JP4682907B2 - Motor control device - Google Patents

Description

The present invention, Ri apparatus der utilized for robots and industrial equipment, a motor control device for linear interpolation operating a plurality of motors.

Conventionally, when controlling multiple motors simultaneously in robots, conveyors, machine tools, etc., the host controller always monitors the positional relationship of each motor so that their axes do not interfere with each other and their relative positions do not shift. Interpolation control for correcting the position is performed (for example, see Patent Document 1).
JP 2001-35385A

  The problem to be solved is that the interpolation control of a plurality of motors is complicated and difficult to adjust.

  In general, when the host control device performs interpolation operation control while monitoring the positional relationship of each motor, the device becomes complicated, which increases costs, makes adjustment difficult, and requires advanced algorithms in many cases. A lot of knowledge and experience was necessary to use it.

  In addition, if a communication network is used to synchronize a plurality of motor operations, the apparatus becomes complicated and the cost further increases.

  The present invention solves the above-described conventional problems, and an object thereof is to provide a motor control device that can easily perform linear interpolation control at low cost.

In order to solve the above problems, the present invention is a motor control device equipped with a numerical control function for generating operation commands for a plurality of motors, and previously stores a movement distance, acceleration time, deceleration time and movement time to a target position. And an operation command generating means for generating a motor operation command based on the travel distance, the acceleration time, the deceleration time, and the travel time stored in the data storage unit, and the motor operation command Is a motor control device that controls the target position arrival timing, and further updates the storage contents of the data storage unit by external communication means, and further stores the movement time per unit moving distance in the data storage unit in the device,
When the motor operation is interrupted and restarted next time, the motor control device performs the motor operation from the intermediate point to the target position using the movement time per unit movement distance .

  According to the motor control device of the present invention, since the target position arrival timing can be easily controlled based on the motor operation command, simple interpolation control can be performed.

  Further, since the stored contents are sequentially updated by the communication means, the positioning operation can be performed at a low cost without being limited by the data storage capacity in the motor control device.

  Furthermore, if the movement time per unit movement distance is stored, the interpolation control can be continuously performed after the restart even if, for example, the movement is temporarily stopped during the movement.

  Therefore, a motor control device capable of performing simple linear interpolation control of a plurality of motors at low cost and easily can be obtained.

  A data storage unit that stores a movement distance, acceleration / deceleration, and movement time to a target position in advance, and an operation command generation unit that generates a motor operation command based on the stored movement distance, acceleration / deceleration, and movement time. The storage contents of the data storage unit are updated by the communication means, and the target position arrival timing is controlled based on the motor operation command.

  The motor control apparatus according to the first embodiment will be described with reference to the drawings.

  In FIG. 1, the motor control device 1 receives a command from the host control device 11 and generates an operation command in the operation command generation means 2. The command from the host controller 11 is performed by, for example, an open collector signal from a sequencer or a serial communication signal.

  The operation command is generated based on data stored in advance in the data storage unit 3. The motor control device 1 has external communication means 6 and communicates with the host control device 11 and a personal computer.

  As shown in Table 1, the data storage unit 3 previously stores a movement distance 21, an acceleration time 22, a deceleration time 23, and a movement time 24 for each movement point.

For example, the point number shown in Table 1 is sent from the host control device 11. When the command to move to 1 is received, the motion command generating means 2 The value set in the first row is read from the data storage unit 3, and an operation command 25 as shown in FIG. 2 is calculated.

  The generated operation command 25 is sent to the servo control unit 4, and a command for actually operating the motor 12 is generated together with the position and speed detection based on feedback information from the encoder 13 to drive the inverter circuit 5. . The motor 12 operates a predetermined moving distance with the set acceleration / deceleration time and moving time.

  The present invention is particularly effective when linear interpolation control is to be performed by operating a plurality of motors simultaneously, and the application operation of interpolation control will be described with reference to FIG.

  Consider a case where the workpiece 39 is moved from the origin 31 to the target position 32 by using two motors 33 and 34. It is assumed that the motor 33 is used for an axis that operates in the X direction, and the motor 34 is used for an axis that operates in the Y axis direction.

  It is assumed that the workpiece is connected to these two motor shafts and can move to any point on the XY coordinates.

  When moving from the origin 31 to the target position 32, the moving distance 34 of the motor 33 and the moving distance 36 of the motor 35 are different, but in order to move the work 39 smoothly at the shortest distance, the positions are moved to the positions 32A and 32B simultaneously. Need to reach.

