Shanghai-based Kepler Robotics has announced the start of mass production and deliveries of its humanoid robot, the K2 “Bumblebee,” which it describes as the world’s first commercially available hybrid-architecture humanoid system. The K2 “Bumblebee” incorporates a hybrid serial-parallel design that combines planetary roller screw linear actuators with rotary actuators, a configuration intended to improve stability, extend operational life, and support high-load performance in industrial environments.
To achieve a human-like straight-knee walking gait, Kepler Robotics developed an approach based on planetary roller screw mechanics rather than quasi-direct-drive actuators. Reinforcement learning and imitation-based training were applied to reduce the gap between simulated and real-world performance, with GPU-accelerated physics simulation used to optimize walking strategies.
The robot is designed for industrial use cases such as logistics and manufacturing. It can operate for up to eight hours on a single charge, achieve an energy efficiency of 81.3 percent, and carry payloads of up to 30 kilograms with its dual arms. It is priced at RMB 248,000 (approximately USD 34,000), placing it below the million-yuan cost of earlier prototype systems.
Kepler Robotics reports that it has signed framework agreements for several thousand units, with contract values in the hundreds of millions of yuan. Customers span industrial services, data operations, smart manufacturing, exhibitions, and specialized applications. The company is also working with partners across its supply chain to strengthen component sourcing, scale production, and support broader adoption.
Since early 2025, Kepler Robotics has completed three funding rounds, adding investors including Tao Motor, Friend, Zhaofeng, Hanwei, Jirfine Intelligent Equipment, Veichi, and Keli Sensing. The company states that it aims to address barriers such as fragmented standards and limited deployment infrastructure while expanding humanoid robot integration across sectors.
