Hi Patrick, thank you for replying to these messages. Since your last message I have bought 2 different Collada animated drone (quadcopter) models from two of the big 3D model markets, turbosquid and CGTrader but have not been successful in converting them correctly to glTF with http://cesiumjs.org/convertmodel.html.
The CGTrader model was advertised with Collada as an available format. With this .DAE, the converter runs and produces a gltf but all the animated parts (the propellers etc) are missing when I use the model in Cesium using the exact same code as the Cesium_Air sandcastle sample.
TurboSquid did a tech support conversion to Collada for me of their model. When I use this model, there is nothing showing in the viewing area of the converter and when I try to use the glTF in cesium I get errors from the cesium renderer and all rendering stops.
I really need a working animated model and after spending $$$ and late nights on this, I am no closer to success.
Have you any advice on how to investigate the conversion issues I am having? The CGTrader model seems my best bet since at least the body of the model renders (with textures) but I am clueless as to how to investigate further.