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Stepper motor driving through conventional on-line control algorithms falls to produce a high-speed rate. In recent years this has become an issue, especially when applications involve microstepping drives. In this work an analysis of the problem is presented and a new algorithm is proposed that does not have the speed restriction of the convention...
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... motion control applications in which a load must a (n) current acceleration be moved precisely involve high-speed positioning of a (n) down current downward acceleration stepper motors. Precise positioning requires the use of a (n) up current upward acceleration velocity prooles, which must be adjusted to a certain A max maximum motor acceleration performance in speed and acceleration as well as the C 1 , C 2 , C 3 , C 4 constants specifying the velocity dynamics of the system in order to guarantee motion proole without step-loss. The prooles can be trapezoidal, k current step sinusoidal, parabolic or arbitrary according to the n current iteration application [1]. n k number of T c cycles in the kth step Stepper motors are suitable for precise positioning N total number of steps since motors with small steps are commonly available. ¢t (k) time of the kth step When further precision is required, microstepping is a T c iteration time technique in which the motor step size is reduced. The T hold stepper motor holding torque most important drawback of this technique is that T r timer resolution shorter pulses are now required for obtaining the same v (n) current velocity rotor speed as full stepping [2, 3 ]. Thus there is a need V (k) resulting velocity proole for an optimized algorithm for producing pulses at a V max maximum motor velocity very high rate. V r(k) reference velocity A general system for commanding of a stepper motor is shown in Fig. 1. There are three functions: (1) the velocity proole generation block, (2) the indexer block and (3) the power drivers. Blocks (1) and (2) After the velocity proole is generated, it has to be trans- lated into pulse intervals by the indexer. Each index pulse means that the motor must increment its rotor position in one microstep, hence the name indexer. This block is unique to commanding of incremental motors since other types of motors can be commanded simply by applying the velocity proole in the form of current or voltage. Implementation of the controller in Fig. 1 can be performed by two alternatives: o-line or on-line schemes. In the o-line schemes the timing of the microsteps is calculated prior to the movement [4, 5 ]. The velocity prole and the time space between pulses are calculated and then stored in some kind of memory media bundled is the indexer of Fig. 1. Often a common block is shared into the hardware, i.e. ROM (read-only memory) or even because a single equation computes both the velocity hard ...
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... motion control applications in which a load must a (n) current acceleration be moved precisely involve high-speed positioning of a (n) down current downward acceleration stepper motors. Precise positioning requires the use of a (n) up current upward acceleration velocity prooles, which must be adjusted to a certain A max maximum motor acceleration performance in speed and acceleration as well as the C 1 , C 2 , C 3 , C 4 constants specifying the velocity dynamics of the system in order to guarantee motion proole without step-loss. The prooles can be trapezoidal, k current step sinusoidal, parabolic or arbitrary according to the n current iteration application [1]. n k number of T c cycles in the kth step Stepper motors are suitable for precise positioning N total number of steps since motors with small steps are commonly available. ¢t (k) time of the kth step When further precision is required, microstepping is a T c iteration time technique in which the motor step size is reduced. The T hold stepper motor holding torque most important drawback of this technique is that T r timer resolution shorter pulses are now required for obtaining the same v (n) current velocity rotor speed as full stepping [2, 3 ]. Thus there is a need V (k) resulting velocity proole for an optimized algorithm for producing pulses at a V max maximum motor velocity very high rate. V r(k) reference velocity A general system for commanding of a stepper motor is shown in Fig. 1. There are three functions: (1) the velocity proole generation block, (2) the indexer block and (3) the power drivers. Blocks (1) and (2) After the velocity proole is generated, it has to be trans- lated into pulse intervals by the indexer. Each index pulse means that the motor must increment its rotor position in one microstep, hence the name indexer. This block is unique to commanding of incremental motors since other types of motors can be commanded simply by applying the velocity proole in the form of current or voltage. Implementation of the controller in Fig. 1 can be performed by two alternatives: o-line or on-line schemes. In the o-line schemes the timing of the microsteps is calculated prior to the movement [4, 5 ]. The velocity prole and the time space between pulses are calculated and then stored in some kind of memory media bundled is the indexer of Fig. 1. Often a common block is shared into the hardware, i.e. ROM (read-only memory) or even because a single equation computes both the velocity hard ...
