generally in three phases: 1) acceleration to a predetermined maximum speed; 2) constant speed, and, 3) deceleration to zero speed. However, provision is also made for continuous movement along adjacent path segments through elimination of the third phase of the first segment. 公开号:SU722503A3 申请号:SU681270193 申请日:1968-09-18 公开日:1980-03-15 发明作者:Помелла Пьеро;Лауро Лючино 申请人:Оливетти Энд Ко. С.П.А. (Фирма); IPC主号:
专利说明:
The recording country, with the second input of the third switching logic element, the third input of the arithmetic unit is the second input of the interpolator, the output of the write register is connected to the second input of the second switching logic element, the output of the memory unit is the second output of the interpolator, the output of the reading register is It is the third output of the interpolator. The disadvantage of this device also consists in the relatively low accuracy of the trajectory. The aim of the invention is to increase the accuracy of working out the trajectory. For this, a device for controlling a moving object containing a programmable block, a digital-analog converter, an interpolator, the first and second outputs of which are connected respectively to the inputs of the digital-analog converter and the programming block, the first, second, third, and fourth inputs are interpolated and connected to the corresponding the outputs of the programming block, the interpolator containing the memory block, the write register, the shift register, the first, second and third switching logic elements, the arithmetic k, data converter to parallel form, the output of which is the first output; the interpolator and the interpolator control unit associated with the arithmetic unit; the first and second inputs of the interpolator control unit are connected to the outputs of the write and read registers, respectively; the third input of the interpolator control unit the torus is the first input of the interpolator, connected to the first input of the arithmetic unit and connected to the control inputs of the first, second and third switching logic elements, the outputs of which x are connected respectively to the input of the memory unit, to the input of the readout register and to the input of the information converter into parallel form; the fourth and fifth inputs of the interpolator control unit are respectively the third and fourth interpolator inputs; the second input of the arithmetic unit is connected to the register output the readout, the fifth and sixth inputs of the interpol TRR are connected to the input of the write register, the output of the arithmetic unit is connected to the input of the write register, with the second input of the third switching logic element a, the third input of the arithmetic unit is the second input of the interpolator, the output of the write register is connected to the second input of the second switching logic element, the output of the memory block is the second output of the interpolator, the output of the register of the coupling is the third output of the interpolator, the computing unit is additionally entered , the first, second and third inputs of which are connected to the corresponding outputs of the programming unit, the fourth input is connected to the second output of the interpolator, the fifth and sixth inputs of which are connected to Respectively with the first and second outputs of the computing unit; In addition, the computing unit of the device contains an arithmetic node, a local control node whose output is connected to the control input of the arithmetic node, an input and output registers, a first and second reception registers, whose inputs are connected to the control inputs of the input and output registers and the first input of the node local control is the first input of the computing unit, the second input of which is connected by the second input of the second reception register, and the third input is connected to the second input of the node, local control, t The input of which is connected to the output of the input register and to the input of the arithmetic node, the output of which is connected to the input of the output register and the fourth input of the local control node, the outputs of the receive register and the output register are the first and second outputs of the computing unit, the input of the input register is the fourth input computing unit; in addition, the arithmetic unit of the device contains a decisive element, the first and second comparison circuits, the equality output of the first comparison circuit is connected to the first input of the second comparison circuit, the output of the decision element is connected to the second input of the first comparison circuit, and the output of the second circuit Comparison is connected to the first input of the first comparison circuit, the second and third inputs of the second comparison circuit are the control inputs of the arithmetic node. The following is a description of a preferred embodiment of the invention. Fig. 1 shows an example of the path of the moving part of the machine controlled by the proposed device; in fig. 2-5 are speed charts compared to a movement graph for the moving part of the machine; in fig. 6 is a block diagram of the proposed device; Fig. 7 shows successive sections of the path traveled by the moving part; in fig. 8, 9 - the contents of the registers at two different stages of work; in fig. 10 is a more detailed block diagram of the device in which its various components are disclosed; Fig. 11 shows a detailed logic diagram of the control units for the operation of a moving object control device. The device controls the operation of the machine in which the moving part moves along one or several axes. For example, we will assume that it is possible to move a moving part along two axes (X, Y, or X and Z, or Y, Z), which is carried out by an instrument that changes position relative to the workpiece or, conversely, it may consist in moving the workpiece relative to tool. Suppose that the moving part performs movement along a continuous trajectory (located in the plane of the X and Y axes), which is approximated by a series of straight line segments, the points of discontinuity lie on an ideal continuous line and are points defined by the program. Therefore, the moving part of the machine moves along straight line segments between each pair of consecutive points (see Fig. 1). For each straight-line segment P1-P2, P2-P3 trajectory, it is enough to determine the coordinates of the end point, and the advance rate or feed rate can be determined at the beginning of the program and whenever their value changes, install an interpolator with a memory device. Therefore, the program consists of a series of blocks, each of which contains a sequence of data of the type 1X-1Y-K1Y-K2Y-K3Y-K4V-K5V-IX-SX-KIXK2X-K3X-K4X-KbX-K6X-K7X-lY-KlV-K2VK3V -K4V-KbV-lY-SY-KlY-K2Y-K3Y-K4YK5Y-K6Y-K7Y-CR, in which lY, IX, IY are address code combinations showing that information relates to velocity V, X axis and axis respectively: SX and SY are code combinations showing the algebraic signs of the X and Y coordinates of the end points of a linear trajectory segment, the code