GUI issue #66: Update documentation for the prismatic- and cylindric

joints, adding a button for switching between the two joint types.
Remove two repeated sentences in the Free joint documentation.

Author: kmokstad

src/ReferenceGuide/htm/properties/_cylindric_joint.htm

@@ -20,19 +20,25 @@ <h5>
 </td></tr></table>
 </h5>
 
-<h1><a name="_properties_cylindric-joint"></a>Cylindric Joint</h1>
-
-<p>The Cylindric joint object is used to represent a Cylindric joint in a FEDEM model.
-A Cylindric joint has four unconstrained DOFs that allow both translational
-displacement along the local z-axis, and rotation about the local z-axis.
+<h1><a name="cylindric-joint"></a>Cylindric Joint</h1>
+
+<p>The Cylindric joint object is used to represent a Cylindric joint in a FEDEM model.</p>
+
+<p>A Cylindric joint consists of a slave triad sliding along a straight path
+defined by two or more master triads. The local coordinate system of the joint
+is defined with its Z-axis directed along the slide path. The X- and Y-axes
+are then defined from the coordinate systems of the master triads.</p>
+
+<p>The Cylindric joint has four unconstrained DOFs that allow for translational
+displacement along the local Z-axis, and rotation about all three axes.
+It has two joint DOFs with property settings. They allow you to control the
+translational displacement of the slave triad relative to the first master triad
+along the local Z-axis (the slider variable), and the
+angle of rotation of the slave triad about the local Z-axis, respectively.
+The rotation angle is measured between the X-axis of the first master triad and
+the X-axis of the slave triad.
 It does not constrain motion in the other two rotational directions.</p>
 
-<p>The Cylindric joint has two joint DOFs. They are the translational distance
-along the local z-axis from the first master to the slave (the slider variable)
-and the angle of rotation of the slave about the local z-axis.
-The rotation angle is measured between the x-axis of the first master triad and
-the x-axis of the slave triad.</p>
-
 <p>See the section on "Joints" in the "Mechanism Elements" chapter in the
 FEDEM User's Guide, for more information on Cylindric joints.</p>
 

src/ReferenceGuide/htm/properties/_cylindric_props.htm

@@ -12,4 +12,9 @@
 determines how fast the slave rotates as it translates along the joint axis.
 See the FEDEM Theory Guide, Section 6.4.3 "Screw joint" for more information
 about the screw ratio.</td></tr>
+<tr><td>Convert to Prismatic joint</td><td>Click this button to replace the
+Cylindric joint with a <a href="#prismatic-joint">Prismatic joint</a> connected
+to the same set of triads. The properties assigned to the <i>Tz</i> DOF will
+then be transferred to the Prismatic joint, whereas the <i>Rz</i> properties
+(if any) will be lost.</td></tr>
 </table></p>

src/ReferenceGuide/htm/properties/_prismatic_joint.htm

@@ -20,25 +20,26 @@ <h5>
 </td></tr></table>
 </h5>
 
-<h1><a name="_properties_prismatic-joint"></a>Prismatic Joint</h1>
+<h1><a name="prismatic-joint"></a>Prismatic Joint</h1>
 
 <p><img src="../../img/prp/prp-prismatic-joint-2.png"></p>
 
-<p>The Prismatic joint object is used to represent a Prismatic joint in a FEDEM model.
+<p>The Prismatic joint object is used to represent a Prismatic joint in a FEDEM model.</p>
 
 <p>A Prismatic joint consists of a slave triad sliding along a straight path
 defined by two or more master triads. The local coordinate system of the joint
-is defined with its z-axis directed along the slide path. The x- and y-axes
-are defined from the coordinate systems of the master triads.
-</p>
+is defined with its Z-axis directed along the slide path. The X- and Y-axes
+are then defined from the coordinate systems of the master triads.</p>
 
 <p>The Prismatic joint has three unconstrained DOFs, but only a single DOF
 (the slider variable, i.e., the distance from the first master to the slave
-triad in the direction of the local z-axis) with property settings that allows
+triad in the direction of the local Z-axis) with property settings that allows
 you to control the translational displacement of the slave triad.
-Rotation is constrained about the z-axis, but not in the other two directions
-(the slave triad can rotate about the local x- and y-axes independently of the
-masters triads).Two prismatic joints can be combined to make a stiff
+Rotation is constrained about the Z-axis, but not in the other two directions
+(the slave triad can rotate about the local X- and Y-axes independently of the
+masters triads).</p>
+
+<p>Two prismatic joints can be combined to make a stiff
 translating connection, by attaching the master triads for the two joints to
 the same FE nodes (in the same order) and attaching the two slave triads to
 the same FE part but on different nodes.</p>

src/ReferenceGuide/htm/properties/_prismatic_props.htm

@@ -6,5 +6,11 @@
   This file is part of FEDEM - https://openfedem.org
 --->
 
-<tr><td>Friction</td><td>Specifies the friction in the Prismatic joint.</td></tr>
+<tr><td>Friction</td><td>Specifies the friction in the <i>Tz</i> DOF
+of the Prismatic joint.</td></tr>
+<tr><td>Convert to Cylindric joint</td><td>Click this button to replace the
+Prismatic joint with a <a href="#cylidric-joint">Cylindric joint</a> connected
+to the same set of triads. The properties assigned to the <i>Tz</i> DOF
+(if any) will then be transferred to the Cylindric joint.</td></tr>
+
 </table></p>