Body motion under multi-moving reference frames

David070 · June 22, 2021, 02:08

Hi everyone,

From the UDF manual, we know that through using the macro DEFINE_ZONE_MOTION, we can define a moving body that can rotate about a moving point, but it is still not convenient to simulate a moving body that is under multi-superposed motion since we need to update the rotation axises every timestep. So can we define multi-reference frames in this macro or other one? For example, there are a globe frame and a moving frame (frame1) that is superposed by the globe frame, and a second moving frame (frame2) that is superposed by frame1. And finally, we define a reference motion relative to frame2. How can we realize that? Any advice is appreciated. Thank you very much!

David

David070 · June 22, 2021, 11:24

For example, there is a panel rotate about the z1 axis of a reference frame (frame x1y1z1), meanwhile, the frame x1y1z1 also has translation and rotation relative to the XYZ global frame as shown in the following figure.

June 22, 2021, 02:08	Body motion under multi-moving reference frames	#1
David070 New Member Join Date: Jun 2021 Posts: 13 Rep Power: 5	Hi everyone, From the UDF manual, we know that through using the macro DEFINE_ZONE_MOTION, we can define a moving body that can rotate about a moving point, but it is still not convenient to simulate a moving body that is under multi-superposed motion since we need to update the rotation axises every timestep. So can we define multi-reference frames in this macro or other one? For example, there are a globe frame and a moving frame (frame1) that is superposed by the globe frame, and a second moving frame (frame2) that is superposed by frame1. And finally, we define a reference motion relative to frame2. How can we realize that? Any advice is appreciated. Thank you very much! David

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June 22, 2021, 11:24		#2
David070 New Member Join Date: Jun 2021 Posts: 13 Rep Power: 5	For example, there is a panel rotate about the z1 axis of a reference frame (frame x1y1z1), meanwhile, the frame x1y1z1 also has translation and rotation relative to the XYZ global frame as shown in the following figure.