Context 3
... motion control applications in which a load must a (n) current acceleration be moved precisely involve high-speed positioning of a (n) down current downward acceleration stepper motors. Precise positioning requires the use of a (n) up current upward acceleration velocity prooles, which must be adjusted to a certain A max maximum motor acceleration performance in speed and acceleration as well as the C 1 , C 2 , C 3 , C 4 constants specifying the velocity dynamics of the system in order to guarantee motion proole without step-loss. The prooles can be trapezoidal, k current step sinusoidal, parabolic or arbitrary according to the n current iteration application [1]. n k number of T c cycles in the kth step Stepper motors are suitable for precise positioning N total number of steps since motors with small steps are commonly available. ¢t (k) time of the kth step When further precision is required, microstepping is a T c iteration time technique in which the motor step size is reduced. The T hold stepper motor holding torque most important drawback of this technique is that T r timer resolution shorter pulses are now required for obtaining the same v (n) current velocity rotor speed as full stepping [2, 3 ]. Thus there is a need V (k) resulting velocity proole for an optimized algorithm for producing pulses at a V max maximum motor velocity very high rate. V r(k) reference velocity A general system for commanding of a stepper motor is shown in Fig. 1. There are three functions: (1) the velocity proole generation block, (2) the indexer block and (3) the power drivers. Blocks (1) and (2) After the velocity proole is generated, it has to be trans- lated into pulse intervals by the indexer. Each index pulse means that the motor must increment its rotor position in one microstep, hence the name indexer. This block is unique to commanding of incremental motors since other types of motors can be commanded simply by applying the velocity proole in the form of current or voltage. Implementation of the controller in Fig. 1 can be performed by two alternatives: o-line or on-line schemes. In the o-line schemes the timing of the microsteps is calculated prior to the movement [4, 5 ]. The velocity prole and the time space between pulses are calculated and then stored in some kind of memory media bundled is the indexer of Fig. 1. Often a common block is shared into the hardware, i.e. ROM (read-only memory) or even because a single equation computes both the velocity hard ...
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Citations
... Stepper motors have a wide range of applications. Some applications require that a stepper motor should rotate continuously or periodically with a constant speed or a variable speed; some applications also require that it should position a device at the right time to a certain position according to a program [4,5]; some of them require accelerating or decelerating motions up to a certain speed; some require mixed motions of them and etc. [6,7]. When these different motion types are taken into account, developing a computer program for programming and controlling the stepper motors is a practical and wise way. ...
Stepper motors are a digital actuator whose input is in the form of programmed energization of the stator windings and whose output is in the form of discrete angular rotation. It is, therefore, ideally suited for use as an actuator in computer control systems, digital control systems and etc. Control systems employing stepper motors as actuators are known as incremental motion control systems. In this study both a GUI and a programming page driven from Matlab program are developed for programming and controlling different types of stepper motors at different drive modes. The parallel port of a PC is used to drive stepper motors. By means of this software, stepper motors having up to 8-separate-excitating signal can be programmable and controllable easily. In the software many different rotational motions are defined as built–in functions. In addition, it provides that the user can define new built-in functions, too. It can be, also, considered as a learning aid system for students to get a comprehensive understanding of stepper motors.
... An analysis of applications involving simultaneous control of multiple stepper motors, where on-line control algorithms fail to produce a high speed step rate, is presented. An algorithm [11] is applied which does not have the speed restriction as the conventional ones and does not require hardware timers. The implementation presented, yield computing time speeds up to 15 times smaller than typical on-line algorithms. ...
... Equations (5) and (9) are replaced by (11) . Although, this means no changes in the algorithm, it reduces the pair of multiplications to only one. ...
... The COUNTER, wich counts clock periods, represents the execution of (5). The hardware implementation of (11) is carried out by the MULTIPLIER and the COMPARATOR (11) When the inequation is satisfied, a new step is commanded. The signal is then fed to the DRIVER INTERFACE, which commands the pulses to the driver of each motor phase. ...
... An analysis of applications involving simultaneous control of multiple stepper motors, where on-line control algorithms fail to produce a high speed step rate, is presented. An algorithm [11] is applied which does not have the speed restriction as the conventional ones and does not require hardware timers. The implementation presented, yield computing time speeds up to 15 times smaller than typical on-line algorithms. ...
When the applications involve the simultaneous control of multiple stepper motors conventional on-line control algorithms fail to produce a high speed step rate. An analysis of the problem is presented and an algorithm [Proc IMechE Part I: J Systems and Control Engineering 217 (2003) 359] is applied which does not have the speed restriction as the conventional ones and does not require hardware timers. The developed algorithm was tested on a hardware where several motors must be controlled simultaneously and comparative results were obtained.
