Tendon? Direct drive? What actually moves a robot hand | RLWRLD

We own most of the robot hands on the market. So we opened them up. So far, robot hands have mostly been actuated one of three ways — tendon drive, direct drive, and linkage. We put ours side by side: LEAP, ORCA from ETH, and the tendon hands that all come with a forearm full of motors. Each one buys you something and costs you something — power, size, and how often it breaks. Then we drilled into a linear actuator from the L20, the kind that sits three-per-finger inside the palm. What's in there is a lot smaller than you'd expect. Why we take hands apart: RLDX-1 has to run on all of them. Knowing how each hand actually moves is how the model gets better. RLDX-1 works across many different robot hands. See it on All Hands Up. 👉https://allhandsup.org/ Got a hand you want us to test next? Tell us in the comments. 00:00 Drilling into a $10K robot hand 00:43 Tendon vs. direct drive vs. linkage 01:18 LEAP: direct drive, and why it's too big 02:11 ORCA: open source and 3D printed 04:24 L20: linkage drive, 3 actuators per finger 05:54 Cracking open a linear actuator 07:53 Inside: a 2.3mm two-stage planetary gear 10:30 Why we take robot hands apart RLDX-1 here: RLDX-1 Tech Blog: https://rlwrld.ai/rldx-1 RLDX-1 Tech Report: https://arxiv.org/abs/2605.03269 GitHub: https://github.com/RLWRLD/RLDX-1 Hugging Face: https://huggingface.co/collections/RL... Follow us: Website: https://www.rlwrld.ai/ X: https://x.com/RLWRLD_ai LinkedIn:   / rlwrld   #rlwrld #robot #robotics