Chen Taiji Cloud Hands
For students wishing to practice at home, here some resources to help. In the Chen style Tai Chi movement "Wave Hands like Clouds" (Yun Shou) this uses the double arm silk reeling movement with a side stepping action. The hands and arms rotate and move in a circular pattern and is likened to the weaving motion of a silk worm.
View the following youtube clip from 3.16 minutes to 3.30 minutes for an example of the movement looking from behind.