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Current work
since 2018 (Postdoc) Development of human-centric production system
The idea is to develop a tool to monitor someone motion and warn him when he performing a motion that could lead to a backache or else. For example, it shall detects if someone is lifting an heavy object without folding his knees.

Publications
2018 Active shock absorber control in humanoid robot falls with nonlinear optimization on a reduced dynamics model
We propose a reduced-model-based analytic approach to active shock absorption by a falling humanoid robot at impact. We model the segment between the contact point at impact and the impacting limb extremity attached to the torso or waist of the humanoid robot as a one degree-of-freedom linear mass-spring-damper system. By mapping the joint angle limits and torque limits of the joints in the impacting limb to a corresponding position limit and force limit in the reduced model, we formulate a nonlinear optimization problem to find an admissible pair of parameters of the reduced model (stiffness, damping) that prevents the model from violating the constraints before reaching a steady state rest. The nonlinear constraints are analytically derived using symbolic computation tools and then numerically solved with off-the-shelf nonlinear optimization solver. The reduced model trajectories are then mapped back on the full body of the humanoid robot and illustrated on the HRP-4 robot in simulation. Submitted to ICRA 2018.
2017 Post-Impact Adaptive Compliance for Humanoid Falls Using Predictive Control of a Reduced Model
We consider control of a humanoid robot in active compliance just after the impact consecutive to a fall. The goal of this post-impact braking is to absorb undesired linear momentum accumulated during the fall, using a limited supply of time and actuation power. The gist of our method is an optimal distribution of undesired momentum between the robot's hand and foot contact points, followed by the parallel resolution of Linear Model Predictive Control (LMPC) at each contact. This distribution is made possible thanks to \emph{torque-limited friction polytopes}, an extension of friction cones that takes actuation limits into account. Individual LMPC results are finally combined back into a feasible CoM trajectory sent to the robot's whole-body controller. We validate the solution in full-body dynamics simulation of an HRP-4 humanoid falling on a wall. Humanoids 2017.
2017 QP-based Adaptive-Gains Compliance Control in Humanoid Falls
We address the problem of humanoid falling with a decoupled strategy consisting of a pre-impact and a post- impact stage. In the pre-impact stage, geometrical reasoning allows the robot to choose appropriate impact points in the surrounding environment and to adopt a posture to reach them while avoiding impact-singularities and preparing for the post-impact. The surrounding environment can be unstructured and may contain cluttered obstacles. The post-impact stage uses a quadratic program controller that adapts on-line the joint proportional-derivative (PD) gains to make the robot compliant –to absorb impact and post-impact dynamics, which lowers possible damage risks. This is done by a new approach incor- porating the stiffness and damping gains directly as decision variables in the QP along with the usually-considered variables of joint accelerations and contact forces. Constraints of the QP prevent the motors from reaching their torque limits during the fall. Several experiments on the humanoid robot HRP-4 in a full-dynamics simulator are presented and discussed. ICRA 2017.
2015 Falls control using posture reshaping and active compliance
We address the problem of humanoid falls when they are unavoidable. We propose a control strategy that combines two behaviors: i) closed-loop posture reshaping – during the falling phase, which allows best impact absorption from a predefined taxonomy, coupled with ii) an active compliance through instant PD gains reduction, instead of shutting-off the actuators or instead of high-gains control with additional implements as previously proposed by other works. We perform several simulations to assess our strategy and made experimental trials on the HRP-4 humanoid robot. Humanoids 2015.

Education
2014-2017 (Thesis) Humanoid fall control by postural reshaping and adaptive compliance
This thesis deals with the problem of humanoid falling with a decoupled strategy consisting of a pre-impact and a post-impact stages. In the pre-impact stage, geometrical reasoning allows the robot to choose appropriate impact points in the surrounding environment and to adopt a posture to reach them while avoiding impact singularities and preparing for the post-impact. The post-impact stage uses a quadratic program controller (QP) that adapts on-line the joint proportional-derivative (PD) gains to make the robot compliant, i.e. to absorb post-impact dynamics, which lowers possible damage risks. We propose a new approach incorporating the stiffness and damping gains directly as decision variables in the QP along with the usually-considered variables that are the joint accelerations and contact forces. Finally, to overcome the limitations of the local QP approach, we combine the method with a Model Predictive Controller (MPC) allowing for a preview on a time-horizon based on a reduced model. Several experiments on the real humanoid robot HRP-4 or in a full-dynamics simulator are presented and discussed to illustrate and validate each part of the thesis.
2014 - 2013 Master 2 in robotics (ENSAM Paris)
Master in robotics « Advanced Systems and Robotics » in cohabilitation with UPMC, ENSTA and ENS Cachan
2013 - 2008 Engineering degree « Design and Mechanical Engineering » (INSA Lyon)
Mechanical & Design deparment. Integrated preparatory class – section « ASINSA » which is linked with Asian culture.
2012 - 2011 Exchange year (神戸大学)
Done at the mechanical department of Kobe university.

Diverse experiences
2012 Study & research (Mechanical department of Kobe university, Japan)
The work seeked to minimize measurment errors of velocity sensors.
2011 In charge of the technics and the mise-en-scène
Realization of a 2h spectacle for the association named 'La semaine asiatique'. Creation of several comedy playlets. Assembling all the shows In charge of lights and sounds.
2009 Internship as a worker (SNR-NTN)
Learning the job of a worker at Iwata, Shizuoka prefecture, Japan. Packaging & quality control for 1 month.