As cobots play an increasingly important role in industrial applications, the trend and industry demand for high load capacity, long reach, and lightweight are inevitable. How to improve the payload and reach capabilities while minimizing the increase in weight and ensuring end accuracy becomes a key scientific issue faced by cobots. Through an analysis of current technological routes, this paper believes that through the research of gravity compensation mechanisms, distributed dual-drive parallel mechanisms, and joint module’s integrated design methods, the payload capacity of cobots can be greatly improved while suppressing weight. By establishing lightweight design methods for robotic arm rods using internally porous structures and anisotropic load-bearing features inspired by bone-like structures, combined with new materials and additive manufacturing technology, a preparation scheme for lightweight and high stiffness arm rods can be formed. By establishing an arm rod displacement-vibration-deformation coupled control strategy, end accuracy can be ensured and vibration suppressed while achieving a lightweight design for the entire machine. By developing the above design and control key technologies, it will help improve the payload-reach to weight ratio of cobots.