I am doing the exercises in RoadMaps 6 on the construction of pendulum model. I strictly followed the model structure and its accompanying equations. However, I am not getting the expected results. Instead of an oscillating behavior, Ive got a straight line. Maybe something could be wrong on plotting the results or perhaps there might be a need to change the RunSpecs. I attached the file, hoping that someone would help me track the possible error.
Any help will be greatly appreciated. Thank you very much.