MC_GearIn

PLCopen motion icon

Function Block A function block groups an algorithm and a set of private data. It has inputs and outputs. - 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 The transition of a digital signal from low to high. AKA: positive edge., request to queue the slave gear ratio move.
Master	AXIS_REF	1, 256	N/A	No default	Name of a declared instance of the AXIS_REF library function A function calculates a result according to the current value of its inputs. A function has no internal data and is not linked to declared instances.. See Axis Name and Number. See AXIS_REF Structure.
Slave	AXIS_REF	1, 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 A change in velocity over time. Because velocity is a vector, it can change in two ways: a change in magnitude and/or a change in direction. In one dimension, acceleration is the rate at which something speeds up or slows down. However, more generally, acceleration is a vector quantity expressing the change with time of the velocity both in magnitude and in direction. See these Wikipedia articles for more information: http://en.wikipedia.org/wiki/Velocity http://en.wikipedia.org/wiki/Euclidean_vector http://en.wikipedia.org/wiki/Rate_(mathematics)	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 In physics, jerk is the rate of change of acceleration. More precisely, the derivative of acceleration with respect to time.	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, 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.
See Call Function Blocks Multiple Times in the Same Cycle if using a dual-core controller.

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 For a group of axes this means: In ACS the velocities of the different axes. In MCS and PCS it provides the velocity of the TCP determined by the master axis velocity and the ratio.
When the slave axis reaches a velocity within the In Gear bandwidth In computer networking, bandwidth refers to a data rate measured in bits per second (e.g., network throughput). The reason for the connection of data rate with the term bandwidth is that the limit to the data rate of a physical communication link is related to its bandwidth in hertz. In a servos system, the frequency at which the small signal response begins to drop off. Stage performance is enhanced by increasing the servo bandwidth. Structural resonances typically limit the achievable 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 Position means a point in space which is described by different coordinates. Depending on the used system and transformation it can consist of a maximum of six dimensions (coordinates).This means three Cartesian coordinates in space and coordinates for the orientation. In ACS there can be even more than six coordinates. If the same position is described in different coordinate systems the values of the coordinates are different. 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