Driving Sketches

EDIT: short question: Can I add bodies to driving sketches?

I’m new to Shapr and probably doing it wrong. I started with creating the 55 gallon barrels with an armature running through the center. These are for sculptures creating human figures out of recycled barrels. My goal is to move the arms and legs into different positions making the poses more natural and to find out what size my inner armature lengths would need to be as well as where to have them intersect the barrels. I’m using my iPad Pro and pencil pro - very new to Shapr3d. I’ve been trying to work with “driving sketches”. I’m trying to articulate these barrel parts like a leg would on a human. Bottom stays locked to horizontal, then a knee joint, when I articulate the top end point (thigh) it would bend the knee like someone is squatting. So I created the barrels with armature first. Then I drew the driving sketch on the offset construction plane. Tested it by holding and moving top end point - it moved like a leg/knee. I projected those lines onto my armature of the Barrel set up. Went back to move the end point on the construction plane - it moved but the barrels did not. How can I make this work? I’ve been using ChatGPT and it is giving me all kinds of wrong answers.