combinations KIV and K5V are five decimal digits of the number at speed V; code combinations from K1X to K7X and from K1Y to K7Y are seven decimal digits of the number that defines, respectively, the X and Y coordinates of the end point; CR, which is a code combination meaning the end of a block, causes the interpolator to start to replenish the data in this block. The code combination block related to the axial movement and the OR code pattern can be preceded by the code combination AU1 and AtTN to control the machine's auxiliary operations, such as changing the speed and direction of rotation of the cartridge, lubrication, automatic tool change, etc. . It should be noted that the seven code combinations from K1X to K7X and KlY to K7Y express the tenth values of the X and Y coordinates from one micron to ten, in order to satisfy the required accuracy and maximum displacements. The five code combinations K1V to KbV in turn reflect the velocity values. Therefore, the data entered into the interpolator as a program block contains only the maximum feed or speed values and the coordinates of the end point. Further information, necessary for linear interpolation of the trajectory of the moving part between the starting and ending points, is calculated by the interpolator. From a starting point, for example, P1 (X1, Y1), the driving part should accelerate along the straight-line segment of the trajectory until it reaches the maximum allowable feed or speed and then the fixed distance should move at a constant speed it must move with deceleration in order to reach the final point P2 (X2, Y2) with zero speed. This type of movement is shown in Fig. 2, where the coordinate along the X axis is the abscissa and the speed along this axis is shown as the ordinate. Preferably, the segments between the coordinates x1 and xa and between the coordinates and are traversed with constant acceleration and constant deceleration, respectively. For linearity of the path to be traveled, it is necessary that the ratio between the increments of two coordinates X and y obtained for the same time interval be always equal to the ratio of the distances (xj-x) and () between two end points (figure 1), i.e. dx. Xj-xt (Behind in which d and dy show increments of the x, y coordinates. Therefore, the instantaneous velocities along these axes, as well as the instantaneous accelerations along these axes, will also be in specified relationship to each other. In order to move along a linear trajectory between P1 and P2 with a feed rate or speed, Corresponding to the graph of Figure 2, it is necessary to perform a series of calculations, which are performed by an interpolating device, in accordance with the principles described below. The interpolator operates cyclically, with DT being the constant interpolation cycle time. The component of the movement along the X axis will be considered first. Suppose that Xj is the coordinate of the starting point P1 of the linear trajectory, Xj, is the coordinate of the ending point of P2; X is the p-coordinate of the point of the trajectory in which the moving part is in the instant T of the beginning of the nth interpolation cycle; D x p is the propagation given by x, -, during the (n-1) interpolation cycle (this increment, which will be referred to as a positional increment, approximately proportional to the instantaneous velocity along the X axis, since DT is constant) .; DxM is a constant set by the beginning of the interpolation cycle, indicating the maximum increment allowed for the x coordinate, i.e. m is the maximum speed allowed along the x axis. During the whole cycle, the interpolation of the path between X and x should be met with the linearity condition of the X-ray Xi-Xi. In addition, during the initial phase TI (Fig. 2) of constant acceleration, the interpolator work according to the following formulas Dx (n + l): Dxn + hx x (n + 1) xn f Dx (n + l). The latter determines what the x position should be (n + 1 of the moving part at the end of the n-th interpolation cycle based on the Xr position at the beginning of this cycle. The first of these formulas determines the basis of the positional increment used in the previous interpolation cycle what the position increment should be (speed Dx (nH) to use it in the present nth interpolation cycle. Since hx is a constant, it is clear that this way the segment x, -x trajectories with constant acceleration proportional to hx. In addition, in In the initial phase T, the following additional operations are necessary to determine the moments when the acceleration changes are located in the graph of Fig. 2..) xn 1l 20xhp40xp Pxn Xj -HnaRun. The first of these operations determines the distance xx-x, traveled from the beginning of Xi of this trajectory segment to the end (p-1) of the interpolation cycle; this is the work; the distance is obtained from the distance i Dxn, passed from the end (p-2) of the interpolation cycle to the positional increment Dxn which takes place in the (p-1) interpolation cycle. The following operation is defined The value of the imaginary distance Pn equals the previously mentioned distance S Dxn xn-x, increased by the last increment Dxn. The value of Rxn is equal to the remaining distance, which the moving part must still pass before reaching the end point. In addition, during the entire phase T of constant acceleration in each interpolation cycle, a check is made that the instantaneous speed does not exceed the maximum allowable speed DxM. Similar operations are performed in the interpolating device, relative to the Y axis. The initial constant acceleration phase T determines the end of the interpolation cycle in which the maximum speed for the X axis or dp of the Y axis is reached. More precisely, the phase T determines the end of that interpol cycle For the X axis or Y axis, the increments of Dxn or Dyn are larger than the maximum allowable increments of DxM or DyM. It should also be noted that the final increments of DxnM and DynM 1 "yugut exceed the maximum increment of DxM and DyM by an amount not larger than the minimum increments of Rx and hy, respectively, i.e. phase T ends when the maximum speed allowed for these axes is reached along the X axis or along the Y axis. At the end of phase Tj, the summation IDxn represents the total distance x., Which is traveled along the X axis from the end of the interpolation cycle, during which the maximum speed was reached either along the X axis or along the Y axis. Therefore, the distance Xd - Xj represents It is a path that you need to go dp in order to achieve with a constant, acceleration maximum speed. The magnitude RhpM of the imaginary distance Pph, corresponding to a spacing of Xdx, is increased, as shown, and is stored in the corresponding register from the end of phase T, and is stored there. The initial phase Tj of the constant acceleration is followed by the phase T of the Constant speed (Fig. 2), during which the moving part continues to move at a speed equal to DxnM for the X axis and DynM dp of the Y axis, which it reaches at the end of the phase T. during phase T, the interpolator performs the following operations: X (P4-1) xn + DxnM Rxn Rxn RhpM. in the first formula, positional increment in the next interpolation