This paper presents a wheeled wall-climbing robot with the ability to climb concrete, brick walls using circular arrays of miniature spines located around the wheel. The robot consists of two driving wheels and a flex...This paper presents a wheeled wall-climbing robot with the ability to climb concrete, brick walls using circular arrays of miniature spines located around the wheel. The robot consists of two driving wheels and a flexible tail, just like letter “T”, so it is called Tbot. The simple and effective structure of Tbot enables it to be steerable and to transition from horizontal to vertical surfaces rapidly and stably. Inspired by the structure and mechanics of the tarsal chain in the Serica orientalis Motschulsky, a compliant spine mechanism was developed. With the bio-inspired compliant spine mechanism, the climbing performance of Tbot was improved. It could climb on 100° （10° past vertical） brick walls at a speed of 10 cm·s^-1. A mechanical model is also presented to analyze the forces acting on spine during a climbing cycle as well as load share between multi-spines. The simu- lation and experiment results show that the mechanical model is suitable and useful in the optimum design of Tbot.展开更多
High-performance donor-acceptor electron acceptors containing 2-(3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile(INCN)-type terminals are labile toward photooxidation and basic conditions,and new molecular designs ...High-performance donor-acceptor electron acceptors containing 2-(3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile(INCN)-type terminals are labile toward photooxidation and basic conditions,and new molecular designs toward electron acceptors that can achieve both high power conversion efficiencies and high stability are urgently needed.By replacing the central benzene ring in the classical ladder-type n-type semiconductor,2,2′-(indeno[1,2-b]fluorene-6,12-diylidene)dimalononitrile,with the electron-rich 4,4,9,9-tetrahexyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b′]dithiophene,we report herein the design of 2,2′-(7,7,15,15-tetrahexyl-7,15-dihydro-sindaceno[1,2-b:5,6-b′]diindeno[1,2-d]thiophene-2,10(2H)-diylidene)dimalononitrile(ITYM),a new type of all-fused-ring electron acceptor(AFRA).A threestep reaction including a key Pd-catalyzed double C-H activation/intramolecular cyclization is established for the efficient synthesis of such type of electron acceptors.ITYM is confirmed by singlecrystal X-ray analysis,which shows a planar nonacyclic structure with strongπ-πstacking.Compared with the classical carbon-bridged INCN-type acceptors,ITYM exhibits extraordinary stability with very promising performance.The AFRA concept opens a new avenue toward high-efficiency and-stability organic photovoltaics(OPVs).展开更多
基金Acknowledgment This work was supported by National Basic Re- search Program of China （No.2011 CB302106）, National Natural Science Foundation of China （No. 51005223） and Changzhou Science and Technology Support Pro- gram （CE20120081）. The authors would like to thank Dr Xiaojie Wang for his valuable advice and kind help in preparing this manuscript.
文摘This paper presents a wheeled wall-climbing robot with the ability to climb concrete, brick walls using circular arrays of miniature spines located around the wheel. The robot consists of two driving wheels and a flexible tail, just like letter “T”, so it is called Tbot. The simple and effective structure of Tbot enables it to be steerable and to transition from horizontal to vertical surfaces rapidly and stably. Inspired by the structure and mechanics of the tarsal chain in the Serica orientalis Motschulsky, a compliant spine mechanism was developed. With the bio-inspired compliant spine mechanism, the climbing performance of Tbot was improved. It could climb on 100° （10° past vertical） brick walls at a speed of 10 cm·s^-1. A mechanical model is also presented to analyze the forces acting on spine during a climbing cycle as well as load share between multi-spines. The simu- lation and experiment results show that the mechanical model is suitable and useful in the optimum design of Tbot.
基金The authors thank the National Key R&D Program of China(nos.2019YFA0705900 and 2017YFA0204701)the National Natural Science Foundation of China(nos.21661132006 and 91833304)for their financial support。
文摘High-performance donor-acceptor electron acceptors containing 2-(3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile(INCN)-type terminals are labile toward photooxidation and basic conditions,and new molecular designs toward electron acceptors that can achieve both high power conversion efficiencies and high stability are urgently needed.By replacing the central benzene ring in the classical ladder-type n-type semiconductor,2,2′-(indeno[1,2-b]fluorene-6,12-diylidene)dimalononitrile,with the electron-rich 4,4,9,9-tetrahexyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b′]dithiophene,we report herein the design of 2,2′-(7,7,15,15-tetrahexyl-7,15-dihydro-sindaceno[1,2-b:5,6-b′]diindeno[1,2-d]thiophene-2,10(2H)-diylidene)dimalononitrile(ITYM),a new type of all-fused-ring electron acceptor(AFRA).A threestep reaction including a key Pd-catalyzed double C-H activation/intramolecular cyclization is established for the efficient synthesis of such type of electron acceptors.ITYM is confirmed by singlecrystal X-ray analysis,which shows a planar nonacyclic structure with strongπ-πstacking.Compared with the classical carbon-bridged INCN-type acceptors,ITYM exhibits extraordinary stability with very promising performance.The AFRA concept opens a new avenue toward high-efficiency and-stability organic photovoltaics(OPVs).
