MC_MoveAdditive

PLCopen motion icon

Function Block A function block groups an algorithm and a set of private data. It has inputs and outputs. - Performs a single-axis move for a specified distance from the endpoint of the previous move.

Inputs

Input	Data Type	Range	Unit	Default	Description
Execute	BOOL	0, 1	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 move.
Axis	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 Modify PLCopen Axis for more information. See AXIS_REF Structure.
Distance	REAL	No range	User units	No default	Distance to add to the endpoint of the previous move.
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	LREAL	No range	User unit/sec	No default	Velocity setpoint The target value that an automatic control system (e.g., PID controller) aims to reach..
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, 5	N/A	No default	0 = Abort. 1 = Buffer. 2 = Blend A way that consecutive function blocks cooperate in the transition from the first to the next. to active. 3 = Blend to next. 4 = Blend to low velocity. 5 = Blend to high velocity. See Buffer Modes.

Outputs

Output	Data Type	Range	Unit	Description
Done	BOOL	No range	N/A	Indicates the move completed successfully. The Command 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. has reached the endpoint.
Busy	BOOL	No range	N/A	High from the moment the Execute input goes high until the time the move is ended.
Active	BOOL	No range	N/A	Indicates this move is the Active move.
CommandAborted	BOOL	No range	N/A	Indicates the move was aborted.
Error	BOOL	No range	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 Error output is TRUE. See PLCopen Function Block ErrorIDs.

Remarks

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.
It is typically used with Abort specified at the BufferMode input.
- If BufferMode is not Abort, this move is identical to an MC_MoveRelative.

Figure 1: MC_MoveAdditive

Time Diagram

These images show two examples of the combination of two Function Blocks (FBs) while the axis is in Discrete Motion state:

The left part of the diagram illustrates when the second FB is called after the first one.
- If the first reaches the commanded distance 6000, and the velocity is 0 (zero), the output Done causes the second FB to move to the distance 10000.
The right part of the diagram illustrates when the second move FB starts the execution while the first FB is still executing.
- The first motion is interrupted An asynchronous signal from hardware indicating the need for attention or a synchronous event in software indicating the need for a change in execution. and aborted by the Test signal during the constant velocity of the first FB.
- The second FB:
  - Adds on the previous commanded position of 6000 the distance 4000.
  - Moves the axis to the resulting position of 10000.

Figure 2: Time Diagrams: First and Second FBs

Figure 3: Time Diagram

FBD Language Example

Not available.

FFLD Language Example

IL Language Example

Not available.

ST Language Example

      (* MC_MoveAdditive ST example *) 
      
Inst_MC_MoveAdditive( MovAddReq, Axis1, 123.456, 100.0, 100.0, 100.0, 0, 0 ); 
   //Inst_MC_MoveAdditive is an instance of MC_MoveAdditive function block
MovAddDone := Inst_MC_MoveAdditive.Done;  
   //store Done output into user defined variable