  In the conventional interpolation control method, since the host controller monitors each motor position information and performs interpolation control of two motors, a complicated control algorithm and an advanced controller are required. Since the motor control device 1 of the invention can be operated by specifying the movement time, if both the movement times of the motor 33 and the motor 35 are set to the same value, for example, 5 seconds, a complicated device or algorithm is not used. After 5 seconds, the target position 32 (intersection of position 32A and position 32B) is reached.

  In this way, simple interpolation control can be realized easily and at low cost, and the workpiece can be moved within the shortest straight line distance.

  The motor control apparatus according to the second embodiment sequentially updates data in the data storage unit through communication with a host control device or a personal computer via an external communication unit, and uses a rewritable memory in the data storage unit. The rest is the same as in the first embodiment, and a detailed description thereof is omitted.

  As described in the first embodiment, when the motor positioning operation is performed, the data storage unit 3 previously stores the movement distance 21, the acceleration time 22, the deceleration time 23, and the movement time 24 for each movement point, and then starts the operation. However, the data capacity that can be stored in the data storage unit 3 is limited.

  It is assumed that the data storage unit 3 of the first embodiment has a memory capacity that can store only 10 types of positioning points. In the second embodiment, a rewritable memory is used as the data storage unit 3, and the contents of the data storage unit 3 are sequentially updated by the external communication unit 6. The operation command generation means 2 generates an operation command based on the updated data, and can perform positioning control at a position of 11 points or more.

  As described above, the motor control device 1 according to the second embodiment generates the operation command 25 by the rewritable data storage unit 3 and the external communication unit 6 without being affected by the memory capacity of the data storage unit 3. It is possible to perform an unlimited positioning operation.

  The motor control device according to the third embodiment makes it possible to resume the positioning operation from the middle when the operation is interrupted for some reason during the operation.

  As in the first embodiment, if the unit of the movement time of the data storage unit 3 is ms, when the motor operation is interrupted halfway and the operation is resumed next time, from the halfway point to the target position in the initial movement time. The operation is resumed, and position interpolation control between a plurality of motors cannot be performed.

  In order to solve this problem, the third embodiment stores the travel time per unit travel distance in place of the travel time in the data stored in the data storage unit 3 (for example, as shown in Table 2, the rotary encoder 13 Is stored as the travel time per pulse).

Point No. shown in Table 2 Considering the case of moving by designating 1, the total moving time is 5000 (pulse) × 10 (ms / pulse) = 50000 (ms). Temporarily, point no. Even if the operation is interrupted while moving to 1, if the operation is resumed next time, it can move in a time corresponding to the distance from the interruption point to the target position.

  Thus, even when position interpolation control is performed between a plurality of motors, interpolation control can be resumed from the interrupted position.

  The motor control device of the present invention can easily perform interpolation control of a plurality of motor operations, and is useful for a transport device or a machine tool that operates a plurality of axes simultaneously.

Block configuration diagram of the motor control device of the present invention Explanatory drawing of operation command of the present invention Explanatory drawing of application operation in linear interpolation control of the present invention

DESCRIPTION OF SYMBOLS 1 Motor control apparatus 2 Operation command production | generation means 3 Data storage part 4 Servo control part 5 Inverter circuit 11 High-order control apparatus 12 Motor 13 Encoder 21 Movement distance 22 Acceleration time 23 Deceleration time 24 Movement time 25 Operation command 26 Maximum speed 31 Origin 32 Target Position 32A Position (X coordinate)
32B position (Y coordinate)
33 Motor (X axis)
34 Movement distance (X axis)
35 Motor (Y axis)
36 Travel distance (Y axis)
39 Work

Claims (1)

A motor control device equipped with a numerical control function for generating operation commands for a plurality of motors, a data storage unit for storing a movement distance to a target position, an acceleration time, a deceleration time, and a movement time in advance, and the data storage unit A motor having operation command generating means for generating a motor operation command based on the stored movement distance, acceleration time, deceleration time, and movement time, and controlling a target position arrival timing based on the motor operation command; In the motor control device which is a control device, and further the storage content of the data storage unit is updated by an external communication means, and the data storage unit stores the movement time per unit movement distance ,
A motor control device that performs a motor operation from the midpoint to the target position using a travel time per unit travel distance when the motor operation is interrupted and restarted next time .