A reconfigurable propulsion unit based on the Peaucellier-Lipkin mechanism has the ability to describe exact straight or curved paths depending on the selected ratio between the lengths of two of its links. The Peauce...A reconfigurable propulsion unit based on the Peaucellier-Lipkin mechanism has the ability to describe exact straight or curved paths depending on the selected ratio between the lengths of two of its links. The Peaucellier-Lipkin mechanism with one degree of freedom is transformed into a more sophisticated parallel kinematic chain by including four more degrees of freedom. The resulting propulsion unit is able to adapt its kinematic structure and reach instant centers of rotation, in accordance with the presence of three points that border a geometric path. A laser sensor mounted on the body of the machine detects each point. Once the machine has detected the exact location of the border of the road, it walks along a curve parallel to that border. Although the proposed research describes only one propulsion unit or leg, the methodology can be applied to all the legs of the walking machine. The novel 5-DOF leg is able to reach different centers of rotation, providing either the concave or convex arcs that satisfy the basic principle of displacement of walking machines.展开更多
The problem of walking machine leg transfer is considered.Optimal laws of transfer are determined with regard to geometrical features ofgroundand underwater.Complex optimality criterion is introduced as the sum of ind...The problem of walking machine leg transfer is considered.Optimal laws of transfer are determined with regard to geometrical features ofgroundand underwater.Complex optimality criterion is introduced as the sum of indexes of quality of the movement multiplied each by weight coefficients.The solution is provided based on the walking machine“Ortonog.”展开更多
This paper considers the geometric design of crab-like walkers and climbers, without decoupling leg design from overall machine design. Crab-like machines represent an important sub-class of multi-legged robots, bein...This paper considers the geometric design of crab-like walkers and climbers, without decoupling leg design from overall machine design. Crab-like machines represent an important sub-class of multi-legged robots, being particularly well suited to crossing difficult terrains. Firstly, the kinematic configurations and constraints are described, which determine the machine’s kinematic characteristics. The influence of the design parameters on the kinematic workspace is discussed. Finally, a two stage design methodology is presented, comprising kinematic design and design optimisation, the latter being based on the use of design maps rather than numerical optimisation. The performance measures considered during design optimisation include kinematic, static and quasi-static measures.展开更多
This paper presents our efforts to explain why mammals have large thigh muscles while insects have small ones. After a discussion of this observation a definition of body foot ratio is defined which describes how anim...This paper presents our efforts to explain why mammals have large thigh muscles while insects have small ones. After a discussion of this observation a definition of body foot ratio is defined which describes how animals stand and how their legs are arranged. To investigate the mechanics, we present a closed optimum solution of the body foot ratio for a 2D two-leg walking machine. A multi-walker is used as a case for 3D general analysis, and the numerical simulation is presented. Both 2D and 3D case studies can explain the above observations of mammals and insects. These findings can also be used as a guide for the design of man-made limbed machines.展开更多
ln order to raise the tractive efficiency of a boat-typc tractor further, according to a point of view about reducing energy consumption by reducing the volume of thc blade cavity, an idea of four-footed walkiag boat-...ln order to raise the tractive efficiency of a boat-typc tractor further, according to a point of view about reducing energy consumption by reducing the volume of thc blade cavity, an idea of four-footed walkiag boat-type tractor is put forward. and a walking device with two feet and four small wheels is designed and manufactured. It can move on the rails of a paddy soil bin to simulate the tractive performance of a boat-type tractor in thc paddy field. Kinematics and dynam- ics of the walking device is analysed. Because it can ensure that the blade foot enters and leaves the soil vertically, and eliminates the functions of the soil compression and pick by the blade entirely, so the volume of the blade cavity can be reduced to a minimum and the efficiency of the walking sys- tem has been rasied considerably. Thus, it is feasible to adopt a four-footed walking mechanism in the boat-type tractor.展开更多
基金Supported by Postgraduate Department of School of Mechanical Engineering,Universidad Michoacana de San Nicolás de Hidalgo,Francisco J.Múgica S/N Ciudad Universitaria,C.P.58030,Morelia,Michoacán,México
文摘A reconfigurable propulsion unit based on the Peaucellier-Lipkin mechanism has the ability to describe exact straight or curved paths depending on the selected ratio between the lengths of two of its links. The Peaucellier-Lipkin mechanism with one degree of freedom is transformed into a more sophisticated parallel kinematic chain by including four more degrees of freedom. The resulting propulsion unit is able to adapt its kinematic structure and reach instant centers of rotation, in accordance with the presence of three points that border a geometric path. A laser sensor mounted on the body of the machine detects each point. Once the machine has detected the exact location of the border of the road, it walks along a curve parallel to that border. Although the proposed research describes only one propulsion unit or leg, the methodology can be applied to all the legs of the walking machine. The novel 5-DOF leg is able to reach different centers of rotation, providing either the concave or convex arcs that satisfy the basic principle of displacement of walking machines.
基金The reported study was funded by RFBR,project number 19-31-90112.
文摘The problem of walking machine leg transfer is considered.Optimal laws of transfer are determined with regard to geometrical features ofgroundand underwater.Complex optimality criterion is introduced as the sum of indexes of quality of the movement multiplied each by weight coefficients.The solution is provided based on the walking machine“Ortonog.”
文摘This paper considers the geometric design of crab-like walkers and climbers, without decoupling leg design from overall machine design. Crab-like machines represent an important sub-class of multi-legged robots, being particularly well suited to crossing difficult terrains. Firstly, the kinematic configurations and constraints are described, which determine the machine’s kinematic characteristics. The influence of the design parameters on the kinematic workspace is discussed. Finally, a two stage design methodology is presented, comprising kinematic design and design optimisation, the latter being based on the use of design maps rather than numerical optimisation. The performance measures considered during design optimisation include kinematic, static and quasi-static measures.
文摘This paper presents our efforts to explain why mammals have large thigh muscles while insects have small ones. After a discussion of this observation a definition of body foot ratio is defined which describes how animals stand and how their legs are arranged. To investigate the mechanics, we present a closed optimum solution of the body foot ratio for a 2D two-leg walking machine. A multi-walker is used as a case for 3D general analysis, and the numerical simulation is presented. Both 2D and 3D case studies can explain the above observations of mammals and insects. These findings can also be used as a guide for the design of man-made limbed machines.
文摘ln order to raise the tractive efficiency of a boat-typc tractor further, according to a point of view about reducing energy consumption by reducing the volume of thc blade cavity, an idea of four-footed walkiag boat-type tractor is put forward. and a walking device with two feet and four small wheels is designed and manufactured. It can move on the rails of a paddy soil bin to simulate the tractive performance of a boat-type tractor in thc paddy field. Kinematics and dynam- ics of the walking device is analysed. Because it can ensure that the blade foot enters and leaves the soil vertically, and eliminates the functions of the soil compression and pick by the blade entirely, so the volume of the blade cavity can be reduced to a minimum and the efficiency of the walking sys- tem has been rasied considerably. Thus, it is feasible to adopt a four-footed walking mechanism in the boat-type tractor.
