Walking without impacts has been considered in dynamics as a motion/force control problem. In order to avoid impacts, an approach for both the specified motion of the biped and its ground reaction forces was presented...Walking without impacts has been considered in dynamics as a motion/force control problem. In order to avoid impacts, an approach for both the specified motion of the biped and its ground reaction forces was presented yielding a combined motion and force control problem. As an application, a walker on a horizontal plane has been considered. In this paper, it is shown how the control of the ground reaction forces and the energy consumption depend on the gradient of a slope. The biped dynamics and the constraints within the biped system and on the ground are discussed. A motion control synthesis is developed using the inverse dynamics principle proven to be most efficient for human walking research, too. The impactless walking with controlled legs is illustrated by a seven-link biped. The ＂flying＂ biped has nine degrees of freedom, with six control inputs. During locomotion, the standing leg has three scleronomic constraints, and the trunk has three rheonomic constraints. However, there are three rheonomic constraints for the prescribed leg motion or three scleronomic constraints for reaction forces of the trailing leg, respectively. The nominal control action for impactless walking can be precomputed and stored. The model proposed allows the investigation of several problems： uphill and downhill walking, optimization of step length,stiction of the feet on the slope and many more. All these findings are also of interest in biomechanics. C 2013 The Chinese Society of Theoretical and Applied Mechanics. [doi：10.1063/2.1301302]展开更多
The stable slope-walking ability of legged robot walking in any direction on slope is analysed. The contacting angle and leaving angle of leg to the ground are presented. A method to increase the slope-walking ability...The stable slope-walking ability of legged robot walking in any direction on slope is analysed. The contacting angle and leaving angle of leg to the ground are presented. A method to increase the slope-walking ability is proposed only by changing the contacting angle and leaving angle of the leg to the ground.展开更多
The purpose of this study was to compare the ventilatory threshold (VT) between treadmill walking against a horizontal impeding force (horizontal load walking) and a cycle ergometer exercise. Seven adult men volunteer...The purpose of this study was to compare the ventilatory threshold (VT) between treadmill walking against a horizontal impeding force (horizontal load walking) and a cycle ergometer exercise. Seven adult men volunteered to participate in this study. They performed horizontal load walking (velocity: 1.11 m/s) and a cycle ergometer exercise (pedaling frequency: 60 rpm), with loads imposed using a ramp slope technique. Oxygen uptake at the VT during horizontal load walking was greater than that during a cycle ergometer exercise展开更多
To study the walking status of a goat on slope and the walking mechanics,a comparative analysis of the walking gait mode of a goat on different slopes was conducted.The uphill and downhill walking processes on differe...To study the walking status of a goat on slope and the walking mechanics,a comparative analysis of the walking gait mode of a goat on different slopes was conducted.The uphill and downhill walking processes on different slopes(6°,18°and 36°)were recorded by a high speed video system.The experimental image results were processed and analyzed via SigmaScan software and MATLAB software.The characteristic parameters of locomotion gait on the different slopes and the angle change curves of each goat leg in the process of slope movement indicated that the goat performed tetrapod gait,static gait,ipsilateral gait and trot gait on different slopes.With the increase of gradient in the uphill process,the corresponding load factors of each leg were 0.65±0.15,0.75 and 0.645±0.205,whereas those in the downhill process were 0.70±0.08,0.66±0.06,and 0.685±0.125.Results showed that the load factors of each leg are higher than 0.5.The foreleg angle ofa(the angle of wrist joints),which ranges from 100°to 130°,is suitable for different slopes.However,the angle ofb(the angle between the thigh and the forward direction in the walking process of goat),which ranges from 99°to 109°,is suitable for the 6°slope,whereas the angle ranging from 46°to 91°is suitable for the 18°slope and 36°slope.For the hind leg,the angle ofa,which ranges from 105°to 153°,is suitable for the different slopes.The angle ofb,which ranges from 128°to 150°,is suitable for the different slopes.The research can provide a theoretical basis and experimental data for the design of biomimetic agricultural slope walking mechanism.展开更多
