An integrated engineering approach for the preliminary design and synthesis of delta robots

The design of delta robots poses significant challenges as their mechanical behavior depends on a high number of dimensional parameters and dynamic factors. This is further compounded by the presence of demanding performance requirements, particularly in terms of position accuracy during high-dynamics motion tasks. By leveraging theoretical models, dynamic optimization techniques and advanced simulations, the present paper aims to streamline the design process, providing a structured engineering method and tool to address the dimensional synthesis of delta robots, encompassing kinematics, dynamics, link flexibility, and ball joint clearance. The systematic design process incorporates user requirements, including bounding box specifications, cycles per minute for pick-and-place operations, end-effector accuracy tolerance, maximum static payload, and cost minimization. The methodology involves an initial dynamic optimization phase employing a genetic algorithm to derive optimal dimensional parameters. Analytical models implemented in Matlab expedite the iterative optimization process. Then, the optimized design is virtually prototyped in RecurDyn flexible multibody simulation tool for validation by including the link flexibility and the effect of ball joint clearances. The iterative approach ensures that the final design aligns with user expectations. Additionally, the paper addresses motor selection based on torque requirements and proposes an approach for evaluating the robot performance in terms of maximum end-effector acceleration and payload. Finally, the efficacy of the tool is evaluated through a case study focused on designing a manipulator as an integral part of a collaborative research project with an industrial partner.