This section contains general information on the motion command structure of Parametric Robot Control. Specific topics are addressed in separate pages:

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In order to define robot programs, PRC utilizes the following categories of components:

Motion Groups

Motion groups serve to structure motion commands and to reduce overhead (e.g. when the tool geometry is individually specified for each motion. A motion group defines the interpolation, tool, and base for all motions contained within. PRC supports the following motion groups:

Point-to-Point (PTP) Motion Group: This motion group may contain either Axis motion commands or Cartesian PTP commands.

Continuous Path (CP) Motion Group: This motion group may contain LINear and CIRcular motion commands

Motions

Motions define a robot motion. In general, a motion consists of a target (Cartesian or Joint) alongside values for the speed (by default m/sec for CP and % for PTP), interpolation, and acceleration. These motion types are currently implemented:

LINear Motion: The target position is defined by a Cartesian Target.

PTP Motion: The target position is defined by a Cartesian Target and a posture.

Axis Motion: The target position is defined by a Joint Target.

CIRC Motion: Three target positions as Cartesian Targets define an arc.

Actions

Actions define a robot action. The action types are currently implemented:

Hold: The robot waits for a timespan defined in seconds.

Insert Code: Inserts a given code into the program. The code is not simulated.

Set Variable: Sets a robot variable to a given value.

Wait for Variable: Waits for a robot variable to be set to a given value.

Flows

Flows allow you to define the data flow of a process. These flow types are currently implemented:

If-Else: Split the dataflow according to a variable that is checked at runtime.

While: Repeat an action while waiting for a variable to reach a given state.

End: End the execution of a program.

Task

The commands above can be grouped within a Task.

Basics

A robot program should ideally start with an axis motion (grouped within a PTP Motion Group) so that the start position is clearly defined. If a motion group does not reference a specific tool or base, either the previous or the default tool/base (as defined in the settings) is selected. The same applies to the programmed speed.

The commands are processed in order. For example: A task contains a PTP Motion Group "Start", followed by a While block that references the variable §IN[1] and the PTP Motion Group "Loop". The While block is followed by the PTP Motion Group "End".

Task "Program"

PTP Motion Group "Start"

While

PTP Motion Group "Loop"

PTP Motion Group "End"

That program would start with "Start" and then repeat "Loop" until $INT[1] is TRUE, then it will process "End" and terminate the program.