A low-cost and lightweight 6 DoF bimanual arm for dynamic and contact-rich manipulation

TL;DR

ARMADA is an affordable, lightweight 6 DoF bimanual robot designed for dynamic, contact-rich manipulation, enabling complex tasks like snatching and throwing with high speed and low cost, suitable for research and RL applications.

Contribution

The paper introduces ARMADA, a low-cost, easy-to-assemble bimanual robot capable of dynamic manipulation, with open-source hardware and software for research use.

Findings

ARMADA achieves arm speeds up to 6.16 m/s.

Successfully performs real-world dynamic tasks like snatching and hammering.

Enables zero-shot transfer of RL policies from simulation to real world.

Abstract

Dynamic and contact-rich object manipulation, such as striking, snatching, or hammering, remains challenging for robotic systems due to hardware limitations. Most existing robots are constrained by high-inertia design, limited compliance, and reliance on expensive torque sensors. To address this, we introduce ARMADA (Affordable Robot for Manipulation and Dynamic Actions), a 6 degrees-of-freedom bimanual robot designed for dynamic manipulation research. ARMADA combines low-inertia, back-drivable actuators with a lightweight design, using readily available components and 3D-printed links for ease of assembly in research labs. The entire system, including both arms, is built for just $6,100. Each arm achieves speeds up to 6.16m/s, almost twice that of most collaborative robots, with a comparable payload of 2.5kg. We demonstrate ARMADA can perform dynamic manipulation like snatching, hammering, and bimanual throwing in real-world environments. We also showcase its effectiveness in reinforcement learning (RL) by training a non-prehensile manipulation policy in simulation and transferring it zero-shot to the real world, as well as human motion shadowing for dynamic bimanual object throwing. ARMADA is fully open-sourced with detailed assembly instructions, CAD models, URDFs, simulation, and learning codes. We highly recommend viewing the supplementary video at https://sites.google.com/view/im2-humanoid-arm.