Simeon Nedelchev

Simeon Nedelchev

I am a Researcher and Senior RL Engineer at the Institute of Artificial Intelligence, and Senior Lecturer at Innopolis University, where I teach robotics and advise students on dynamics, control, and simulation.

With a decade of experience spanning research labs, startups, industry, and big tech, I build control for articulated robots — from novel actuators, modeling, and adaptive methods to legged locomotion, reinforcement learning, whole-body control, and sim-to-real deployment. Completed Ph.D. studies in Computer Science (Robotics) at Innopolis University; M.Sc. degrees from Korea University of Technology and Education and STANKIN.

Contact: simkaned@gmail.com · Telegram


Recent Projects

One shared MDP for whole-body motion tracking in mjlab — train once on a motion library, deploy one policy for many skills. Multi-clip training, paper-specific task presets, and sim-to-real export.

Natural and robust humanoid locomotion via an offline predictor that maps lower-body state and velocity commands to upper-body and gait targets during RL training — preserving task-only deployment on Unitree G1.

Simeon Nedelchev, Ekaterina Chaikovskaia, Egor Davydenko, Eduard Zaliaev, Roman Gorbachev · 2026 preprint

LocoGen: Command-Conditioned Locomotion Generation
LocoGen command-conditioned generation in simulation LocoGen walking on Unitree G1 hardware

Combines learned motion matching and flow matching for online, command-conditioned full-body locomotion. Built for Unitree G1 but portable across robots: MuJoCo-grounded state, velocity commands (extensible to waypoints and trajectories), and interactive Viser control with seamless stand / walk / run transitions. Inference at ~800 FPS (LMM) and ~150 FPS (flow); PoC training from a handful of LAFAN clips. Walking and tracking validated with BeyondMimic / ZEST in simulation and on hardware.

Ongoing · code not yet published

Locomotion and Whole Body Control for Sber Green
Zero-shot dance tracking on Green humanoid Teleoperation with unified whole-body control policy
Natural RL locomotion on Green humanoid

Core senior engineer for RL locomotion and whole-body control on the Green humanoid at AIJ 2025: predictor-based human-like locomotion; unified WBC for teleoperation, dance, and zero-shot skills; motor & actuator system identification for MuJoCo simulation.

Batched differential inverse kinematics on MuJoCo Warp with a Mink-shaped API: GPU-parallel task-space IK for many worlds at once — frame tasks, posture, COM, equality constraints for closed chains, and hard limits via GPU ADMM. CUDA graph capture for real-time loops; Panda, UR5e, Cassie, dual iiwa, and G1 examples.


Experience

2026–now
Researcher & Senior RL Engineer
Institute of Artificial Intelligence
2023–2025
Senior Optimal Control & RL Engineer
Sber Robotics Center — developer of RL WBC and locomotion policies shown at AIJ 2025; control, modeling and MuJoCo simulation; partial motor/actuator system ID (video)
2022–now
Senior Lecturer
Institute for Robotics and Computer Vision, Innopolis University
2019–2023
Junior Researcher
Center for Technologies in Robotics and Mechatronics Components, Innopolis
2017–2019
Research Assistant
BioRobotics Laboratory, Korea University of Technology and Education

Open Source

Contributor to Pinocchio (rigid-body dynamics; inertia parametrizations and physical consistency), Pink (differential inverse kinematics for Pinocchio; tasks, constraints, and examples), Mink (MuJoCo port of Pink — EqualityConstraintTask for closed chains; humanoid and manipulation examples), mink-warp (batched differential IK on MuJoCo Warp; author), and GMR: General Motion Retargeting (SOMA BVH format and multi-robot configs). Contributor to mujoco-sysid (system identification in MuJoCo and MJX — dynamics regressors and parameter estimation). Co-author of MJINX: Differentiable GPU-accelerated Numerical IK (JAX and MuJoCo MJX).


Publications

View publications by year
2026
Predictive Style Matching: Natural and Robust Humanoid Locomotion
Simeon Nedelchev, Ekaterina Chaikovskaia, Egor Davydenko, Eduard Zaliaev, Roman Gorbachev · arXiv preprint
2025
Robust RL Control for Bipedal Locomotion with Closed Kinematic Chains
Egor Maslennikov, Eduard Zaliaev, Nikita Dudorov, Oleg Shamanin, Karanov Dmitry, Gleb Afanasev, Artem Burkov, Egor Lygin, Simeon Nedelchev, Evgeny Ponomarev · arXiv preprint
VIMPPI: Enhancing Model Predictive Path Integral Control with Variational Integration for Underactuated Systems
Igor Alentev, Lev Kozlov, Ivan Domrachev, Simeon Nedelchev, Jee-Hwan Ryu · arXiv preprint
2023
Enhanced Adaptive Control over Robotic Systems via Generalized Momentum Dynamic Extensions
Simeon Nedelchev, Lev Kozlov, Ramil Khusainov, Igor Gaponov · Russian Journal of Nonlinear Dynamics
Optimization Driven Robust Control of Mechanical Systems with Parametric Uncertainties
Charles A. Fam, Simeon Nedelchev · Russian Journal of Nonlinear Dynamics
Explicit Model Predictive Control Design based on Constrained Zonotope Propagation
Ali Jnadi, Ramil Khusainov, Simeon Nedelchev, Sergey Savin · DCNA 2023
2022
Design, characterisation and validation of a haptic interface based on twisted string actuation
Valeria Skvortsova, Simeon Nedelchev, Joshua Brown, Ildar Farkhatdinov, Igor Gaponov · Frontiers in Robotics and AI
2021
On Energy-Preserving Motion in Twisted String Actuators
Simeon Nedelchev, Valeria Skvortsova, Boris Guryev, Igor Gaponov, Jee-Hwan Ryu · IEEE RA-L
On Smooth Time-Optimal Trajectory Planning in Twisted String Actuators
Simeon Nedelchev, Daniil Kirsanov, Igor Gaponov, Hyeonseok Seong, Jee-Hwan Ryu · ICRA 2021
Parameter Identification in Mechanical Systems with Energy-Based Regressor: Preliminary Study
Alsu Sabirova, Simeon Nedelchev, Igor Gaponov · NIR 2021
2020
Accurate dynamic modeling of twisted string actuators accounting for string compliance and friction
Simeon Nedelchev, Igor Gaponov, Jee-Hwan Ryu · IEEE RA-L
IMU-based Parameter Identification and Position Estimation in Twisted String Actuators
Simeon Nedelchev, Daniil Kirsanov, Igor Gaponov · IROS 2020
Preliminary Study on Slack-Free Model Predictive Control of Twisted String-Based Antagonistic Joints
Oleg Balakhnov, Simeon Nedelchev, Igor Gaponov · NIR 2020
2019
High-bandwidth control of twisted string actuators
Simeon Nedelchev, Igor Gaponov, Jee-Hwan Ryu · ICRA 2019
2018
Design of robotic gripper with constant transmission ratio based on twisted string actuator
Simeon Nedelchev, Igor Gaponov, Jee-Hwan Ryu · IROS 2018
2017
Development of 2-DoF Adaptive Mechatronic Device with Corrective Adjustment of Laser Tracker Reflector for Industrial Robot Calibration
Denis Kosterev, Alexander Vorotnikov, Simeon Nedelchev, Evgeny Romash, Yuri Poduraev · Annals of DAAAM & Proceedings