Design of Vertebrae-Inspired Trunk Mechanism for Robust and Directive Quadruped Locomotion on Rough Terrain Without Requiring Sensing and Actuation

2017 ◽  
Vol 29 (3) ◽  
pp. 546-555 ◽  
Author(s):  
Takashi Takuma ◽  
◽  
Yoshiki Murata ◽  
Wataru Kase
Keyword(s):  
Rigid Body ◽  
Success Rate ◽  
Design Principle ◽  
Quadruped Robot ◽  
Rough Terrain ◽  
Elastic Coefficient ◽  
Sensors And Actuators ◽  
Quadruped Locomotion ◽  
Trunk Posture ◽  
Simulation Results

[abstFig src='/00290003/10.jpg' width='300' text='Quadruped robot equipping a vertebrae-inspired trunk mechanism' ] Quadrupedal animals adaptively change their trunk posture in order to avoid falling down and to facilitate directive locomotion even on rough terrain. This paper focuses on an animal-like trunk mechanism which has passive viscoelastic joints. The effect of the trunk mechanism is observed by changing the elasticity and configuration of joints. Simulation results showed that the locomotion success rate of a robot equipped with the trunk mechanism on rough terrain is higher than the locomotion success rate of a robot equipped with a rigid body. In addition, the distribution of the success rate changes according to the elastic coefficient, number, configuration, and type of joints. These results suggest a design principle for the trunk mechanism of a quadruped robot in order to obtain robust and directive locomotion without requiring sensors and actuators.

scholarly journals Self-Stabilizing Dynamics for a Quadruped Robot and Extension Toward Running on Rough Terrain

2007 ◽  
Vol 19 (1) ◽  
pp. 3-12 ◽  
Author(s):  
Zu Guang Zhang ◽  
◽  
Hiroshi Kimura ◽  
Yasuhiro Fukuoka ◽  
◽  
...  
Keyword(s):  
Control Strategy ◽  
Pitch Angle ◽  
Energy Input ◽  
Adaptation Strategy ◽  
Quadruped Robot ◽  
Delayed Feedback Control ◽  
Rough Terrain ◽  
Autonomous Adaptation ◽  
Good Energy ◽  
Simulation Results

We designed and analyzed a control strategy that achieves autonomous adaptation and good energy efficiency in running by a quadruped robot. Our control strategy, inspired by previous studies on self-stabilizing dynamics, combines rhythm and torque generators with delayed feedback control (DFC) to achieve stable running and essential energy input. We developed an adaptation strategy to extend this control strategy that adjusts the robot’s leg touchdown angle based on the body’s pitch angle. Used together with our proposed control, it enables robust bounding over a shallow slope. Simulation results confirmed the feasibility of our proposal and its performance.

Rush: A simple and autonomous quadruped running robot

2009 ◽  
Vol 223 (3) ◽  
pp. 323-336 ◽  
Author(s):  
Z G Zhang ◽  
H Kimura
Keyword(s):  
System Design ◽  
Control Strategy ◽  
Energy Efficient ◽  
Sensory Feedback ◽  
Quadruped Robot ◽  
Rough Terrain ◽  
Simulation Studies ◽  
Simulation Results

In this paper, the system design and analysis of a quadruped robot, Rush, are presented. The quadruped robot was fabricated to study autonomous and efficient running on flat and rough terrain. It is a compact, kneed, four-legged machine with only one actuator per compliant leg. A novel control strategy for the quadruped robot has been proposed in consideration of several engineering limitations on sensory feedback. Several simulation studies have already been performed to confirm the validity of the control strategy in the previous reports. In this paper, the results obtained from experiments with Rush are found to agree with the simulation results. The reported work may help improve the understanding of energy-efficient running locomotion and the simple control required to autonomously stabilize it on flat or rough terrain.