cycle is constant and equal to DxnM; thus, the speed becomes constant. The equality is used for checking in each interpolation cycle of the condition that the remaining distance Rxn to the end point x is less than the specified one stored in the register. The constant speed phase Tj ends after this condition has been met. The constant speed phase Tj (figure 2) follows the constant delay phase Tj during which the moving part slows down with the same absolute acceleration value (proportional to hx and НУ, respectively, for the two axes) already used in phase acceleration T. During the phase Tj, the interpolator performs the following operations: Dx (n + l) Dxn - hyX (n + 1) xn + Dx (n + 1) Dxn, 1 micron. Inequality is used to establish the end of the phase of the apparent slowdown. To establish the start of deceleration, consider the imaginary distance of PhpM, increased in the manner described, relative to the distance traveled during acceleration, instead of considering the last at the end point, in order to ensure that the moving part does not come in the process of deceleration to the final position x, y at a speed other than zero, and therefore will erroneously continue to move beyond the point of arrival, R.,. This case, which would not have occurred in position devices from point to point, in this variant should be excluded, since it is necessary to control the entire trajectory, for example, in the case of transverse motion in order to cut the profile. It should be noted that in order to avoid this case, it is not enough to disrupt the interpolation cycle and give an order to stop the moving part as soon as the distance x - xn becomes less than the required approximation, as it can happen that the speed reached during deceleration, at this point, it remains so high that the remaining distance is not sufficient for the stop. On the other hand, in order to avoid this case, it is necessary to have a distance to slow down, equal to the distance covered during the acceleration, plus an additional spare distance sufficient to stop and, since during the T phase constant speed xh coordinate is increased by the increment DxnM, this additional distance can not be less than DxnM. Since the deceleration starts at the got moment when the distance from the end point is PJ. becomes less than the distance traveled during acceleration, plus DxnM, the moving part of the machine will have time to decelerate until the end point PJ, has passed. More specifically, it cannot reach the end point Pj, with an error greater than DxnM or DynM, respectively, for the X and Y coordinates. Therefore, it is necessary that the phase of constant deceleration does not continue until a stop occurs, but is interrupted before the stop and replaced by a slower approaching motion. to the end point of pj. It is necessary to be able to carry out this approximation movement with a constant speed, while the remaining distance X2-hp (or) reaches a limit value sufficiently small to ensure the required accuracy of the installation. interruptions and interpolations from this point. If the approach speed is too low, then a lot of time is lost. On the other hand, if the speed is chosen too high, it may be the case that the end point will be broken as the approximation moves. :. The last mentioned deficiency arises as a result of the inertia of the moving part, which will not make it possible to stop the short time, as soon as it is confirmed that the residual distance is less than the pre-selected limit, and because the positional increment Dxn derived in the interpolation cycle is greater than the required accuracy of the installation, so it can happen that during one interpolation cycle from the beginning of which the moving part did not reach the final position with the required approximation The moving part itself will pass the end point, without being able to avoid this overshoot. FIG. 2 shows a solution to this problem, in which the approximation motion is divided into two phases, Itz and Tu. During phase 4, the interpolator performs the following operations: x (n + 1) xn + D ;;;; nf XQ - xn-c 16 microns The constant positional increments are equal to the increment Dxnf achieved at the end of the deceleration phase, which is achieved during the first implementation the inequality that defines the end of the phase Tj. The end of phase T, is determined by the reduced inequality. During phase Tu, the interpolator performs the operations: X (n + l) xn + hx Xj - xn. 1 micron. The choice of the magnitude of the velocity in accordance with this ratio, although not obscure, but desirable, the Inequality determines the end of phase Tj and the end of the whole interpolation cycle. Therefore, it is clear that the phase Tj ends when during a deceleration a sufficiently low speed is reached, for example, corresponding to a 1 micron positional increment obtained in the interpolation cycle; phase T ;, ends when the driving part approaches a predetermined distance from the end point Pj; said distance, for example, may be equal to 16 microns; and the end phase TS ends when the moving part arrives at a distance from the end point less than the specified accuracy (which is taken equal to 1 micron). As soon as the moving part is at a distance less than 1 micron (required accuracy) to the end point, the interpolation is interrupted and the moving part can be stopped and fixed in the specified position by any known means, for example, a braking system or mechanical clamp. However, it is preferable that the moving part is kept in this position by the mounting servo, governed by constant positioning orders. From this point on, the positioning orders can be 1 composed of the last coordinates calculated during the interpolation or preferably so that they include the coordinates of the final points Pj that are sent by the programming device. In addition to the case shown in Fig. 2, other variants may exist, depending on the distance that must be traversed between points PI and Pj. Figure 3 shows the case when a segment comes up with the absence of a constant velocity xM in the velocity diagram, since the words in which the beginning of the deceleration phase occurs before the law. cheats acceleration phase. Therefore, moving the moving part of the machine between positions X and Xj includes the initial acceleration phase during the belt Tj between the positions and Xc, the end of which the speed is less than or equal to the maximum allowable speed, and immediately following the deceleration phase during Tj between the XQ and .xd positions: and these phases are followed by the phases Ti, and Tj-stepwise deceleration with constant speeds as described in the case of Fig. 2. Positions are determined by the existence of start-up conditions Xj-An (SDxri) tDi (n or the existence of appropriate conditions for the y-axis. Fig. 4 shows a case where the distance is greater than the 16 micron limit, although Dxn 1 micron is the same time; Under these conditions, there is an acceleration phase from Xj to Xd, followed by a constant velocity phase Vxf with a constant increment Dxnf equal to the last increment, Dxn acceleration phase. Following this, in the XQ position, there will be a phase with a constant speed Vxo from Hz to