# Robot start and execution control

The start of execution of the robot is performed according to the parameters and criteria set by the robot manufacturer, as well as the controller that is integrated into the project. These aspects condition the stop or pause of the running program, and the restart of the execution sequence.

# Manual/automatic program selection

Once the robot has started running, it is necessary to select which program to run, either the manual or the automatic program according to certain bits transmitted by the PLC.

This selection will depend on the type of program management integrated in the robot at the start of the sequence. As a general rule, 2 forms of management are envisaged:

• By initial single program. In this case, each execution start will go through a single program, and it will be in this one where the decision of whether to run the manual or automatic program is taken (e.g. Kuka's Cell program).

• Specific program selection. This mode allows the PLC to directly start the manual or automatic program (e.g. Fanuc PNS system).

# Manual program

The manual mode program allows the user, through the PLC, to send the robot to the coordinates of home (Go to home) or maintenance area (Go to maintenance area) defined in the software. When the robot reaches the requested position, it will be indicated to the PLC (In Home / In Maintenance). As well as moving through the HMI interface of the PLC the robot.

# Automatic program (Starter) and run cycle control

When starting the Starter program the robot will move to the Home coordinates. Once this point is reached, the PLC is notified by the In Home signal. From this point on, the program will be controlled by the interaction of PLC signals.

The automatic program is divided into 2 sections. The first section manages the data associated with the selected recipe and its layer (Layer) or movement (Pick) to be performed. And a second section in charge of managing the movement sequence associated with the type of gripper, the selected mapping area and the data loaded during the data loading.

The execution of this program is cyclic so that each time a data load and/or a transaction sequence occurs, it returns to the data load section to update the information of the next transaction.

The data loading process is conditioned by the Load Data signal. If this signal is active (true), the data loading process starts, this is in turn divided into 2 sections, the first one dedicated to the PLC to reset internal values of the robot memory, and a second section with the data loading of the selected recipe, being able at this point to force the loading of the information of a specific layer and / or pick. Once the data loading is finished, a pulse of the Data Loaded signal is emitted. Then, if the Cell enable (Global) signal is deactivated, the program waits for the Load Data signal to be deactivated. When this happens, it returns to the starting point of the data loading sequence.

If the Cell enable (Global) signal is active, the motion sequence associated with the selected recipe is executed.

By controlling the Load Data, Cell enable (Global) signals, and the zone assignment of each selected recipe, it is possible to control the management of multiple palletizing stations linked to the same robot simultaneously. This control logic is conditioned to the morphology of the palletizing cell and the methodology for its integration with the rest of the elements of the installation.

# Data clearing

At this stage of the program, the PLC is allowed to reset internal values of the robot's memory, such as the height at which the robot is palletizing at each station/zone, among other data.

During the data loading process, the Clear Data signal of the desired station/zone must be activated. Once the information has been cleared, a pulse is received as confirmation via the associated Data Cleared signal.

# Data loading sequence

Depending on the selected recipe, the program that stores all the information associated with the recipe and mosaic will be started. Once started, it will check if the layer and pick data are valid, and if so, it will store in memory the coordinates of the required palletizing sequence and other data such as the number of products required and whether they are rotated or not, among others.

If the recipe is 0, the robot can be sent to Home, using the Go to home signal.

# Forced layer and/or pick

To edit the layer and pick values, before loading the data, the Force Counters signal corresponding to the active recipe zone must be activated. Once the counter update is completed and the data is loaded into memory, a pulse of the Data Loaded signal is received. Once this pulse is received, the Force Counters signal is deactivated.

# Execution of palletizing sequences

After the data loading process, if the Cell enable (Global) signal is active, the palletizing sequence is started.

Depending on the type of gripper selected, it presents a different type of standard palletizing sequence. By default, 4 different programs are provided for each palletizing sequence, as the mapping integrates 4 different zones (Pick-Pack). Each of these programs uses different memory addresses, depending on each zone.

When selecting a recipe, during the data loading process, it is registered internally which of these programs will be executed. This value was defined by the zone value in the palletizing station node.