Robot Workbench

The robot workbench is tool to simulate industrial grade 6-Axis robots, like e.g. Kuka. Following features are planed and partial already implemented:

• Visual representation of 6-Axis Robot (done)
• Forward and inverse kinematic calculation of arbitrary robots (done)
• RobotLib, dynamic readably robot types (work in progress)
• Trajectory simulation (work in progress)
  • collision simulation
  • detection of configuration changes and singularities
  • time estimation
  • used volume (planed)
• Post processor for Kuka robots (work in progress)
• Process and work cell control (planed)
• Movie making out of simulation (planed)

Scripting

This section is generated out of: http://free-cad.svn.sourceforge.net/viewvc/free-cad/trunk/src/Mod/Robot/RobotExample.py?view=markup You can use this file directly if you whant.

Example hwo to use the basic robot class Robot6Axis which represent a 6-Axis industrial robot. The Robot Module is dependend on Part but nor on other Modules. It works mostly with the basic types Placement, Vector and Matrix. So we need only:

from Robot import *
from Part import *
from FreeCAD import *

Basic robot stuff

create the robot. If you not specify a other kinematic it becomes a Puma 560

rob = Robot6Axis()
print rob

accessing the axis and the Tcp. Axis go from 1-6 and are in degrees:

Start = rob.Tcp
print Start
print rob.Axis1

move the first Axis of the robot:

rob.Axis1 = 5.0

the Tcp has changed (forward kinematic)

print rob.Tcp

move the robot back to start position (reverse kinematic):

rob.Tcp = Start
print rob.Axis1

the same with axis 2:

rob.Axis2 = 5.0
print rob.Tcp
rob.Tcp = Start
print rob.Axis2

Waypoints:

w = Waypoint(Placement(),name="Pt",type="LIN")
print w.Name,w.Type,w.Pos,w.Cont,w.Velocity,w.Base,w.Tool

generate more. The Trajectory find allways outomatically a unique name for the waypoints

l = [w]
for i in range(5):
  l.append(Waypoint(Placement(Vector(0,0,i*100),Vector(1,0,0),0),"LIN","Pt"))

create a trajectory

t = Trajectory(l)
print t
for i in range(7):
  t.insertWaypoints(Waypoint(Placement(Vector(0,0,i*100+500),Vector(1,0,0),0),"LIN","Pt"))

see a list of all waypoints:

print t.Waypoints

del rob,Start,t,l,w

working with the document

Working with the robot document objects: first creat a robot in the active document

if(App.activeDocument() == None):App.newDocument()

App.activeDocument().addObject("Robot::RobotObject","Robot")

Define the visual representation and the kinematic definition (see 6-Axis Robot for details about that)

App.activeDocument().Robot.RobotVrmlFile = App.getResourceDir()+"Mod/Robot/Lib/Kuka/kr500_1.wrl"
App.activeDocument().Robot.RobotKinematicFile = App.getResourceDir()+"Mod/Robot/Lib/Kuka/kr500_1.csv"

start positon of the Axis (only that which differ from 0)

App.activeDocument().Robot.Axis2 = -90
App.activeDocument().Robot.Axis3 = 90

retrive the Tcp position

pos = FreeCAD.getDocument("Unnamed").getObject("Robot").Tcp

move the robot

pos.move(App.Vector(-10,0,0))
FreeCAD.getDocument("Unnamed").getObject("Robot").Tcp = pos

create an empty Trajectory object in the active document

App.activeDocument().addObject("Robot::TrajectoryObject","Trajectory")

get the Trajectory

t = App.activeDocument().Trajectory.Trajectory

add the actual TCP position of the robot to the trajectory

StartTcp = App.activeDocument().Robot.Tcp
t.insertWaypoints(StartTcp)
App.activeDocument().Trajectory.Trajectory = t
print App.activeDocument().Trajectory.Trajectory

insert some more Waypoints and the start point at the end again:

for i in range(7):
  t.insertWaypoints(Waypoint(Placement(Vector(0,1000,i*100+500),Vector(1,0,0),i),"LIN","Pt"))

t.insertWaypoints(StartTcp) # end point of the trajectory
App.activeDocument().Trajectory.Trajectory = t
print App.activeDocument().Trajectory.Trajectory

Simulation

To be done..... ;-)

Exporting the trajectory

the Trajectory is exported by python. That means for every Control Cabinet type is a Post processor python module. Here is in detail the Kuka Postprocessor descriped

from KukaExporter import ExportCompactSub

ExportCompactSub(App.activeDocument().Robot,App.activeDocument().Trajectory,'D:/Temp/TestOut.src')

and thats kind of how its done:

for w in App.activeDocument().Trajectory.Trajectory.Waypoints:
	(A,B,C) = (w.Pos.Rotation.toEuler())
	print ("LIN {X %.3f,Y %.3f,Z %.3f,A %.3f,B %.3f,C %.3f} ; %s"%(w.Pos.Base.x,w.Pos.Base.y,w.Pos.Base.z,A,B,C,w.Name))