RobTranslation

Introduction

RobTranslation is a tool, that allows you to displace

  • test frame
  • an object
  • a list of objects
  • a group of objects

along a Z axis in the parent frame using Denavit-Hartenberg's notation. Object's coordinate frame can be visualized using RobTranslation tool. It's also possible to make an open chain from RobRotation and RobTranslation objects and using this to model behavior of a robot/manipulator. To define a world frame use RobWorld. For more general moving pattern use trajectory tool.

Usage

RobTranslation tool's position inside
an example Animate tool tree.
  1. Install Animate workbench if you haven't done so already.
  2. Open a file in FreeCAD.
  3. Select Animate workbench on the workbench toolbar.
  4. Click on RobTranslation's icon on Animate toolbar or select Robotics > RobTranslation in Animate menu.
  5. Open a Combo View ( View > Panels > Combo View ).
  6. Select RobTranslation tool in a tree view on a Model Tab inside the Combo View.
  7. Go to General properties on a Data Tab inside the Combo View.
  8. Select Animated Objects and choose an object/objects to be displaced.
  9. Go to RobTranslation's properties on a Data Tab inside the Combo View.
  10. Fill all d-h Parameters and Translation properties with floats which have an uniform length.
  11. Double-click the RobTranslation tool in the tree view on a Model Tab inside the Combo View.
  12. A RobTranslation's dialog is opened on a Tasks tab inside the Combo view.
  13. Use a slider in the RobTranslation's dialog to skim through the specified translation range.
  14. Change more properties according to your preferences, their meanings are explained in the next section.

Properties

Property / Property Group Description
Base FreeCAD properties necessary for correct display in the tree view.
Label Name of this RobTranslation tool shown in the tree view.
Group A list of children to be shown in the tree view.
Frame Properties controlling look of a coordinate frame.
Frame Arrowhead Length Height of a cone making frame's arrowhead. Must be in range between 1 and 1e6.
Frame Arrowhead Radius Radius of a cone making frame's arrowhead. Must be in range between .5 and 1e6.
Frame Transparency Frame transparency in percents. Total transparency is 100.
Shaft Length Length of an arrow's shaft. Must be in range between 1 and 1e6.
Shaft Width Width of an arrow's shaft. Must be in range between 1 and 64.
Show Frame Toggle coordinate frame.
Show Frame Arrowheads Toggle coordinate frame's arrowheads.
Show Frame Labels Toggle coordinate frame's axis labels.
General Main properties controlling overall behavior.
Allow Control Allow control to change RobTranslation's time. Not implemented.
Allow Server Allow control to change RobTranslation's parameters. Not implemented.
Animated Objects A list of objects rotated about Z axis in a parent frame.
Interpolate Linearly interpolate rotation values if Time is between specified timestamps.
Object Placement Current placement of Animated Objects within a Parent Frame based on rotation and d-h parameters properties and Time.
Parent Frame Placement Current placement of a parent frame in case of nested RobWorld, RobRotation and RobTranslation tools.
Time Current Time based on which Animated Objects pose is computed from the rotation and DH parameters.
Label Properties specifying how labels look.
Distance To Axis Distance between a label and an arrowhead if it's visible or an arrow shaft.
Font Family Label font family - SERIF, SANS, TYPEWRITER.
Font Size Label font size.
Font Style Label font style - NONE, ITALIC, BOLD, BOLD ITALIC.
Subscription Label subscription - use spaces for horizontal alignment.
Superscription Label superscription - use spaces for horizontal alignment.
d-h Parameters Properties specifying parameters of Denavit-Hartenberg notation.
a DH parameter specifying displacement along X axis.
alpha DH parameter specifying rotation about X axis.
d DH parameter specifying displacement along Z axis.
d Maximum Upper limit of theta range. Must be greater than d Minimum.
d Minimum Lower limit of theta range. Must be less than d Minimum.
d Offset Offset of theta rotation.
theta DH parameter specifying rotation about Z axis.
Translation Properties describing a rotation.
d Sequence A list of floats describing translation along Z axis in given timestamps.
Timestamps A list of floats marking when object reached given rotation.