The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
When a humanoid robot traverses uneven terrain, such as stairs, possible footstep positions are constrained and the robot must take large strides. For robots with relatively short leg lengths, making such big strides is kinematically challenging. Possible solutions include lowering the torso height, relying on fast and dynamic stepping, and reducing foot size. However, all of these methods negatively...
This paper provides an overview of the bipedal walking controller implemented on ESCHER, a new torque-controlled humanoid designed by Virginia Tech to compete in the DARPA Robotics Challenge (DRC). The robot's compliant control approach relies on an optimization-based inverse dynamics solver proposed in a previous publication. This work presents two unique features to improve stability on soft and...
This paper describes a practical method to construct real-time controllers to achieve locomotion and manipulation tasks with a humanoid robot. We propose a method to insert emergency stop functionality to each layer to avoid robot's falling down and joint overloads even if recognition and planning error exist. We explain implementation of multi-layered real-time controllers on HRP2 robot and application...
The classical Capture Point (CP) technique allows biped robots to take protective footsteps in case of a push or other disturbance, but only applies to flat terrain and a horizontally-moving Center of Mass (CoM). This paper generalizes the Capture Point technique to arbitrary terrains and CoM paths. Removing the CoM path constraint leads to an infinite number of Capture Points, each corresponding...
A well known strategy in biped locomotion to prevent falling in the presence of large disturbances is to modify next footstep positions of the robot. Solving this complex control problem for the overall model of the robot is a challenging task. Published methods employ either linear models or heuristics to determine those positions. This paper introduces a new optimization method using a nonlinear...
When executing whole-body motions, humans are able to use a large variety of support poses which not only utilize the feet, but also hands, knees and elbows to enhance stability. While there are many works analyzing the transitions involved in walking, very few works analyze human motion where more complex supports occur. In this work, we analyze complex support pose transitions in human motion involving...
We describe Team WPI-CMU's approach to the DARPA Robotics Challenge (DRC), focusing on our strategy to avoid failures that required physical human intervention. We implemented safety features in our controller to detect potential catastrophic failures, stop the current behavior, and allow remote intervention by a human supervisor. Our safety methods and operator interface worked: we avoided catastrophe...
Momentum control approaches have been successfully applied to balance controllers for humanoid robots due to their integrated controllability of ground reaction force and the center of pressure. In this paper, we introduce a trajectory-free reactive stepping controller using momentum control. The controller is characterized by moving passively in the direction of external pushes without attempting...
This paper enhances the Biologically Inspired Dead-beat (BID) controller from [1], to not only enable three-dimensional bipedal running on a horizontal plane but also on 3D stepping-stones. Further contributions of the paper are explicit foot step targeting during running, leg cross-over avoidance and the embedding of the BID controller into a QP-based whole-body controller. The BID controller is...
This paper presents the development of a quadruped robot and introduces its trotting control algorithm. Dynamic control of a four-leg robot is not an easy task. Several attentions are required especially on the stability aspect. During trotting, the quadruped robot is supported only by its two diagonal legs. In this stage, the robot is unstable and easy to fall over. The instability becomes even worse...
Pedestrian small group is an important part of crowds in public places, they maintain similar speed and direction to reach the destination together through interactive cooperation. However, the research into the influence of groups on pedestrian flow dynamics has been limited. Previous research into the group behaviors mainly focus on the influence of group size on walking speed and spatial pattern...
Ability of quadruped robots for adjusting posture for crossing natural obstacles is an important issue. These robots should change their footholds to avoid any obstacles. In this paper, a gait planning algorithm based on Cartesian CPG-based controller for a quadruped robot in order to cross different planar obstacles will be developed. In proposed approach, the rhythmic patterns in central pattern...
Quadruped animals have high agility and grace skills in the motion over natural environment. An important feature of such animals is their abilities in the selection of appropriate gait in the response to the terrain irregularities and also the smooth transition between them in order to increase the stability or conserve the energy. In this paper, a Cartesian CPG-based controller for the gait generation...
Obtaining the dynamical model of a system with high degrees of freedom (DOF) is an extremely tedious and error-prone task. On the other hand, designing suitable and energy efficient gaits for legged robots is a difficult procedure due to the large number of parameters that require tuning and calibration. In this paper we obtain the equations of motion for a quadruped robot with 12 DOF and active spine...
In this paper, it is highly proposed to take into account of both heels and active toe joints during the walking of a biped robot with 7-DOF legs. The main goal of this research is to examine significance of exploiting heels and active toe joints on reducing the maximum knee joint torque as well as the total energy consumption. To this end, six different walking patterns are presented, while the main...
In this paper, we propose a leg compliance method and strategies for ZMP-based bipedal walking robot on continuous uneven terrain without gyro sensor by combining soft joint, impedance, force and position control. We divide biped robot into support leg and swing leg to apply different control methods, and distinguish period of swing leg into four procedures, which adopt different strategies. By this...
One of the primary advantage of walking machines is their inherent capacity to operate in different terrains. However, it is necessary a locomotion system for planning in advance future footholds, and to modify the robot gait in order to maintain the platform stability. Several locomotion systems have been developed for rectangular hexapod robots, in this work a system for radially a symmetric hexapod...
The development of mobile robots is related to multidisciplinary areas of mechanics, electronics, computing and biology. Current research have made possible the development of robots that assist in exploration, rescue and rehabilitation, using artificial intelligence techniques, optimization and dynamic analysis of multibody systems. This work aims the synthesis of a humanoid robot and presents the...
In this paper, we resolve the issue of stepping over a large obstacle by exploiting the redundancy of pelvis rotation and the versatility of foot trajectories for the humanoids. The control framework consists of a motion pattern that exploits the redundancy of pelvis rotation to enlarge the kinematic workspace, a generic foot trajectory generation which can be modified by a parametric interface to...
A plantar pressure study that is independent of age, height, mass, and shoe size, and which contributes to a normative database has not yet been developed. Plantar pressure data have been recognized as an important element in the assessment of patients with neuromusculoskeletal disorders. A normative plantar pressure distribution data for asymptomatic adult individuals encompassing the major daily...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.