Optimal Design of Parallel Elastic Actuators for Minimizing Required Torque and Power: Comparison with Series Elastic Actuators

This paper proposes an optimal design methodology for Parallel Elastic Actuators (PEAs) that minimizes torque and power consumption for tasks with external conditions. Furthermore, the paper advocates for selecting an actuator based on a comparison of the dynamic characteristics of PEAs and Series Elastic Actuators (SEAs) for a specific task. However, the design of actuators may need to vary depending on the task and application, but the criteria for this are often unclear. To address the ambiguous design criteria, we analyze the dynamic characteristics of PEAs and SEAs under external conditions and utilize them for optimal design. By formulating cost functions for various tasks, we identify the most suitable actuator design for each task. This study establishes criteria for designing PEAs for tasks with external conditions and proposes a general framework for PEA design optimization.