I worked at Microsoft's Studio Soho for a little under a year bringing the first season of Sesame Street Kinect to life. I joined the team very early in the pre-production phase and my initial tasks were focused on developing a pipeline to support the main character of the show - Cooper - a digital version of the physical puppets synonymous with the show. This pipeline included a quite advanced rig for Cooper that would deform in a believable manner, mimicking the range and style of motion of his physical counterparts. The rig had to have the capacity to be hand animated and also mo-cap friendly as the majority of Cooper's animation data was to be realised by motion capturing a life-size physical puppet that the team at Sesame Street manufactured especially for us. I also had to build a data pipeline from the ground up, leveraging 3rd party model and animation formats licensed by the studio. This pipeline was eventually handed on to Vladimir Yudin to develop further for Season 2.
The following video shows an early motion capture test we did with a near final version of the rig. We flew over to New York for 2 days and captured this performance using the mighty Kevin Clash (Elmo) who voiced and operated Cooper. The video has no audio as it was strictly a motion performance test and is pulled from the calibration phase. I does show how well the rig behaves when being driven in this manner. The main performance begins around 30 seconds in.