Dynamic modeling and dimensional optimization of legged mechanisms for construction robots

Construction robots are hindered by high energy consumption, limited payload capacity, high costs, and poor terrain adaptability—critical bottlenecks that severely restrict their deployment in complex construction environments. To holistically address these critical bottlenecks, this study introduces legged robotics into construction scenarios and proposes an optimization framework to simultaneously achieve high payload capacity, low energy consumption, and enhanced mobility. First, a bio-inspired leg design is proposed. Second, a novel structural optimization methodology is developed through the integration of dynamic modeling with trajectory planning. Building upon this foundation, a multi-objective optimization of structural dimensions is formulated to address the unique requirements of construction robots. The optimization comprehensively targets the minimization of joint peak torque and energy consumption by optimizing leg segment geometry, while explicitly incorporating constraints including maximum foothold reach, obstacle-clearance requirements, and link stiffness. Results show that the optimized design reduces both joint peak torque and energy consumption by over 20%. Finally, dynamic simulations using ADAMS demonstrate a significant reduction in joint actuation power, thereby validating the effectiveness and rationality of the proposed optimization strategy. This work establishes a theoretical foundation and technical pathway for the design of high-performance, heavy-duty legged robots in construction applications.