Influences of Diaphragm Springs on Operation Performances of Sight-Stabilizing Mechanism

2011 ◽  
Vol 211-212 ◽  
pp. 384-388
Author(s):  
Gui Mei Guo ◽  
Lin Hong
Keyword(s):  
Rigid Body ◽  
Structural Parameters ◽  
Angular Displacement ◽  
Kinematics And Dynamics ◽  
Analysis Method ◽  
Structure Form ◽  
Simulation Results ◽  
Fix Point ◽  
The Moment

Sight-stabilizing mechanisms controlled by diaphragm springs and other damping elements is an important subordinate system of airborne sight stabilizing System. The performances of sight-stabilizing system depend on the characteristics of kinematics and dynamics of the system in a great extent. Among various external moments acting on the rod of the manipulator, such as those moments caused by damper, positioning spring, and restoration spring, the forces by diaphragm springs are most obvious. According to the structure form and motion peculiarity, the rod can be equivalent to a rigid body turning around a fix point. Simulation results reveal that the moment of the restoration spring to the rod is proportional to the angular displacement, and that the moment is the most prominent factor influencing the operating performances among all these moments. Through reasonable adjustments of structural parameters of the restoration spring, the performances of the sight-stabilizing system can be improved greatly; the analysis method provides a basis for guiding the design of concerned structural parameters of sight-stabilizing system.

Comparison of Molecular Simulation and Pseudo-Rigid-Body Model Predictions for a Carbon Nanotube–Based Compliant Parallel-Guiding Mechanism

2008 ◽  
Vol 130 (4) ◽  
Author(s):  
Christopher M. DiBiasio ◽  
Martin L. Culpepper ◽  
Robert Panas ◽  
Larry L. Howell ◽  
Spencer P. Magleby
Keyword(s):  
Rigid Body ◽  
Molecular Simulation ◽  
Moment Of Inertia ◽  
Bulk Deformation ◽  
Body Model ◽  
Kinematic Behavior ◽  
Model Predictions ◽  
Rigid Body Model ◽  
Simulation Results ◽  
Selection Of

We report on the accuracy of the pseudo-rigid-body model (PRBM) in predicting the behavior of a nanoscale parallel-guiding mechanism (nPGM) that uses two single-walled (5,5) carbon nanotubes (CNTs) as the flexural guiding elements. The nPGM has two regions of behavior: region 1 is governed by the bulk deformation of the nanotubes, and region 2 is characterized by hingelike flexing of four “kinks” that occur due to buckling of the nanotube walls. PRBM parameters for (5,5) CNTs are proposed. Molecular simulation results of region 1 behavior match PRBM predictions of (1) kinematic behavior with less than 7.3% error and (2) elastomechanic behavior with less than 5.7% error. Although region 1 is of more interest because of its well-defined and stable nature, region 2 motion is also investigated. We show that the PRBM parameters are dependent on the selection of the effective tube thickness and moment of inertia, the lesson being that designers must take care to consider the thickness and moment of inertia values when deriving PRBM constants.

scholarly journals Stateless IoT

Information ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 85 ◽  
Author(s):  
Augusto Ciuffoletti
Keyword(s):  
Energy Saving ◽  
Design Principle ◽  
Internal State ◽  
Use Case ◽  
System Operation ◽  
Sensors And Actuators ◽  
Iot Applications ◽  
Basic Model ◽  
Energy Footprint ◽  
Save Energy

Energy consumption is a relevant matter in the design of IoT applications. Edge units—sensors and actuators—save energy by operating intermittently. When idle, they suspend their operation, losing the content of the onboard memory. Their internal state, needed to resume their work, is recorded on external storage: in the end, their internal operation is stateless. The backend infrastructure does not follow the same design principle: concentrators, routers, and servers are always-on devices that frustrate the energy-saving operation of edge devices. In this paper, we show how serverless functions, asynchronously invoked by the stateless edge devices, are an energy-saving option. We introduce a basic model for system operation and energy footprint evaluation. To demonstrate its soundness, we study a simple use case, from the design to a prototype.

scholarly journals Learning the Cost Function for Foothold Selection in a Quadruped Robot

