Data processing: structural design – modeling – simulation – and em – Simulating electronic device or electrical system
Reexamination Certificate
2001-04-16
2004-10-12
Thomson, William (Department: 2123)
Data processing: structural design, modeling, simulation, and em
Simulating electronic device or electrical system
C703S020000, C703S024000, C703S002000, C700S097000, C700S029000, C700S030000, C700S031000
Reexamination Certificate
active
06804636
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a technique supporting development of a servo control part (servo control program) of a control program for a product of a relatively small size and having rapid response. Particularly, the present invention relates to a control program development support apparatus suitable for use when a servo control program (firmware) for every product requiring a precise servo control such as amagnetic disk drive (HDD), an optical diskdrive (CD, MO, DVD, MD), amagnetic tape unit (DAT, VTR), an NC machine tool, etc.
2. Description of the Related Art
When a mechanism having an actuator (motor) and a sensor, and operating three-dimensionally is designed, a plan of the mechanism is first worked out. Then, detailed design, drawing issue and parts preparation are done, the parts are assembled to built a prototype, then operations and the like of the prototype are evaluated, in general. After that, a process of changing the design according to a result of the evaluation, manufacturing a prototype whose design has been changed, and again making evaluation is repeated. When a result of the evaluation is satisfactory, the design is completed.
In order to operate the mechanism designed as above, a control program for controlling the mechanism is generally developed. The control program is executed by a microcomputer built in the mechanism that is a controlled object. Hereinafter, the above control program executed by the microcomputer is occasionally referred to as a built-in software.
When the above control program (built-in software) is developed, it is heretofore necessary that a trial product (prototype) of the mechanism to be controlled is completed. Namely, the mechanism can be operated only after the trial product is completed, and development of the built-in software using the trial product can be initiated.
Development of the built-in software is done in the following manner while the trial product is actually operated after the trial product is completed. First, rough design of the built-in software is made, detailed design is made on the basis of the rough design, a built-in software is created by coding a result of the detailed design, and the built-in software is debugged.
Meanwhile, construction and validation of the servo mechanism of the firmware is heretofore done by using an actual mechanism (prototype), like development of a built-in software described above.
When construction and validation of the servo mechanism of the firmware is done in the above manner, inspection can be done only after a prototype is completed, a cost and a time are therefore required for the development, which is inefficient. In addition, inspection using a prototype causes such a disadvantage that even when a firmware program is stopped due to an event break or the like, a motor configuring the servo mechanism keeps rotating so that step debugging is impossible.
Further, a servo mechanism control program for a product produced on the order of tens of thousands per month has to be able to cope with variations in mechanism to a certain degree. In development using an actual mechanism, it is difficult to obtain a mechanism in a desired state considering the above variations, and it is also difficult to know how much the firmware can cope with variations.
For this reason, it is desired to effectively develop (construct, validate) a firmware without using a prototype by making a virtual model on a computer and controlling the model by an actual firmware. If such a technique is realized, anticipatory development becomes possible, use of a step debugging function or the like becomes possible since an actual motor is not used, a novel control technique using a new actuator or sensor can be simply validated without making a prototype.
There has been a system for controlling a model in a simulator instead of an actual product by a control program operating on another computer such as HIL (Hardware In the Loop) simulation system by dSPACE, Inc., for example. Since this system simulates in real time, objects of the simulation are products having slow response (for example, products that can be simulated at not less than 1 msec simulation time intervals) such as automobiles, ships and the like. Therefore, it is difficult for this system to simulate a product of a relatively small size and having rapid response (for example, a product that should be simulated at each interval of about 100 &mgr;sec) such as a magnetic disk drive (HDD) or the like.
Inventors of the present invention have proposed a support system by which a built-in software (control program) can developed separately from mechanism design without producing a trial product of the mechanism, putting a three-dimensional real-time simulation apparatus in the center. Validation of the control program by this support system is done on the task level. In this support system, an operation of the actuator in response to a command from the control program's side is simulated, and the control program is validated on the basis of an ON/OFF signal of the sensor according to the operation. Therefore, this support system cannot validate (develop, debug) of the control program on the servo level analyzing dynamics of the model.
The servo mechanism is an automatic feed-back control system for mechanical motions, which is used to control a system in which a controlled variable or a control output is a mechanical position [or one of inductive variables (such as velocity, acceleration and the like). To validate a control program for the servo control part, it is necessary to simulate the servo mechanism not on the task level but while dynamically analyzing a controlled variable such as the above mechanical position or the like (that is, on the servo level). When validation is made on the servo level, it is necessary to strictly simulate by dynamic analysis, which leads to difficulty in simulation in real time.
For this, it is desired to be able to develop and debug (validate) the servo control part (hereinafter referred to a servo control program, occasionally) of the control program for a product of a relatively small size and having rapid response without using an actual mechanism.
Meanwhile, there has been a general technique of modeling a controlled object and a control law for the controlled object, and validating the control law. This technique enables validation of the control law on the theoretical level, but cannot cope with various problems (execution speed, code size, consumed memory quantity, mixing of bugs and the like) occurring when the validated control law is coded into actual firmware (control program). Additionally, since this technique is for validation of a control law, this technique cannot validate a control program created on the basis of the control program. When the control program is validated, the above general technique is used after all.
SUMMARY OF THE INVENTION
In the light of the above problems, an object of the present invention is to provide a control program development support apparatus enabling development and debugging (validation) of a control program for controlling a relatively small product (mechanism) having rapid response without using an actual mechanism.
The present invention therefore provides a control program development support apparatus, in which a predetermined simulation cycle in a simulation unit is set shorter than a predetermined control cycle in a control program executing unit, the simulation unit simulates an operation of a mechanism in the predetermined simulation cycle for a time corresponding to the predetermined control cycle, and outputs a state variable of the mechanism to a holding unit, a simulation control unit makes the simulation unit shift to a state of waiting for a response from the control program execution unit and makes the control program execution unit initiate an operation of calculating a controlled variable according to the state variable when the state variable from the simulation unit is held in t
Sato Yuichi
Senta Yosuke
Fujitsu Limited
Thomson William
LandOfFree
Control program development support apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Control program development support apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Control program development support apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3301415