Paolo Pierro

TEO: FULL-SIZE HUMANOID ROBOT DESIGN POWERED BY A FUEL CELL SYSTEM

This article deals with the design of the full-size humanoid robot TEO, an improved version of its predecessor Rh-1. The whole platform is conceived under the premise of high efficiency in terms of energy consumption and optimization. We will focus mainly on the electromechanical structure of the lower part of the prototype, which is the main component demanding energy during motion. The dimensions and weight of the robotic platform, together with its link configuration and rigidity, will be optimized. Experimental results are presented to show the validity of the design.

A practical decoupled stabilizer for joint-position controlled humanoid robots

Efficient methods have so far been proposed for planning dynamically stable walking pattern for humanoid robots. However, to guarantee that the reference joint trajectory will produce a safe movement despite modeling errors and perturbations, a stabilizer needs to be implemented on the robot. Though this stabilizer constitutes an essential part of the control strategy of most advanced humanoid platform, it is usually not open-source and dedicated to the own robot characteristics. The goal of this paper is to propose a general and practical strategy for designing a stabilizer for joint-position controlled humanoid robots. The proposed method is based on a double inverted pendulum model and a decoupling approach thanks to which the position of the ZMP and the center of gravity can be controlled independently through the regulation of the ankle and hip joints. The stabilizer generates the expected stabilizing torques from the admissible joint position input. The resulting control algorithm is fast and can be easily executed on the robot. This algorithm was successfully implemented as real-time plugins for the OpenHRP simulator of the HRP2. Simulations showing the efficiency of the method are presented and discussed.

Modelling and control of the humanoid robot RH-1 for collaborative tasks

This work deals with the modelling and control of the humanoid robot RH-1, a full scale humanoid prototype totally developed in the University Carlos III of Madrid and the only one existing in our country. The main objective is to develop an advanced control system that allows cooperation tasks to be carried out semi-autonomously between humanoid robots and humans in real working environments. The kinematic model and a simplification of the dynamic model of the robot are presented in this paper, together with a control strategy for the stabilization of the system during the walking and collaborative actions. Several simulation and experimental results are also given along the paper to illustrate the work.

Humanoid robot RH-1 for collaborative tasks: a control architecture for human-robot cooperation

The full-scale humanoid robot RH-1 has been totally developed in the University Carlos III of Madrid. In this paper we present an advanced control system for this robot so that it can perform tasks in cooperation with humans. The collaborative tasks are carried out in a semi-autonomous way and are intended to be put into operation in real working environments where humans and robots should share the same space. Before presenting the control strategy, the kinematic model and a simplified dynamic model of the robot are presented. All the models and algorithms are verified by several simulations and experimental results.

Full-size humanoid robot TEO: Design attending mechanical robustness and energy consumption

This paper deals with the design of the full size humanoid robot TEO (Task Environment Operator), an improved version of its predecessor RH-1. The whole platform is conceived under the premise of high efficiency in terms of mechanical robustness and energy consumption. We will focus mainly on the electromechanical structure of the lower part of the prototype, which is the main component demanding energy during motion. The dimensions and weight of the robotic platform have been optimized and an approach regarding the energy source is also tackled, consisting of a fuel cell. Experimental results are presented to show the validity of the design.

A new approach on human-robot collaboration with humanoid robot rh-2

This paper presents a novel control architecture for humanoid robot RH-2. The main objective is that a robot can perform different tasks in collaboration with humans in working environments. In order to achieve this goal, two control loops have to be defined. The outer loop, called collaborative control loop, is devoted to the generation of stable motion patterns for a robot, given a specific manipulation task. The inner loop, called posture stability control loop, acts to guarantee the stability of humanoid for different poses determined by motion patterns. A case study is presented in order to show the effectiveness of the proposed control architecture.

User perception of usability aspects in indirect HRI - a chain of translations

This article reports on the results of a user study that investigates the perceived usability of naïve users conducting two navigation tasks with the HOAP-3 robot. In this user study, the robot was controlled via a Graphical User Interface (GUI) that enabled the users to navigate the robot in the physical environment. The main goal of the user study was to gain insights on the question if users assign usability issues mainly to the robot, the GUI, or both. The participants performed two tasks: (1) navigating the robot through a maze to find the exit, (2) navigating the robot through the maze to find an object. The user study was supplemented by the think aloud technique and the SUS questionnaire to investigate usability aspects. Furthermore, task duration and task completion were measured. The results stress that the users rated the overall usability of the navigation rather positive. They identified usability problems for both, the GUI and the robot itself. The participants made more suggestions for improving the interface than for improvement of the robot. A reflection on the think aloud data revealed, however, three underlying principles (“feeling of distance”, “lack of orientation”, and “lack of control” ) for the usability problems that were independent of the assignment to the GUI and the robot.

MODELING AND SIMULATION OF THE HUMANOID ROBOT HOAP-3 IN THE OPENHRP3 PLATFORM

The aim of this work is to model and simulate the humanoid robot HOAP-3 in the OpenHRP3 platform. Our purpose is to create a virtual model of the robot so that different motions and tasks can be tested in different environments. This will be the first step before testing the motion patterns in the real HOAP-3. We use the OpenHRP3 platform for the creation and validation of the robot model and tasks. The procedure followed to reach this goal is detailed in this article. In order to validate our experience, different walking motions are tested and the simulation results are compared with the experimental ones.

The virtual COM joints approach for whole-body rh-1 motion

The full-scale humanoid robot RH-1 has been totally developed in the University Carlos III of Madrid. In this paper we present a novel approach for controlling the motion of the whole body of RH-1 robot, so that it can perform tasks in collaboration with humans. Given the mechanical limitations of the robot platform, it is not possible to achieve completely tasks in collaboration with humans. The lack of degrees of freedom (DOF) in robot arms are compensated using the virtual prismatic joints of the center of mass of the robot. This way, the movements that cannot be accomplished by using only the arms are assisted by the movement of the legs. The whole stability of the robot is also guaranteed by the posture control. All the models and algorithms are verified by several simulations and experimental results.

Humanoid feet trajectory generation for the reduction of the dynamical effects

In this paper we present a different strategy for generating the trajectory of the swinging leg for a walking humanoid robot which takes into account the effects due to acceleration and velocities of the joints onto the center of mass of the robot. The trajectory of the leg is chosen to be constituted by two forth order polynomials interlaced by a via-point which satisfies the optimality criterium. This approach is validated on a humanoid robot HRP-2.