MC_GearIn

 Function Block - Performs a slave axis move which follows the master axis based on the ratio specified by RatioNumerator and RatioDenominator.

Inputs

Input	Data Type	Range	Unit	Default	Description
Execute	BOOL	FALSE, TRUE	N/A	No default	On the rising edge, request to queue the slave gear ratio move.
Master	AXIS_REF	1 to 256	N/A	No default	Name of a declared instance of the AXIS_REF library function. See Axis Name and Number. See AXIS_REF Structure.
Slave	AXIS_REF	1 to 256	N/A	No default	AXIS_REF.AXIS_NUM is the slave axis number. See AXIS_REF Structure.
RatioNumerator	DINT	-2147483648 to 2147483647	N/A	No default	Numerator of master/slave ratio.
RatioDenominator	DINT	-2147483648 to 2147483647	N/A	No default	Denominator of master/slave ratio.
Acceleration	LREAL	No range	User unit/sec2	No default	Trapezoidal: Acceleration rate. S-curve: Maximum acceleration. See S-curve and Trapezoidal Acceleration / Deceleration.
Deceleration	LREAL	No range	User unit/sec2	No default	Trapezoidal: Deceleration rate. S-curve: Unused. See S-curve and Trapezoidal Acceleration / Deceleration.
Jerk	LREAL	No range	User unit/sec3	No default	Trapezoidal: 0 (zero). S-curve: Constant jerk. See S-curve and Trapezoidal Acceleration / Deceleration.
BufferMode	SINT	0 to 1	N/A	No default	0 = Abort. 1 = Buffer. See Buffer Modes.

Outputs

Output	Data Type	Range	Unit	Description
InGear	BOOL	FALSE, TRUE	N/A	Indicated the slave axis is locked on to the master axis.
Busy	BOOL	FALSE, TRUE	N/A	High from the moment the Execute input goes high until the time the move is ended.
Active	BOOL	FALSE, TRUE	N/A	Indicates this move is the Active move.
CommandAborted	BOOL	FALSE, TRUE	N/A	Indicates the move was aborted.
Error	BOOL	FALSE, TRUE	N/A	Indicates either: An invalid input was specified. The move was terminated due to an error.
ErrorID	INT	No range	N/A	Indicates the error if the Error output is set to TRUE. See PLCopen Function Block ErrorIDs.

Remarks

SlaveCommandPosition = MasterActualPosition * RatioNumerator / RatioDenominator

• 
  
• This function block starts a motion-related action and stores data for calculations and error checking.
  If using a dual-core controller, see Call Function Blocks Multiple Times in the Same Cycle.

• See Function Blocks - General Rules about how inputs and outputs work.
• When this command is executed, the slave axis accelerates or decelerates (using the Acceleration, Deceleration, and Jerk) to the target velocity determined by the master axis velocity and the ratio.
• When the slave axis reaches a velocity within the In Gear bandwidth around the target velocity, it locks on to the master, and the InGear output goes high.
  • See Axis Parameters.
• When the slave is locked to the master, the slave motion is no longer affected by the acceleration, deceleration, and jerk inputs.
  • Example: If the In Gear bandwidth is set to 0.1 User unit/sec, the InGear output turns on if the slave velocity is within +/- 0.1 User unit/sec of the target velocity.
  • The slave axis continues to follow the master axis until this move is aborted.
• See Main about how this function is used in the Hole punch project.

Aborting Gearing

Gearing functions can generate large accelerations while following the master.

• If the aborting function block has small, non-zero Jerk, or small acceleration values, it can take a long time for an accelerating axis to reach the target velocity, or position of the aborting function block.
  • If the Jerk and/or acceleration of the aborting function cannot be increased to suitable values, it may be desirable to either:
    • Abort the gearing function with an MC_GearOut with higher accelerations and/or Jerk values (or zero jerk value).
    • Execute the next MC motion function block (e.g., MC_Halt).

Time to Reach the Target Velocity

While following the master, gearing functions can generate large accelerations.

• If the gearing function is aborted while the axis is currently accelerating, and the aborting function block has small non-zero Jerk or small acceleration values, it can take a long time to reach the target velocity, or position of the aborting function block.
  • If the Jerk and/or acceleration of the aborting function cannot be increased to suitable values, it may be desirable to either:
    • Abort the gearing function with an MC_GearOut with higher accelerations and/or Jerk values (or zero jerk value).
    • Execute the next MC motion function block (e.g., MC_Halt).

Figure 1: MC_GearIn

Time Diagram

Figure 2: Time Diagram

FBD Language Example

Not available.

FFLD Language Example

IL Language Example

Not available.

ST Language Example

(* MC_GearIn ST example *)
   Inst_MC_GearIn( GearInReq, Axis1, Axis2, 2, 1, 150.0, 150.0, 0, 0 );
//Inst_MC_GearIn is an instance of MC_GearIn