id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
1157	[MultiBody] Validating a model with Cylindrical joint returns errors but is built successfully (from MathCore)	Karin Gustafsson	Karin Gustafsson	"The following model returns errors when validating. Similar errors is returned when building. However, the model seems to work as expected.
{{{
model Cylindrical
  annotation(Diagram(coordinateSystem(extent={{-100.0,-100.0},{100.0,100.0}}, preserveAspectRatio=true, initialScale=0.1, grid={10,10})));
  MultiBody.Joints.Cylindrical cylindrical1 annotation(Placement(visible=true, transformation(origin={-20.0,-10.0}, extent={{-10.0,-10.0},{10.0,10.0}}, rotation=0)));
  MultiBody.Parts.InertialSystem inertialSystem1 annotation(Placement(visible=true, transformation(origin={-60.0,-10.0}, extent={{-10.0,-10.0},{10.0,10.0}}, rotation=0)));
  MultiBody.Parts.CylinderBody cylinderBody1(r={1,0,0}) annotation(Placement(visible=true, transformation(origin={20.0,-10.0}, extent={{-10.0,-10.0},{10.0,10.0}}, rotation=0)));
equation 
  connect(cylindrical1.frame_a,inertialSystem1.frame_b) annotation(Line(visible=true, origin={-40.0,-10.0}, points={{9.5,0.0},{-9.5,0.0}}));
  connect(cylinderBody1.frame_a,cylindrical1.frame_b) annotation(Line(visible=true, origin={0.0,-10.0}, points={{9.5,0.0},{-9.5,0.0}}));
end Cylindrical;
}}}

The same happens if you replace the Cylindrical joint with !Planar or a !Universal joint. It seems that changing prefix to constant instead of parameter for startValueFixed will solve the problem but then this value cannot be changed easily in the model. Same thing seems to happen with revolute joint. See for example MultiBody?.Examples.Loops.Engine2."	defect	closed	critical	Red October			worksforme		Karin Gustafsson