x, with Dxn hx. Figure 5 shows the case when the difference X is less than 16 microns. In this case, there is a movement between Xj and x with a constant velocity Vxo, with Dxn hx. The values of DxM h DyM, proportional to the maximum allowable speed of the moving part along the X and Y axes, are respectively provided in the form of digits from K1V to K5V. When calculating the values of hx and hy in the proposed device, the latter are matched with the values of the minimum increment of the x and y coordinates in the interpolation cycle, and the value of the angular accuracy with which the linear trajectory needs to be worked out is taken into account. Since the trajectory is calculated by accumulating increments of Dxii and Dyn, multiples of the values of by and hx, respectively, the error in calculating hx and hy distorts the trajectory that remains straightforward, since the linearity condition continues to be obeyed. the exact slope to the axes X and Y. The end point calculated by the interpolator will not match the programmed end point. If it is required that the distance between the end points does not exceed the maximum permissible error along each axis, it is necessary to limit the error in calculating the values of hx and hy accordingly. Suppose, for example, that the maximum error is 1 micron when moving in the order of 10 m. In this case, it is necessary that the increments hx and hy would be identified precision 10 microns (or in binary-coded form with an approximation equal to 2 microns). In order to calculate the values of hx and hy, it is necessary that: a) their ratio is equal ... to be; B) the indicated values would be determined with an accuracy sufficient to ensure the angular accuracy specified for the given trajectory c) the indicated values should not exceed the value corresponding to the maximum allowable acceleration. The above procedure is as follows. The values of (x - x) H and (-) H, where H is dimensionless constant, are equal to degree 2, and are set by the machine switch, and (x - x) H and (, -) H must be less than the maximum speed increment ( acceleration nor) permissible for the machine. After this value Xj. - x) H and (YJ, - y) H are multiplied and doubled with until one of them reaches the number corresponding to the maximum acceleration. Conditions a), b) and b) are fulfilled. A device that implements the stated principles receives information from tape 1, which carries the recorded program of the programming unit 2. reads information from the tape. The proposed control device also includes an interpolator 3 and a digital-to-analog converter 4, which controls the servo-mechanisms 5, 6, 7 used to move the moving part along the X, Y and Z axes, respectively. The programming unit 2 is connected to the interpolator 3 via a communication line 8. The programming unit 2 (FIG. 10) contains an input unit 9 connected to the input of the coding unit 10, connected in its turn to the input input of the control unit 11. Distributor cycles 12 connected to the control unit 11. The counter 13 is connected to the input block 9 and to the block 10. The control block 14 of the programming unit is connected to the input block to the counter 13, the operation of the control unit includes the first period during which the control block 11 feeds into interpolator The 3 previously mentioned data, i.e. the coordinates Xj and at the end point PJ of the trajectory and the maximum velocities DxM and C) uM. During this period, the moving part is fixed at the initial point Pj. Then the second period, during which the moving part remains stationary, the programming device is in an idle state, and interpolator 3 calculates the values hx and hy (when increasing speeds) on the basis of the previously mentioned principles. Then comes the third period, during which proper interpolation takes place while the programming unit remains in an idle state. In t (the third period, the interpolator of the transmission 2 7-r.;::; With flax time moves the engine from the part. For: K-oc; au iKfi along each of the axes of the stable l-: O;:; there is a separate digital converter 4, which receives the digital signals generated by interpolator 3. Output analog signal of converter 4 controls the two steps of the most important part of the machine to the corresponding axis. One conversion unit can be used for all operations: displacement. In this case, you need to transfer: reports for different axes of movement on the basis of technology from time division, i.e., signals related to the same - time period, time distribution: definition: :: pa: 1: personal axes with different promagut to the time agrarian, This is sk; .zola ;; czech ;; shown in Fig. 6, where three pairs of switches are shown, including perceptually, to power the digital-to-analogue converter 4 and the SERIO: 5, 7, "Interpolator 3 includes a closed one. an arithmetic unit 15 connected to a write register 16 to a read register 17. The registers ib to 17 are connected respectively to the input and output of the memory block 18 by means of commutating logic: e:; kcx elements 19 and 20. The output of the memory block is; 18 is connected to the distribution system 12 (the memory unit of the memory is of the type, :: o to which type, and the operating and delay 2, 4, millisecond, n, yg can contain max-g; / .: 2400 bits with a cycle duration of 1 rv-microsecond), the Interpolator control unit 21 is associated with register 16 ,. 17, with the Bzzod block 9 and the arithmetic block 15. The output of the arismatic block 15 is connected to the input of the information generator 3 parallel form 22 via a combo; 231 logical element 23, and Bfcrxcj; Converter 22 is connected to the PC. An analogue converter 4, Interpolator 3 is controlled by the signal of the clock distributor 12, which allows us to determine the bit number of each bit appearing at the output of the blinker and 18 , In the magnetostricted naMiiTK example, 2160 bits of information circulate, which takes 2160 microseconds from 2.4 MTij-shisekukd valid shutter speeds of 5p; .genera, the clock distributor 12 is driven from the first bit, which appears at the output of memory block 18. to when he calculates 2160 binary, enacosis, in rabatyvaets signal Stop W ostanavlivayushy device. For each Osc, memory block 18 contains 12 ALZ.C registers. .N 50 binary bits each, total 3 X 12 X 60 2160 binary bits. The location of the binary bits for each axis will be DEOOA; DEOOB; DEOOC. DEOON; DE01A; DE01B; DE01C. . ,; DEO IN ;. . .DE59A, DE59B, DE59C, DE59N. Three groups of 12 X 60 bits, located in this way and related to the three axes, are located in the delay line one after the other. The way in which the binary characters of different registers are set is described in more detail. The bit counter 24 contained in the clock distributor 12 counts from 1 to 60, including the signals, each signal having a period of 12 times the ISS. For each of the 12 memory registers, the DEOO-DE5 signals determine the 1st, 2nd, ..., 60th bit. Digits DE01 to DE056 are used to provide numbers from microns to. 2 microns (i.e., in decimal form, values from 10 to 10 micrrn). Therefore, the position determined by the DE33 is equal to 1 micron. These 56 bit words are processed by interpolator 