The paper presents a theoretical analysis of different vibration control strategies of soft mounted induction motors with sleeve bearings, using active motor foot mounts. After the vibration model is presented, differ...The paper presents a theoretical analysis of different vibration control strategies of soft mounted induction motors with sleeve bearings, using active motor foot mounts. After the vibration model is presented, different controllers in combination with different feedback strategies are mathematically investigated. The focus is here on the forced vibrations, caused by dynamic rotor eccentricity—rotor mass eccentricity, magnetic eccentricity and bent rotor deflection. After the mathematically coherences are described, a numerical example is shown, where the forced vibrations caused by bent rotor deflection are investigated, for different control strategies, where the mass matrix, the stiffness matrix and the damping matrix are influenced by different control parameters. The aim of the paper is to show the mathematically coherences and the possibility to influence the vibration behaviour, by different control strategies to optimize the vibration behaviour of soft mounted induction motors.展开更多
To explore lower rotating potint nutrient vessels of sural nerve flap with distant pedicled repairing the soft tissue defect of foot and ankle.Methods Lay a foundation of anatomic studying from february 2003 to March ...To explore lower rotating potint nutrient vessels of sural nerve flap with distant pedicled repairing the soft tissue defect of foot and ankle.Methods Lay a foundation of anatomic studying from february 2003 to March 2004,using lower rotating point nutrient vessels of sural nerve flap with distant pedicled repairing the soft tissue defect of foot and ankle in 11 cases.Cause of injuring:traffic accident 7 cases,crushing 1 case,saw injury 1 case,skin cancer 1 case,chronic ulcer 1 case.Areas:foot heel 6 cases,shank lower section 2 cases,heel tendon 2 cases,the distant back of the foot 1 case.Using the flap axis point was 1～3 cm above the pin of the external heel,average 2 cm.The scope of the flap was 6.0 cm×8.0 cm～12.0 cm～18.0 cm.Results All sural nerve flaps were alive.Of them,2 cases have distant part necrosis,accompanying with subcutaneous tissue,1 case heels after change dressings,another heels after skin grafting.All case can walk as usual,the flap was wear-resisting and keenly feel.Conclusion Lower rotating point nutrient vessels of sural nerve flap,donner area was fine,available area was large,skin in the pink,easy grafting,without main blood vessel damage,survival rate high,it is a good donner area in repairing around heel,foot and shank lower section.7 refs,1 tab.展开更多
Lizards use the synergy between their feet and tail to climb on slopes and vertical terrains.They use their soft adhesive feet with millions of small hairs to increase their contact area with the terrain surface and p...Lizards use the synergy between their feet and tail to climb on slopes and vertical terrains.They use their soft adhesive feet with millions of small hairs to increase their contact area with the terrain surface and press their tails against the terrain to actively maintain stability during climbing.Inspired by this,we propose a bio-inspired climbing robot based on a new approach wherein the synergy between soft feet and an active tail with a soft adhesive tip allows the robot to climb stably on even and uneven terrains at different slope angles.We evaluate and compare the climbing performance of the robot on three different terrains(hard,soft,and fluffy)at different slope angles.Various robot configurations are employed,including those with standard hard feet and soft feet in combination with an active tail-with and without a soft tip.The experimental results show that the robot having soft feet and a tail with the soft tip achieves the best climbing performance on all terrains,with maximum climbing slopes of 40°,45°,and 50°on fluffy,soft,and hard terrains,respectively.Its payload capacity depends on the type of terrain and the inclination angle.Moreover,our robot performs multi-terrain transitions(climbing from horizontal to sloped terrains)on three different terrains of a slope.This approach can allow a climbing robot to walk and climb on different terrains,extending the operational range of the robot to areas with complex terrains and slopes,e.g.,in inspection,exploration,and construction.展开更多
针对软土地层中压入式沉井的下沉稳定性控制问题,依托温州沉井式地下车库工程以压入式沉井法施工的超深地下车库,采用现场实测,研究压入式沉井下沉过程中的刃脚踏面端阻、斜面端阻以及整体端阻力在下沉阻力中占比的变化特征,分析静压下...针对软土地层中压入式沉井的下沉稳定性控制问题,依托温州沉井式地下车库工程以压入式沉井法施工的超深地下车库,采用现场实测,研究压入式沉井下沉过程中的刃脚踏面端阻、斜面端阻以及整体端阻力在下沉阻力中占比的变化特征,分析静压下沉与井内取土2个主要工序对端阻力的影响规律并与规范理论值进行对比。研究结果表明:1)压入下沉的方式对孔隙水压力影响较小,孔隙水压力受到刃脚穿越地层性质影响显著,且主要集中在静压前期;2)踏面压力与静压力大小呈正相关关系,且井内土塞高度越大,踏面压力受静压力影响越明显;3)斜面压力随静压下沉呈增大趋势,斜面压力受土塞高度影响较大,刃脚掏空阶段斜面压力将显著下降,当土芯率位于区间0.47~0.69时,下沉姿态对斜面压力的影响较大;4)踏面压力与斜面压力竖向上的差值基本保持在5~20 k Pa,受下沉深度影响较小,通过压力差值曲线可对沉井工况和状态进行初步判断;5)端阻力随下沉深度呈先增大后稳定趋势,增幅主要集中在地层交界面附近,同规范计算值基本吻合,端阻力随深度分布值受静压及取土工序影响较小,但数值上普遍小于规范值。展开更多
文摘The paper presents a theoretical analysis of different vibration control strategies of soft mounted induction motors with sleeve bearings, using active motor foot mounts. After the vibration model is presented, different controllers in combination with different feedback strategies are mathematically investigated. The focus is here on the forced vibrations, caused by dynamic rotor eccentricity—rotor mass eccentricity, magnetic eccentricity and bent rotor deflection. After the mathematically coherences are described, a numerical example is shown, where the forced vibrations caused by bent rotor deflection are investigated, for different control strategies, where the mass matrix, the stiffness matrix and the damping matrix are influenced by different control parameters. The aim of the paper is to show the mathematically coherences and the possibility to influence the vibration behaviour, by different control strategies to optimize the vibration behaviour of soft mounted induction motors.
