Proof-of-Physical-Work (PoPW) has been a concept under consideration. At first glance, it seems simple, but in reality, it is quite solid — it verifies through cryptographic means that robots have indeed completed tasks in the real world. For example, in drone delivery of packages, after the system issues a task, the robot performs the work and generates a cryptographic proof, ensuring that each act of labor is credibly recorded. This approach combines real-world physical actions with the immutability of blockchain, opening up an interesting path — allowing the value of robots' work to be truly verified and transferred.