Fig.5.4.1 Station 2
As an example of "realistic" implementation of Machine Tools, we employed a panel type PC of IBM, which is specially designed for the industirial use. It has a 50MHz DX2 as CPU, a "Touch Panel" interface promising a good user interface, and 2 PCMCIA slots for future expansions. (This time we used a PCMCIA network card.) At the same time, this panel pc is combined with an expansion unit. This expansion unit offers additional 3 ISA slots, MELDAS MAGIC is located at one of the slots. The figure of operation panel with the panel type computer is showed below.
The machining data file(FADL) which is generated by CAM station is transferred to station2, and is interpreted at FADL interpreter and it's library, and finally is handed to servo system as positioning command.
As a result of the process, this station2 was driven two kind of servo unit. One is an exclusive servo with remaked MELDAS MAGIC. This is connected by high speed serial communication network between CNC unit and servo drives, and is main connection form of the present. And the other is general servo system of pulse input driving. To show that the movement of servo motor is following the FADL, an application of displaying of trajectory is added.
The PLC, which is one of important units in machine controller, was used in some part of this system. MELDAS MAGIC board include PLC, so it was used to operate this board normally. In future next step, it will be need to include the PLC which is suitable for OPEN NC. The main hardware of Station2 are described in below.
| PC | |
| IBM-7344/TD> | 486DX2 , 50MHz HDD:500MB RAM:16MB |
| axis drive system | |
| exclusive servo |
drive: MDS-A typeョ (Mitsubisi) - 3 set motor: HA typeョ (Mitsubisi) - 3 set |
| general servo | board:ATPG-45ョ (Cosmo System) drive:MR-J typeョ (Mitsubisi) - 3 set motor:HA-SE typeョ (Mitsubisi) - 3 set |
| DI/DO | |
|
remote I/O (UNI-WIRE SYSTEMョ) |
board: AT-UWョ (Yoshida Electric) DI: IT-8Sョ (Yoshida Electric) DO: IT-8Pョ (Yoshida Electric) |
The demonstration model which is made up in this way enough satisfied above two targets. With FADL and it's library, the necessary and enough function is made up by machine builder. It is easy to correct and to add functions. So it was proved that the architecture of this model meets a independent of function and an addition of new function. As an example of this, we added an application of evasion of interference. This shows that if tool path will interfere with jig, FADL library generates the path that not interfere. This application is not perfect, but is the most suitable for modularity of function and usefulness of FADL and it's library. Still more we added video capture function with the goods of PC's shop. Of course we got at low price. The base of hardware is PC, so to add with a PC's application in this model is much easier than in usual exclusive CNC unit. This means that the development and design costs of machine builder about addition of these functions is particularly low. As a result of this, user will get these functions at low price.