3. On the other hand, the coordinate data entered by the programming unit 2 contains only 24 bits, representing values from 1 micron to 10 microns. During a data entry operation through the input device 9, the indicated 24 bits with the help of the counter 24 are supplemented with zeros:: corresponding to (there are at once. For example (Fig. 12 and Fig. 13) 24 bits X 2 (representing values from 1 micron to 2 microns) are entered into register D into binary bits of the DE33-DE56. Similarly, 24 bits, representing the magnitude of the maximum gain (maximum allowable speed) and corresponding to values from 2 microns to 2 microns, are entered into register B bit DE20-DE43. Obviously, in the case when the interpolator is used to control the machine, this speed range is excessive, and 14 significant binary bits from 30 to 43 are enough for normal use, representing the maximum increment between 2 microns and 2 microns; whereas the coordinate output from the interpolator takes place every 5 milliseconds and the speed variation range is in the range from 1.4 mm per minute to 12.288 m per minute, which is quite enough for any common applications. DE57 is used to store the sign of a number. More precisely, this bit is used to distinguish between positive and additional numbers. DE58 bit is used for accumulated carry. The DE59 and DECOO bits remain free in all memory registers and act as a partition section (the bits between the registers of different axes, thus avoiding transfer from one axis to the next axis. First, all information related to the X axis (12 X 60 720 bits in total) is recorded in the memory, then to the Y axis and, finally, to the Z axis. Counter 24 repeats three times the reading of 60 binary characters for each address X, Y, Z. The time related to the three addresses is determined by the three signals iNiC, iNiP, iNAZ, KO, which are generated by the second counter 25, controlled by the counter of bits 24. The third counter 26, controlled by the end-of-count signal of the information supply, triggers its output signals CiRi, CiRi, and therefore the period of the CiRi signal is equal to two information cycles in memory block 18, and this period determines the duration of the DT interpolation cycle. As can be seen from the diagram of the external computing unit, the memory is equivalent to a device of six adders in parallel, A, C, E, S ,. I and M plus six other parallel-connected adders B, D, F, H, L, and N having. inputs and outputs are common with the first six adders, respectively, and a common phase with respect to the first six adders. The fourth counter 27, which receives signals from the generator 28, cyclically emits clock pulses at six outputs T10-T15 with a period equal to 1 microsecond. Binary counter 2 :, controlled by signal T10, has two outputs G1 and G1, defining two different cycles of counter 27 with a period of 12 microseconds, the signal G1 activating counter 24. Therefore, a pair of signals from counter 27 and counter 29 determines one of adders A - M. FIG. Figure 9 shows a pair of signals defining each accumulator of memory block 18. Fig. 8 refers to the arrangement of various values in the memory registers during the input phase, while Fig. 9 illustrates the arrangement of information in the memory registers during the calculation phase. The memory registers operate as follows with respect to the X axis. The programming unit 2 can provide two alternative modes, in the first of which the input unit 9 enters data into the memory unit 18, and secondly the arithmetic unit 15 performs interpolation. During the interpolation (Fig. 8), the register A serves to store the value of the distance traveled XYj-x, during the entire acceleration phase Y and, in addition, stores the value PxpM obtained at the end of the phase T. In register B, the maximum increment DxM is entered during the input phase from the programming block (maximum speed along the X axis is allowed). This value, previously recorded in the DE17-DE40 binary bits of register B, is then shifted by three bits into the DE20-DE43 bits, where it is kept unchanged until the programming unit enters another value or performs variables of this value. The register X during the input phase receives the coordinate Xj of the end point R., whose value is shifted forward by tog H 33, the binary bits of the remaining significant bits. Therefore, register C may contain the value H – x required to calculate the speed increment hx. The coordinate Xs of the end point Pj is entered into register D. and remains unchanged in register D during the entire interpolation in order to calculate the remaining distance, which must be passed before stopping at the end point of the straight segment of the trajectory. At the end of the interpolation of the path segment, the contents of My register D are transferred to the register L and stored there for use as the initial x coordinate, the next linear segment. The programming block provides only the final coordinates of the straight-line segments. Register E contains the increment of the speed DX in the interpolation phase rotation (FIG. 9). Register F contains 1/8 DxM values during the input and interpolation phases; this value is entered in register F in D O.N. DE1-DE4 bits. The 1/8 pxM value is used to change the maximum advance or feed rate. During the data entry phase, the DxM value characterizing the feed rate is entered into memory register B, while 1/8 value. OXM is entered into register F. The DxM value serves as a comparison test to establish the end of the acceleration phase Ti and start The Ti constant rate phase of a 1/8 DxM Be-rate is used as an increment to modify the value of register B by means of a subtract operation. As soon as the magnitude of the velocity change is calculated, it begins to be processed, which is performed synchronously with p Since each interpolation cycle consists of two cycles / one of which is intended for benchmarking and the other for computational operations, the calculation of the change in feed rate is performed by incrementing the speed DxM by successive steps, each of which contains two memory cycles one, one prediagnan for scanning the sign of the desired increment, and the second intended for incrementing DxM by an increment of 1/8 DxM. The contents of the L register, consisting of the initial x coordinate, the next rectilinear segment, is entered from the D register at the end of the interpolation, accumulating bit by bit during the interpolation, so that the L register contains consecutive values of the instant x x coordinate. Register L is used to act on a servo system and is only a memory register whose inputs are connected to converter 4. The functions of the remaining registers are explained below. On the flg. 8 and FIG. 9 dotted lines related to registers B ,. C and D represent a group of 2-. neighboring bits among the 56 bits of each register in which the corresponding data from the programming block is entered, while the dotted lines belonging to the registers F, I, L represent 24 neighboring bits, in which data of the oc tc is contained in the registers B, C and D, respectively The functions and contents of the registers related to the axes Y and Z are similar. Calculate speed for the next