[Glue!] Input / Output


The read-outs of various sensors, which are required to test starting conditions for each application processes, and also to analyze the status of the work-cell, are nice to be kept within the Glue Logic. Preparing such names in the Glue Logic, not only the application processes can use any kind of sensor read-outs by referring their status indicator object names, but also the starting condition of the application processes are automatically checked by the Glue Logic.

In order to reflect the status of the input signal port in the work-cell to the status indicator in the Glue Logic, some system support processes should be prepared especially for this purpose. Such process accepts interruptions from the input signal ports or scans all of them periodically, and updates the sensor status indicators. In some cases, some statistical operations are required in these support processes. Keeping some most recent sampled values as the history of the sensing data, and taking a moving average value as noise free data are some of most general operations among such operations.

On the other hand, in order to control the output signal ports equipped in the work-cell by updating the values of output control names in the Glue Logic, other system support processes should be prepared. Those processes use the data change notification feature for the output control names, and guarantee that the assignment to such output control names are reflected to the status to the output ports of the work-cell, in certain short time period. These support processes can do much more than data passing from the output control names to the output ports. For example, the robot control support process can accept the motion command with the world coordinate system, and convert it to the local coordinate system, or to the joint coordinate system if required. This is the most simple way to implement the abstracted manufacturing devices.

With these two kinds of system support processes, the application processes can access devices attached to the work-cell through the Glue Logic, instead of touching the devices directly.

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