Remote handling for the DTT divertor: From requirements elicitation to kinematic verification of the Central Cassette End-Effector

The Remote Handling (RH) system of the Italian Divertor Tokamak Test (DTT) facility is undergoing significant advancements, particularly in the design of the Cassette Multifunctional Mover (CMM), the robot devoted at handling both the lateral and central divertor cassettes. This paper presents the design of the Central Cassette End-Effector (CCEE), the RH equipment that will be mounted on the CMM to perform RH operations for the central cassettes. A black box analysis was performed to define the RH operation procedure and elicit a preliminary set of functional requirements. From this set of requirements, tight space constraints due to the port geometry emerged, and also additional actuations of the end-effector were needed to preload the cassette body without stressing the CMM structure. Thus, the V-Model with the Requirement, Functional, Logical, Physical (RFLP) approach in MAGIC Systems of Systems Architect, provided by Dassault Systèmes, was adopted to develop the design from the requirement elicitation to the architecture definition. The defined logical architecture was traced to the physical model in CATIA V6 within the 3DExperience platform. Finally, to verify the fulfillment of the space constraints and the proper functions of the robot actuations in the proposed procedure, a kinematic analysis of the CMM and the CCEE assembly was performed. The results demonstrated the feasibility of the procedure to be validated during the assembly phase planned in 2026 in the DTT Remote Handling Test and Training facility (REMHAT) under construction in Naples, Italy.