segment. The device comprises a computing unit 30 (FIG. 10) for controlling the repetitive method of operation, in which the stop at the break points of the segmented line does not take place. A selection of the mode of operation can be made for each straight-line segment of the trajectory. For example, store a special auxiliary function encoded on a programming tape along with the time data relating to the new line break point: in the first receive register 35, to determine whether the break point should be passed with a speed, lie equal to zero. Consider in more detail (Fig.7) two segments of the trajectory Pj - Pi and Pj - RZ having a common point of discontinuity Pj. By.: Let's return, that the stop at the point P was not made, but it is necessary to go the way PJ -P - RZ with a continuous speed. In this case, the end part of the P segment, - P., runs at a constant speed equal to the speed during the next phase Tg of the segment, i.e. the final phase (Tj and the following phases) of the retardation is eliminated. In turn, the initial part of the PJ – P segment is run at a constant rate, and the acceleration phase T of the Pj – Pj segment eliminates the SI. In addition, steps are taken to ensure that the moving part is not subjected to too large fluctuations of speed as it passes through the point of breakdown of P. Of course, the initial parts of the segment of PI - P and the final parts of the segment of Pg. - RZs can be carried out according to the acceleration phase or the deceleration phase, if a stop is provided at the points PJ and Pj. When there should be no stop at point P, the interpolation phase relating to the PI-Pf segment coincides in time with the phase of calculating the positional increment (DxB, DyB) used in the Pj-P segment. Therefore, it is clear that, although the interpolator specifies the positions in the P segment of the P segment. - P in real time, the positional increments (DxB, DyB) for the next Pj segment must be precomputed. Since the Pj - P segment can be very short, the method of calculating positional increments of- (DxB, DyB for the next segment of Pg-Pj, differs from the previously described one. In order for the calculation to be completed before the decisive part reaches the break point P , it is necessary to increase the speed of the calculations. Calculations of the increments of DxB, DyB are performed as follows: In order to obtain a given slope of the segment Pg - Pj, the condition x, DyB and g should be fulfilled. In addition, the differences DxB - DxM and DyB - DyM, where DxM and DyM are maximum speeds, they should not exceed the maximum of a positive value. More precisely, the goal is to minimize the deviation in the speed of passage along the axis through the break point PJI at the highest possible speed. For this, the device contains an arithmetic unit 32 formed of a decisive element 33 (see FIG. 35 (Fig. 11), while enabled for simultaneous execution of operations. Arithmetic node 32 (Fig. 10) is connected to the write and read registers 16 and 17 h through the output and input registers 36 and 37, controlled by the clock distributor 12. Node 38 local device connected to the arithmetic unit 32 and the control unit 14 of the control unit, to the clock distributor 12 and to the output and input registers 36, 37. The computing node 30 includes the second receive register 39 connected to the control unit 1.1, the clock distributor 12 and the input ancillary data to the write register 16. During data entry through input block 9, when the maximum speed DxM, DyM is read from the tape, the logic element O contained in the second receive register 39 (fig.11) gated by signals T ", G1 to record in the last two In this case, the memory cycles of 1/128 | .OhM and 1/128 DyM values, related respectively to the X and Y axes, and controlled by the signals DE16 - DE48, which ensures that the maximum speed in the register B is entered into the G register (fig.9 ), shifted by 92–127 7 bits. By the beginning of the phase of interpolation of the segments Pr. - PA (Fig. 7) is used to read block data related to the RP point. In particular, the coordinates x3 and yJ, counted in this way, are recorded by logic element 41 (Fig. 11), gated signals, G1 and controlled. The DE33-DE56 registers of the M registers (Fig. 9), corresponding to the axes X and Y, respectively. The other logic element 42 (Fig. 11) is gated with signals T-jj g G1 and controlled by the bits DE01 - DE24 of the registers N ( Fig. 9), respectively, related to the axes X and Y. Based on the foregoing, it is clear that entering data into bits DE33 - DE56 of register M corresponds to preserving the original value of the number, whereas entering data into bits DE01-DE24 corresponds to entering to registers N, respectively, of Hx and Nua values, where H 2. At the end of the data entry, point Pj and during the interpolation of the P PI segment ION AND gates 43 and 44 included in the register 37, the drive signal A output from the local control unit 38, the values of Hx Hxj and transmitted to the deciding portion 33 calculating a difference HXj - K x N and US - NU2. This result, denoted by hx and hy, under the control of logic element 45 from register 36 gated with signals T ,, and G1 and signal AJ, is entered into registers M of memory unit 18. Local control node 38 also provides signal A which is transmitted in memory. In particular, the value of the G memory register, i.e., 1/128 DxM and 1/128 DyM, respectively, is inputted into the decisive element 33 under the control of the logic element 46 from the register 37 gated with the signals T "and G1. Signal.al AJ, in turn, via logic element 47, excites displacement control unit 48 in order to enter the contents of memory register H, i.e., the values hx and hy to decisive element 33, scored one bit in the direction of the higher bits. The decisive element 33 compares the contents of the register G (Fig.9) with the contents of the register H, shifted in this way. So, hx and hy are successively multiplied by 2 until the next result is obtained. one, . -Dxm -one . -DyM With hx and hy and stop after any of these conditions. in particular, if they do not take place, that is, in the case when hx 1/256 DxM, respectively hy 1/256 DyM, the logic element 49 provides registration in memory block 18 shifted by one bit the value of register F entered in solvable element 33. If one of these conditions occurs, then the logic element 50 registers the value of the register H, i.e. hx and hy, since it is in the same register, as a result of which the transfer is stopped. The values of hx and hy thus obtained will be referred to hx and hy respectively. Then hx and hyi. respectively, fold several times until one of the conditions is met DxM ShXi or DyM Shyi. between the sums Shxj and Shyi by the cumulative takgm path, and the maximum increments of DxM and DyM. In order to accelerate the accumulation of the values Shxi and Shyi, the local control node 38 contains the time delay element 51, 52 and 53 to which information is fed from the auxiliary register 54, excited by the signal AJ, when the first group of conditions is reached, at time T, G1. Thus, hx, hyi j delay element 51 delays the signals by seven clock cycles, thus producing 128 hxj