A Robotic Torso Joint With Adjustable Linear Spring Mechanism for Natural Dynamic Motions in a Differential-Elastic Arrangement

To be operated in unknown or complex environments, modern robots have to fulfill various challenging criteria. Among them, one finds requirements such as a high level of robustness withstand impacts and the capabilities physically interact safe manner. One way achieve that is integrate variable-stiffness actuators into systems, enabling compliant behavior through elastic components providing additional adaptability impedance. Here, we introduce novel adjustable linear stiffness joint mounted differential-elastic arrangement. The mechanism integrated anthropomorphic upper body DLR David robot responsible for spinal rotation. Consequently, actuator crucial overall workspace realization energy-efficient natural motions dynamic running. proposed hardware setup experimentally validated terms linearity spring characteristics, intrinsic damping, excitation resonance frequencies, ability alter these frequencies adaptation during motions.