FB_CrashPrevention - General Information

Overview

Type:	Function block
Available as of:	V1.0.0.0

Task

Function block for helping to prevent carrier collision.

Description

A collision prevention function has been implemented for preventing mechanical damage to the system. It stops the carriers before they come too close to each other.

The instance of the function block FB_CrashPrevention must be called cyclically.

If the calculated distance between the carriers is lower than the minimum distance defined by the parameter lrCrashDistance (see ST_CrashPreventionParameter), the complete Lexium™ MC multi carrier transport system is stopped.

The collision prevention is the second layer to help prevent a collision between carriers. It is the backup option if the MoveGapControl command is unsuccessful or if a move command (like for example MoveDirectly or MoveSync) has not been correctly parametrized.

Properties

Name	Data type	Accessing	Description
ifMulticarrier	IF_Multicarrier	Read/Write	Interface to the function block FB_Multicarrier.
stParameter	ST_CrashPreventionParameter	Read/Write	Property for input of the structure ST_CrashPreventionParameter.

Inputs

Input	Data type	Description
i_xEnable	BOOL	A rising edge FALSE -> TRUE activates and initializes the function block, a falling edge TRUE -> FALSE deactivates the function block. A deactivated function block does not execute actions and the outputs are set to the default value.
i_xStart	BOOL	A rising edge of the input starts the function block.

Outputs

Output	Data type	Description
q_xActive	BOOL	Indicates TRUE if the execution of the function block is active. As long as the output is TRUE, the function block must be executed cyclically.
q_xReady	BOOL	Indicates TRUE if the function block is ready and can be controlled through its inputs according to its functionality. After the function block has been enabled with a rising edge of i_xEnable, the output q_xReady is only set to TRUE if the function block can process instructions from the inputs. If invalid input values are detected during initialization, q_xReady remains FALSE. If the function block has detected an error, q_xReady is set to FALSE. If the function block is deactivated using i_xEnable, q_xReady immediately becomes FALSE.
q_xError	BOOL	Indicates TRUE if an error has been detected. For details, refer to q_etResult and q_sResultMsg.
q_etResult	ET_Result	Provides diagnostic and status information as a numeric value. If q_xError = FALSE, q_etResult provides status information. If q_xError = TRUE, q_etResult provides diagnostic/error information.
q_sResultMsg	STRING [255]	Provides additional diagnostic and status information as a text message.