and 128 hyi; delay element 52 delay ;; signals on four cycles, thus producing values of 16hXt and 16hyi; the delay element 53 delays the signals on one clock cycle, thus producing a value of 2hx and 2hyi, First of all, the signal Aj through the logic element 55 and the delay element 51 activates the decision element 33, which receives the sums hxi + l28hX (, Shxt and hyj. 128hyi Shy "registered by means of the logic element 55 in the register of the memory block 18. The sums Shx and Shy o are compared by comparison circuit 34 with DxM and DyM values, respectively. These values are obtained by reading from the register F a delay of three cycles of read values using 5 delay element 56. Block 57 issues a Signal AC in case none of the above conditions of the SECOND group is fulfilled, and issues a signal As in the event that one of these conditions occurs. Signals A and Hell through 0 logic element 58 and trigger 59 emit a signal Ag, blocking the accumulation, and through logic element 60 set the trigger 61, the output 5 signal A of which, controlling the logic element 62, causes registration of the values Shx, Shy in the memory block 18 and adding the value (16hx) to the sum (hxi 128. pu), and the values (16. hy) are repeated to the sum 0 me (hy 4-128 hyi). In this case, the comparison circuit 34 .. controls the occurrence of one and, for the aforementioned conditions of the second group. The comparison circuit 35 subtracts the values of 16 hx and 16 hy, respectively, from the values of DxM and DyM, while the comparison circuit 34 controls the presence of one of the conditions ShX | DxM - 16 hx: DyM - 16 hy; , If these conditions do not hold, then the summation of the values of 16 hx and 16 hy; repeat. When one of the mentioned conditions occurs, the comparison circuit 34 causes the generation of the signal AJ, which, in combination with the signal A, sets the trigger 63. The output signal Ag of the trigger 63 activates in the decision element 33 the repeated addition of the values and and the writing of the sum in the register - And through the logic element 64, while the comparison circuit 34 again controls the second group of the above conditions. When one of these conditions occurs, the signal Aj through the logic element 65 triggers the generation of the flip-flop 59 of the signal A, thus terminating the accumulation. As a result, for the axis where the accumulated stopping condition is met, the final accumulation differs from DxM or DyM by a value between 1/64 and 1/128 DxM or DvM. On the jroyroi side, for the other axis, the deviation between the accumulated amount and the corresponding maximum speed is larger. Thus accumulated for the X and Y axes, the final sums are registered in the H register and consist of the positional increments of DxB and DyB, which should be used on the Pj –R segment. As the increments of Rit by bit during the interpolation instantaneous speed, it is clear that when passing through the break point Pj, the velocity along one of the axes n-e will have a significant discontinuity, while along the other axis the velocity deviation is greater, the greater the difference between the angle of inclination of the segment P., - P segme ntu Ptf P Since the RZ data is read from the tape at the end of the PJ data, i.e. at the beginning of the interpolation of the Pj-Pj segment, the speed of the moving point can be chosen larger than the deviation in the slope of the path. To calculate the increments of DxB and DyB that occur during the PI-PI path, it is also necessary to have relative coordinates relative to the Pb point in order to account for inclination (the P-P segment, therefore, it is necessary to have a register G in the interpolator memory , H, M, N for data related to the next RE segment - Pj. At the same time as the interpolator controls in real time the movement along the current Pj PI segment. The reading time of the coordinate from the tape plus the computation time for DxB, DyB, must be short compared with the movement time along the slender segment, which can be practically. As already mentioned, the last part of the Pj segment. - P runs at a constant speed. It can be seen from the above described description that this is achieved due to the fact that the interpolator, which operates in the current time, accumulates DxnM and DynM positional increments for two axes X and Y; DxnM and DynM are magnifying 11 F1, considered in the first part of the description. The accumulation of these constant increments, i.e. the distances traveled at a constant speed along the segment P., - PI, are determined by the presence of the DxnM Xj - xp condition or the DynM Yj yii condition under the control of the AJ signal produced by the arithmetic unit 15 (Lig.10), where xn and yn are These are the coordinates calculated by the interpolator. In other words, the path traveled at a constant speed along the segment Pj - Pj. Defines the point P ((ig.7), which lies ahead of the point Pj at a distance from it less than DxnM along the X axis and less than DynM y-axis After obtaining the final condition (the basics of constant speed (point Pj,), the signal Ad through the logic elements 66, 67 (Lig.11) causes using the intermediate register 68 to transfer the coordinates x and y from the register D to the register G, (the latter controls the servo-mechanism ) instead of the coordinates of the point R. In addition, the signal Ad through the logic elements 69, 70 causes the transfer of the coordinates Xj and y instead of the coordinates X2 and y; from register M to register D, and transferring the increments of DxB and DyB from register H to register I, in order to replace the step gain associated with segment PI - Pj. Therefore, the accumulation of positional increments in the interpolator 3 (FIG. 10) is immediately resumed. More precisely, from this point on, in the arithmetic unit 15, accumulation takes place by adding new constant increments of OHB and DyB c. each cycle of interpolation to the coordinates x and yy, which were installed in pegistras to obtain accumulation. Since before the start of the interpolation for the passage of the segment Pj. - Pj coordinates of the end point P are replaced by coordinates of the new starting point Pi (coinciding with the thermal point of the trajectory), it is clear that any errors due to the difference PJ - P do not accumulate when moving from one segment to another. After obtaining the end point Pj, the registers G, F, M and N are freed and are ready to calculate positional attributions related to the RH segment - Rc. When the DxB, DyB perutations related to the k indeterminate segment are calculated, the registers retain the results obtained in this way until the end of the path along the previous segment. If. Together with the new coordinates, the code is read from the tape. f./m x, Do an auxiliary function indicating that the driving part must stop at the point Pj, the modes in which the device calculates and controls the deceleration, as previously described, are brought back to working condition for the PI segment. Therefore, it is possible make, continuous movement of the moving part along the path recorded on the tape, simply by the coordinates of the discontinuity points P, V, P, 65 Pi (etc.).