基金supported by Overseas Training Program for Young Backbone Teachers from Tongji University, China(2010)
文摘Walking without impacts has been considered in dynamics as a motion/force control problem. In order to avoid impacts, an approach for both the specified motion of the biped and its ground reaction forces was presented yielding a combined motion and force control problem. As an application, a walker on a horizontal plane has been considered. In this paper, it is shown how the control of the ground reaction forces and the energy consumption depend on the gradient of a slope. The biped dynamics and the constraints within the biped system and on the ground are discussed. A motion control synthesis is developed using the inverse dynamics principle proven to be most efficient for human walking research, too. The impactless walking with controlled legs is illustrated by a seven-link biped. The ＂flying＂ biped has nine degrees of freedom, with six control inputs. During locomotion, the standing leg has three scleronomic constraints, and the trunk has three rheonomic constraints. However, there are three rheonomic constraints for the prescribed leg motion or three scleronomic constraints for reaction forces of the trailing leg, respectively. The nominal control action for impactless walking can be precomputed and stored. The model proposed allows the investigation of several problems： uphill and downhill walking, optimization of step length,stiction of the feet on the slope and many more. All these findings are also of interest in biomechanics. C 2013 The Chinese Society of Theoretical and Applied Mechanics. [doi：10.1063/2.1301302]
文摘The stable slope-walking ability of legged robot walking in any direction on slope is analysed. The contacting angle and leaving angle of leg to the ground are presented. A method to increase the slope-walking ability is proposed only by changing the contacting angle and leaving angle of the leg to the ground.
文摘The purpose of this study was to compare the ventilatory threshold (VT) between treadmill walking against a horizontal impeding force (horizontal load walking) and a cycle ergometer exercise. Seven adult men volunteered to participate in this study. They performed horizontal load walking (velocity: 1.11 m/s) and a cycle ergometer exercise (pedaling frequency: 60 rpm), with loads imposed using a ramp slope technique. Oxygen uptake at the VT during horizontal load walking was greater than that during a cycle ergometer exercise
基金the Project on the Integration of Industry,Education and Research of Henan Province(Grant No.142107000055)Natural Science Foundation of Henan Educational Committee(Grant Nos.14B416004,14A416002 and 13A416264)Innovation Ability Foundation of Natural Science of Henan University of Science and Technology(Grant No.2013ZCX002).
文摘To study the walking status of a goat on slope and the walking mechanics,a comparative analysis of the walking gait mode of a goat on different slopes was conducted.The uphill and downhill walking processes on different slopes(6°,18°and 36°)were recorded by a high speed video system.The experimental image results were processed and analyzed via SigmaScan software and MATLAB software.The characteristic parameters of locomotion gait on the different slopes and the angle change curves of each goat leg in the process of slope movement indicated that the goat performed tetrapod gait,static gait,ipsilateral gait and trot gait on different slopes.With the increase of gradient in the uphill process,the corresponding load factors of each leg were 0.65±0.15,0.75 and 0.645±0.205,whereas those in the downhill process were 0.70±0.08,0.66±0.06,and 0.685±0.125.Results showed that the load factors of each leg are higher than 0.5.The foreleg angle ofa(the angle of wrist joints),which ranges from 100°to 130°,is suitable for different slopes.However,the angle ofb(the angle between the thigh and the forward direction in the walking process of goat),which ranges from 99°to 109°,is suitable for the 6°slope,whereas the angle ranging from 46°to 91°is suitable for the 18°slope and 36°slope.For the hind leg,the angle ofa,which ranges from 105°to 153°,is suitable for the different slopes.The angle ofb,which ranges from 128°to 150°,is suitable for the different slopes.The research can provide a theoretical basis and experimental data for the design of biomimetic agricultural slope walking mechanism.
