Fall Detection and Management in Biped Humanoid Robots

Abstract-The appropriate management of fall situationsi.e. fast instability detection, avoidance of unintentional falls, falling without damaging the body, fast recovering of the standing position after a fall -is an essential ability of biped humanoid robots. This issue is especially important for humanoid robots carrying out demanding movements such as walking in irregular surfaces, running or practicing a given sport (e.g. soccer). In a former contribution we have addressed the design of low-damage fall sequences, which can be activated/triggered by the robot in case of a detected unintentional fall or an intentional fall (common situation in robot soccer). In this article we tackle the detection of instability and the avoidance of falls in biped humanoids, as well as the integration of all components in a single framework. In this framework a fall can be avoided or a falling sequence can be triggered depending on the detected instability's degree. The proposed fall detection and fall avoidance subsystems are validated in real world-experiments with biped humanoid robots

A Kalman-filtering-based Approach for Improving Terrain Mapping in off-road Autonomous Vehicles

Artículo de publicación ISIThe generation of accurate terrain maps while navigating over off-road, irregular terrains is a complex challenge, due to the difficulties in the estimation of the pose of the laser rangefinders, which is required for the proper registration of the range measurements. This paper addresses this problem. The proposed methodology uses an Extended Kalman filter to estimate in real-time the instantaneous pose of the vehicle and the laser rangefinders by considering measurements acquired from an inertial measurement unit, internal sensorial data of the vehicle and the estimated heights of the four wheels, which are obtained from the terrain map and allow determination of the vehicle's inclination. The estimated 6D pose of the laser rangefinders is used to correctly project the laser measurements onto the terrain map. The terrain map is a 2.5D map that stores in each cell the mean value and variance of the terrain height. In each map's cell position, new laser observations are fused with existing height estimations using a Kalman filter. The proposed methodology is validated in the real world using an autonomous vehicle. Field trials show that the use of the proposed state estimation methodology produces maps with much higher accuracy than the standard approaches.FONDECYT 113015

Automatic Determination of Rock-Breaking Target Poses for Impact Hammers

This paper describes a system for the automatic determination of rock-breaking target poses for impact hammers used in underground mines. The rock-breaking target pose is defined as the position and angle at which the impact hammer must strike a rock in order to break it. The automatic determination of this pose is essential for the autonomous operation of an impact hammer. The proposed system takes as input sensor data composed of point clouds and images, and automatically determines a rock-breaking target pose. The system consists of a rock segmentation subsystem that receives the sensor data and identifies and individualizes the rocks/boulders present above the grizzly, and a rock-breaking target pose generation and evaluation subsystem that receives the rock information produced by the rock segmentation subsystem, and generates a list of rock-breaking target pose candidates, it evaluates them, and it selects the best candidate as the rock-breaking target pose. The system is evaluated using real data. The reported experiments show the system’s capability to generate appropriate target poses

Learning to fall: Designing low damage fall sequences for humanoid soccer robots

Artículo de publicación ISIA methodology for the analysis and design of fall sequences of robots that minimize joint/articulation injuries, and the damage of valuable body parts is proposed. These fall sequences can be activated/triggered by the robot in case of a detected unintentional fall or an intentional fall, which are common events in humanoid soccer environments. The methodology is human-based and requires the use of a realistic simulator as development tool. The obtained results show that fall sequences designed using the proposed method produce less damage than standard, uncontrolled falls.This research was partially funded by FONDECYT project 1090250, Chile

Robotics research in Chile: addressing the needs of the local mining industry at the Advanced Mining Technology Center

The development of research in robotics in a developing country is a challenging task. Factors such as low research funds, low trust from local companies and the government, and a small number of qualified researchers hinder the development of strong, local research groups. In this article, and as a case of study, we present our research group in robotics at the Advanced Mining Technology Center of the Universidad de Chile, and the way in which we have addressed these challenges. In 2008, we decided to focus our research efforts in mining, which is the main industry in Chile. We observed that this industry has needs in terms of safety, productivity, operational continuity, and environmental care. All these needs could be addressed with robotics and automation technology. In a first stage, we concentrate ourselves in building capabilities in field robotics, starting with the automation of a commercial vehicle. An important outcome of this project was the earn of the local mining industry confidence. Then, in a second stage started in 2012, we began working with the local mining industry in technological projects. In this article, we describe three of the technological projects that we have developed with industry support: (i) an autonomous vehicle for mining environments without global positioning system coverage; (ii) the inspection of the irrigation flow in heap leach piles using unmanned aerial vehicles and thermal cameras; and (iii) an enhanced vision system for vehicle teleoperation in adverse climatic conditionsFONDECYT (CHILE) Grant 1161500 GIZ (Germany) Grant "Accesible automation for a more efficient and safer underground mining in Chile'