Fauna Sprout: A lightweight, approachable, developer-ready humanoid robot

Fauna Robotics; :; Diego Aldarondo; Ana Pervan; Daniel Corbalan; Dave Petrillo; Bolun Dai; Aadhithya Iyer; Nina Mortensen; Erik Pearson; Sridhar Pandian Arunachalam; Emma Reznick; David Weis; Jacob Davison; Samuel Patterson; Tess Carella; Michael Suguitan; David Ye; Oswaldo Ferro; Nilesh Suriyarachchi; Spencer Ling; Erik Su; Daniel Giebisch; Peter Traver; Sam Fonseca; Mack Mor; Rohan Singh; Sertac Guven; Kangni Liu; Yaswanth Kumar Orru; Ashiq Rahman Anwar Batcha; Shruthi Ravindranath; Silky Arora; Hugo Ponte; Dez Hernandez; Utsav Chaudhary; Zack Walker; Michael Kelberman; Ivan Veloz; Christina Santa Lucia; Kat Casale; Helen Han; Michael Gromis; Michael Mignatti; Jason Reisman; Kelleher Guerin; Dario Narvaez; Christopher Anderson; Anthony Moschella; Robert Cochran; Josh Merel

arXiv · 2601.18963

Fauna Sprout: A lightweight, approachable, developer-ready humanoid robot

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Abstract

Recent advances in learned control, large-scale simulation, and generative models have accelerated progress toward general-purpose robotic controllers, yet the field still lacks platforms suitable for safe, expressive, long-term deployment in human environments. Most existing humanoids are either closed industrial systems or academic prototypes that are difficult to deploy and operate around people, limiting progress in robotics. We introduce Sprout, a developer platform designed to address these limitations through an emphasis on safety, expressivity, and developer accessibility. Sprout adopts a lightweight form factor with compliant control, limited joint torques, and soft exteriors to support safe operation in shared human spaces. The platform integrates whole-body control, manipulation with integrated grippers, and virtual-reality-based teleoperation within a unified hardware-software stack. An expressive head further enables social interaction -- a domain that remains underexplored on most utilitarian humanoids. By lowering physical and technical barriers to deployment, Sprout expands access to capable humanoid platforms and provides a practical basis for developing embodied intelligence in real human environments.

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Fauna Robotics, :, Diego Aldarondo, Ana Pervan, Daniel Corbalan, Dave Petrillo, Bolun Dai, Aadhithya Iyer, Nina Mortensen, Erik Pearson, Sridhar Pandian Arunachalam, Emma Reznick, David Weis, Jacob Davison, Samuel Patterson, Tess Carella, Michael Suguitan, David Ye, Oswaldo Ferro, Nilesh Suriyarachchi, Spencer Ling, Erik Su, Daniel Giebisch, Peter Traver, Sam Fonseca, Mack Mor, Rohan Singh, Sertac Guven, Kangni Liu, Yaswanth Kumar Orru, Ashiq Rahman Anwar Batcha, Shruthi Ravindranath, Silky Arora, Hugo Ponte, Dez Hernandez, Utsav Chaudhary, Zack Walker, Michael Kelberman, Ivan Veloz, Christina Santa Lucia, Kat Casale, Helen Han, Michael Gromis, Michael Mignatti, Jason Reisman, Kelleher Guerin, Dario Narvaez, Christopher Anderson, Anthony Moschella, Robert Cochran, Josh Merel. 2026-01-26. Fauna Sprout: A lightweight, approachable, developer-ready humanoid robot. https://arxiv.org/abs/2601.18963

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