权利要求:
Claims (3) [1] Invention Formula 1. A device for controlling a moving object, containing a programming unit, a digital-to-analogue converter, an interpolator, the first and second outputs of which are connected respectively to the inputs of the digital-to-analogue converter and the programming unit, the first, second, third and fourth inputs of the interpolator are connected to the corresponding outputs of the programming unit block, the interpolator contains a memory block, a write register, a read register, first, second and third switching logic elements, an arithmetic unit, and An information generator into a parallel form, the output of which is the first output of the interpolator, and an interpolator control unit associated with the arithmetic unit, the first and second inputs of the interpolator control unit are connected to the outputs of the write and read registers, the third input of the interpolator control unit is the first input of the interpolator, connected to the first input of the arithmetic unit and connected to the control inputs of the first, second, and third switching logic elements, the outputs of which connected to the input of the memory unit, to the input of the read register and to the input of the information converter in parallel form, the fourth and fifth inputs of the interpol control unit are respectively the third and fourth inputs of the interpolator, the second input of the arithmetic unit is connected to the output of the read register , the fifth and sixth inputs of the interpolator are connected to the input of the record register, the output of the arithmetic unit is connected to the input of the register of the record, with the second input of the third switching logic element a, the third input of the arithmetic unit is the second input of the interpolator, the output of the write register is connected to the second input of the second switching logic element, the output of the memory block is the second output of the interpolator, the output of the read register is the third output of the interpolator, which is different that, in order to increase the accuracy of the trajectory, it contains a computing unit, the first, second and third inputs of which are connected to the corresponding outputs of the programming block, the fourth input is connected to the second the output of the interpolator, the fifth and sixth inputs of which are connected respectively to the first and second outputs 1 "1 of the computing unit. [2] 2. The device according to claim 1, wherein it has a computing unit that contains an arithmetic node, a local control node, the output of which is connected to the control input of the arithmetic node, the input and output registers, the first and second reception registers, 5 inputs are connected to the control inputs of the input and output registers and the first input of the local control node and are the first input of the computing unit, the second input of which is connected to the second input of the second receive register, and the third input is connected to the second input of the local control node, the third the input of which is connected to the output of the input register and to the input of the arithmetic 5, the output of which is connected to the input of the output register and the fourth input of the local control node, the outputs of the reception register and the output register are the first and second outputs of the computing unit, the input of the input register is the fourth input of the computing unit. [3] 3. The device according to PP.1, 2, of which is based on the fact that in it 5, the arithmetic unit contains a decision element / first and second comparison circuits, the equality output of the first comparison circuit is connected to the first input of the second comparison circuit, the output of the decision element is connected to the second input of the first comparison circuit and the output of the second comparison circuit is connected with the first input of the first comparison circuit, the second and 5, the third inputs of the second comparison circuit are the control inputs of the arithmetic node. Sources of information taken into account in the examination 0 1. USSR author's certificate 165604, cl. G 06 F 15/46, 1963. 2.Ommering Rch van Schaenaker SGM, DE Cobka den ofigeta e Rekenmachine voor memericke besturing 5 van gerund-Schaps werktugen. Philips techn tijseker, 1965-1966, W 11, c. 285-298 (prototype). /one KH "| T5 TI J5 G1 ig.Z TO Vxf VitO 1 / hey Tô le k2 X / Figs ( Fig 5 X "X Fi1l Dfol J) DO J) ft7 HfSO Df2f MS3 XIO Oft /} D 24Sf33 SeiOJ) E57 DE01 yfij pego 31, j) DE53 Deod in, H-H2 with l, I} f57 VE5B DESg .PuniTZ) /, suxn (Th LhN -/one . 1/8 UK H xn Xn - / l2SuxH , hf.hxi, uxB X3 Figz
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公开号 | 公开日 US3748563A|1973-07-24| FR95797E|1971-06-25| DE1763946A1|1972-01-05| DE1763946B2|1979-01-04| GB1189959A|1970-04-29|
引用文献:
公开号 | 申请日 | 公开日 | 申请人 | 专利标题 US3109974A|1961-06-19|1963-11-05|Thompson Ramo Wooldridge Inc|Machine tool control system having feedrate control| US3390315A|1963-04-05|1968-06-25|Giddings & Lewis|Apparatus for numerical control of a multiaxes machine tool including interpolation and feedrate control|US3876873A|1971-06-07|1975-04-08|Haudaille Ind Inc|Machine tool control system and method| US3699317A|1970-05-22|1972-10-17|Westinghouse Electric Corp|Sampled data numerical contouring machine controller apparatus and method providable with on line capability for contour cornering deceleration and acceleration| GB1433868A|1972-05-06|1976-04-28|Herbert Ltd A|Automatic control systems for and methods of controlling machine tool apparatus| US3889169A|1973-10-11|1975-06-10|Ibm|Position and velocity servo control for motor controlled article carrier and handler| US4025837A|1975-06-30|1977-05-24|International Business Machines Corporation|Adaptive control circuit for a stepping motor| US4179602A|1976-07-16|1979-12-18|Shin Meiwa Industry Co., Ltd.|Method and system of velocity control for automatic welding apparatus| US4469993A|1981-03-03|1984-09-04|Swanson Systems, Inc.|Programmable multiple position machine| US4404505A|1981-03-03|1983-09-13|Swanson Systems, Inc.|Programmable multiple position machine| JPS584377A|1981-03-18|1983-01-11|Yaskawa Denki Seisakusho Kk|Controller for articulated industrial robot| JPS61156309A|1984-12-27|1986-07-16|Toshiba Mach Co Ltd|Numerically controlled device containing speed difference smoothing function| JPS61157909A|1984-12-29|1986-07-17|Fanuc Ltd|System for correcting route error of robot| JPH0732979B2|1987-06-17|1995-04-12|ファナック株式会社|Acceleration / deceleration control device| JP2694669B2|1989-06-09|1997-12-24|株式会社日立製作所|Robot motion control method| US5229698A|1990-08-06|1993-07-20|Cincinnati Milacron Inc.|Method and apparatus for sub-span interpolation| US5448145A|1991-09-09|1995-09-05|Fanuc Ltd.|Feedforward control method for a servomotor| KR970003877B1|1991-09-09|1997-03-22|화낙 가부시끼가이샤|Method of controlling feed-forward of servo motor| DE69113249T2|1990-11-08|1996-02-22|Fanuc Ltd|METHOD FOR CONTROLLING A SERVO MOTOR WITH FORWARD CLUTCH.| FR2682905B1|1991-10-28|1995-12-01|Commissariat Energie Atomique|PATH GENERATION METHOD FOR A ROBOTIZED SYSTEM.| US5438522A|1992-12-18|1995-08-01|Cincinnati Milacron Inc.|Method and apparatus for sub-span interpolation| US5426722A|1993-09-09|1995-06-20|Stratasys, Inc.|Method for optimizing the motion of a multi-axis robot| JPH08211815A|1995-02-02|1996-08-20|Canon Inc|Coating applicator and process cartridge and image forming device| JPH10320026A|1997-05-20|1998-12-04|Mitsubishi Electric Corp|Device and method for numerical control| JP3352986B2|1999-12-17|2002-12-03|スター精密株式会社|Machine tool drive control device| GB0508273D0|2005-04-25|2005-06-01|Renishaw Plc|Method for scanning the surface of a workpiece| JP4467625B2|2008-03-31|2010-05-26|三菱電機株式会社|Numerical control apparatus and numerical control method| US11014237B2|2019-07-11|2021-05-25|Intelligrated Headquarters, Llc|Methods, systems, and apparatuses, for path planning and execution in a robotic system|
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申请号 | 申请日 | 专利标题 IT2044065|1965-09-03| IT5307567|1967-09-19| 相关专利
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