ABB

Cartesian trajectories for ABB robots (IRC5 controllers)

Vendor specifics
Teach pendant FlexPendant
Programming / simulation software RobotStudio
Software FlexPendant SDK, Microsoft CE + Visual Studio
Programming language RAPID
Relevant hardware Robots of the IRC5 controller
Further reading

Trajectory composition

Programming is done with move instructions (motion types) that move the robot to specified targets.

  • Linear Cartesian motions
    MoveL
    • Move linearly to a specified target.
    • Possible arguments: target point, speed, coordinate system, duration until point (replaces speed), and others
  • Circular motions
    MoveC
    • Build circular, open motion arcs, using a via-point and end point.
    • Possible arguments: point on circle, target point, coordinate systems, duration, and others
  • Joint space interpolation
    MoveJ
    • Move the robot to specified points using joint interpolation. All joints will reach their destination at the same time.
    • Possible arguments: Target point, speed, zone, tool, and others. The tool center point is the point moved to the destination.

Waypoint representation

Individually taught points (type robtarget) have the following field representation:

trans
rot
robconf
extax

Individual fields

  • trans: x, y, z (position of tcp)

  • rot: q1, q2, q3, q4 (orientation in quaternion notation)

  • robconf: cf1, cf4, cf6, cfx (axis configuration of the robot for possibly ambiguous axes). Each field (integer) indicates the configuration quadrant for the numbered axis and is counted in positive or negative quarter revolutions of 90° starting from zero:

    ...
-3 = axis is in (-270°, -180°)
-2 = axis is in (-180°, -90°)
-1 = axis is in (-90°, -0°)
 0 = axis is in (+0°, +90°)
 1 = axis is in (+90°, +180°)
 2 = axis is in (+180°, +270°)
...

  • extax: [eax_a, eax_b, eax_c, eax_d, eax_e, eax_f] (list of up to six external hardware axes)

Different coordinate systems for point representations are possible, such as world or various object coordinate systems.

Trajectory parameterization and execution

Specification of velocity

  • In form of a speed argument to move instructions during teaching of fly-by points. The speed is valid until the next point
  • Path segment specific with VelSet (overrides global velocity settings until reset). Can be either specified as percentage of the current global velocity or can be set to become the new max velocity.
  • Global adjustments with motsetdata, affects all points

Specification of acceleration

  • Path segment specific accelerations with AccSet (overrides global acceleration until reset). Provokes slower acceleration and deceleration (percentage) of the global settings.
  • Global adjustments with motsetdata, affects all points. This also includes adjustment of ramping accelerations etc.

Blending

  • Taught positions can either be fly-by points, or stop points
  • During MoveL, fly-by points are automatically blended, leading to adjusted corner paths (parabolas). Stop points are exactly passed.
  • The blending configuration is handled with zone data that specifies how corner paths are realized.
  • A parameterization of different zones allows to design corner paths in which tool orientation and Cartesian position can be started and stopped Individually.

Parallel IO operations

  • MoveLDO: Move linearly and trigger an I/O operation at the target’s middle corner path
  • MoveCDO: Move in a circle and trigger an I/O operation at the target’s middle corner path

Online (real-time) trajectory modifications

  • Offsets to paths can be realized with CorrWrite and special correction generators. No information on real-time capability found.