The next trade in humanoid robotics may be less about the companies building the robots and more about the components that make them move.
Defiance ETFs on Tuesday launched the Defiance Robotics Actuators ETF (NYSE: AT), a fund focused specifically on robotics actuators.
The launch comes as humanoid robotics shifts from demonstrations and prototypes toward the more difficult task of scaling production. That shift could put greater focus on the supply chain for motors, gearboxes, screws, sensors and other precision-motion components.
Why Actuators are Becoming a Key Robotics Bet
McKinsey estimates actuators account for 40%-60% of a humanoid robot's bill of materials, making the category the largest hardware cost block. An actuator typically combines a gearbox, motor, driver, mechanical components and sensors, with the gearbox alone accounting for roughly 30%-50% of actuator costs.
The consultancy has also identified the robotics supply chain as a major constraint on humanoid scale, with many components still requiring custom development and qualification. Tesla, Inc.'s (NASDAQ: TSLA) Optimus, for example, has 28 joint actuators in its body and another 50 in its Gen 3 hands, according to McKinsey.
The timing of the launch comes as major humanoid developers move closer to scaled production. Tesla has been preparing its Optimus production lines, while XPeng Inc.- ADR (NYSE: XPEV) has said it has launched an automated production line for its IRON humanoid robot, where robots can assemble other robots.
XPeng has targeted large-scale production of IRON by the end of 2026. Together, the developments underscore the shift from demonstrating humanoid capabilities to building them at scale - potentially increasing demand for the precision components targeted by AT.
That makes the actuator layer potentially attractive to investors because component demand could rise regardless of which humanoid manufacturer ultimately emerges as the winner.
What AT Owns
AT's index requires companies to derive at least 50% of revenue from actuator systems, motion-control components or related technologies used in humanoids, collaborative robots and next-generation automation.
Its universe includes manufacturers of servo motors, harmonic and cycloidal reducers, precision gearboxes, ball screws, linear actuators, encoders, bearings and integrated actuator modules, as well as humanoid and consumer robot companies.
The index targets at least 25 constituents, with no individual stock allowed to exceed 8%. The fund has significant exposure to Japan and China.
The investment case is already beginning to show up in supplier agreements. Schaeffler, for instance, agreed earlier this year to become the preferred supplier for more than half of Humanoid's joint-actuator demand through 2031, covering at least 1 million actuators.
For AT, therefore, the humanoid opportunity is not simply a bet on which robot wins. It is a bet that every winner will need something to move.
The fund seeks to track the MarketVector Humanoid Actuator Index and charges an expense ratio of 0.69%.