Sensors ◽  
2019 ◽  
Vol 19 (6) ◽  
pp. 1292 ◽  
Author(s):  
Xingdong Li ◽  
Hewei Gao ◽  
Fusheng Zha ◽  
Jian Li ◽  
Yangwei Wang ◽  
...  
Keyword(s):  
Cost Function ◽  
Weight Vector ◽  
Quadruped Robot ◽  
Training Data ◽  
Rough Terrain ◽  
Weighted Sum ◽  
Data Set ◽  
Tof Camera ◽  
The Cost ◽  
Terrain Features

This paper is focused on designing a cost function of selecting a foothold for a physical quadruped robot walking on rough terrain. The quadruped robot is modeled with Denavit–Hartenberg (DH) parameters, and then a default foothold is defined based on the model. Time of Flight (TOF) camera is used to perceive terrain information and construct a 2.5D elevation map, on which the terrain features are detected. The cost function is defined as the weighted sum of several elements including terrain features and some features on the relative pose between the default foothold and other candidates. It is nearly impossible to hand-code the weight vector of the function, so the weights are learned using Supporting Vector Machine (SVM) techniques, and the training data set is generated from the 2.5D elevation map of a real terrain under the guidance of experts. Four candidate footholds around the default foothold are randomly sampled, and the expert gives the order of such four candidates by rotating and scaling the view for seeing clearly. Lastly, the learned cost function is used to select a suitable foothold and drive the quadruped robot to walk autonomously across the rough terrain with wooden steps. Comparing to the approach with the original standard static gait, the proposed cost function shows better performance.

Optimization of a Planar Quadruped Dynamic Leap

2008 ◽  
Author(s):  
Subhrajit Bhattacharya ◽  
Sachin Chitta ◽  
Vijay Kumar ◽  
Daniel Lee
Keyword(s):  
Quadruped Robot ◽  
Experimental Results ◽  
Walking Robots ◽  
Rough Terrain

Quadruped walking robots need to handle high obstacles like steps that are often not kinematically reachable. We present a dynamic leap that allows a quadruped robot to put its front legs up onto a high rock or ledge, a motion we have found is critical to being able to locomote over rough terrain. The leaping motion was optimized using a simulated planar quadruped model. We present experimental results for the implementation of this optimized motion on a real quadruped robot.

The Casting Process Design and Simulation of the Volute of 65ZGB Slurry Pump

2010 ◽  
Vol 29-32 ◽  
pp. 1574-1577 ◽  
Author(s):  
Xiao Hui Zhi ◽  
Yan Jun Han ◽  
Hai Hua Wang
Keyword(s):  
Process Parameters ◽  
Process Design ◽  
Design Principle ◽  
Casting Process ◽  
Shrinkage Defects ◽  
Simulation Results ◽  
Simulation Parameters

The casting process design and simulation of the volute of 65ZGB slurry pump were presented in this paper. The casting process design principle, process parameters, points of attention, and the simulation parameters were introduced. Huazhu CAE was used to simulate the casting process. The STL document used in Huazhu CAE was converted from the 3D moulding of the casting process using the Solidwork software. The simulation results and practical production showed that the casting process can reduce shrinkage defects of the casting.

Research on Statistics Based Multi-Priority MAC Protocol for Ad Hoc Networks

2014 ◽  
Vol 644-650 ◽  
pp. 3103-3107
Author(s):  
Peng Wang ◽  
Hai Li ◽  
Ben Li Ye ◽  
Chen Chen ◽  
Yu Bao Wang
Keyword(s):  
Ad Hoc Networks ◽  
Success Rate ◽  
Ad Hoc ◽  
Mac Protocol ◽  
Medium Access ◽  
Critical Data ◽  
Low Delay ◽  
Simulation Results ◽  
Hoc Networks ◽  
Application Diversification

With the growing application diversification in Ad Hoc networks, it is particularly important to support prioritization of traffic and ensure that critical data can be delivered more reliably and faster in an emergency scene. We mainly study on the improvement of statistics based multi-priority medium access control (MAC) protocol, including the channel occupancy statistic and the backoff mechanism. We conduct comprehensive simulations based on the OPNET Modeler and account for the success rate results with theoretical analysis. The simulation results show that the proposed algorithm can simultaneously guarantee high success rate and low delay for high-priority packets.

Sign in / Sign up

Export Citation Format

Share Document