Flexure Mechanisms with Variable Stiffness and Damping Using Layer Jamming Flexures provide precise motion control without friction or wear. Variable impedance mechanisms enable adaptable and robust interactions with the environment. This paper combines the advantages of both approaches through layer jamming. Thin sheets of complaint material are encased in an airtight envelope, and when connected to a vacuum, the bending stiffness and damping increase dramatically. Using layer jamming structures as flexure elements leads to mechanical systems that can actively vary stiffness and damping. This results in flexure mechanisms with the versatility to transition between degrees of freedom and degrees of constraint and to tune impact response. This approach is used to create a 2DOF, jammingbased, tunable impedance robotic wrist that enables passive hybrid forceposition control for contact tasks. Keywords: Compliant JointMechanism, Compliance and Impedance Control, Mechanism Design

Design of LowProfile Compliant Transmission Mechanisms Robotic origami design allows creating mesoscale robotic systems and mechanisms not limited by degrees of freedom, miniaturization and assembly downsides of conventional transmission mechanisms. However, unlike the traditional rigid approaches, robotic origami application has been limited by the complex deformation and kinematics of the compliant joints and actuation based on active materials or conventional electric motors. To generalize their application at mesoscale requires a combination of the predictability of traditional rigid kinematics and the manufacturing flexibility of robotic origami. Here we present a study of conventional transmission mechanisms, including a slidercrank and camfollower, made in quasi2D form by selective machining and stacking of multiple layers of composite material with minimal assembly. Owing to a compliant design powered by lowprofile piezoelectric motors, our 5.3 mm thick and lightweight mechanisms transmit rotational motion to translational movements in and outofplane. We develop analytic models that we validate in terms of force and motion output on our prototypes.