Lecture 4: Infinitesimal rigidity, tensegrities, stresses, duality, Maxwell-Cremona theorem, locked linkages, carpenter's rule theorem
Page 4: Locked linkages: definition of locked, summary of universality results, Carpenter's rule theorem, proof sketch
You can view the paper proving the Carpenter's rule theorem.
These are rough, personal lecture notes handwritten by Erik Demaine used during lecture. Their primary purpose is for reading/review by students of the class.