文摘To explore lower rotating potint nutrient vessels of sural nerve flap with distant pedicled repairing the soft tissue defect of foot and ankle.Methods Lay a foundation of anatomic studying from february 2003 to March 2004,using lower rotating point nutrient vessels of sural nerve flap with distant pedicled repairing the soft tissue defect of foot and ankle in 11 cases.Cause of injuring:traffic accident 7 cases,crushing 1 case,saw injury 1 case,skin cancer 1 case,chronic ulcer 1 case.Areas:foot heel 6 cases,shank lower section 2 cases,heel tendon 2 cases,the distant back of the foot 1 case.Using the flap axis point was 1～3 cm above the pin of the external heel,average 2 cm.The scope of the flap was 6.0 cm×8.0 cm～12.0 cm～18.0 cm.Results All sural nerve flaps were alive.Of them,2 cases have distant part necrosis,accompanying with subcutaneous tissue,1 case heels after change dressings,another heels after skin grafting.All case can walk as usual,the flap was wear-resisting and keenly feel.Conclusion Lower rotating point nutrient vessels of sural nerve flap,donner area was fine,available area was large,skin in the pink,easy grafting,without main blood vessel damage,survival rate high,it is a good donner area in repairing around heel,foot and shank lower section.7 refs,1 tab.
基金supported by the National Key R&D Program of China,Topic 4-NUAA(Grant No.2020 YFB1313504)to PM.
文摘Lizards use the synergy between their feet and tail to climb on slopes and vertical terrains.They use their soft adhesive feet with millions of small hairs to increase their contact area with the terrain surface and press their tails against the terrain to actively maintain stability during climbing.Inspired by this,we propose a bio-inspired climbing robot based on a new approach wherein the synergy between soft feet and an active tail with a soft adhesive tip allows the robot to climb stably on even and uneven terrains at different slope angles.We evaluate and compare the climbing performance of the robot on three different terrains(hard,soft,and fluffy)at different slope angles.Various robot configurations are employed,including those with standard hard feet and soft feet in combination with an active tail-with and without a soft tip.The experimental results show that the robot having soft feet and a tail with the soft tip achieves the best climbing performance on all terrains,with maximum climbing slopes of 40°,45°,and 50°on fluffy,soft,and hard terrains,respectively.Its payload capacity depends on the type of terrain and the inclination angle.Moreover,our robot performs multi-terrain transitions(climbing from horizontal to sloped terrains)on three different terrains of a slope.This approach can allow a climbing robot to walk and climb on different terrains,extending the operational range of the robot to areas with complex terrains and slopes,e.g.,in inspection,exploration,and construction.
文摘针对软土地层中压入式沉井的下沉稳定性控制问题,依托温州沉井式地下车库工程以压入式沉井法施工的超深地下车库,采用现场实测,研究压入式沉井下沉过程中的刃脚踏面端阻、斜面端阻以及整体端阻力在下沉阻力中占比的变化特征,分析静压下沉与井内取土2个主要工序对端阻力的影响规律并与规范理论值进行对比。研究结果表明:1)压入下沉的方式对孔隙水压力影响较小,孔隙水压力受到刃脚穿越地层性质影响显著,且主要集中在静压前期;2)踏面压力与静压力大小呈正相关关系,且井内土塞高度越大,踏面压力受静压力影响越明显;3)斜面压力随静压下沉呈增大趋势,斜面压力受土塞高度影响较大,刃脚掏空阶段斜面压力将显著下降,当土芯率位于区间0.47~0.69时,下沉姿态对斜面压力的影响较大;4)踏面压力与斜面压力竖向上的差值基本保持在5~20 k Pa,受下沉深度影响较小,通过压力差值曲线可对沉井工况和状态进行初步判断;5)端阻力随下沉深度呈先增大后稳定趋势,增幅主要集中在地层交界面附近,同规范计算值基本吻合,端阻力随深度分布值受静压及取土工序影响较小,但数值上普遍小于规范值。
