1
|
Zhang ZW, Liu GF, Zheng TJ, Li HW, Zhao SK, Zhao J, Zhu YH. Blending control method of lower limb exoskeleton toward tripping-free stair climbing. ISA Trans 2022; 131:610-627. [PMID: 35697540 DOI: 10.1016/j.isatra.2022.05.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 05/19/2022] [Accepted: 05/22/2022] [Indexed: 06/15/2023]
Abstract
Tripping frequently occurs when an individual climbs the stairs with improper foot clearance. Among older adults, falling down the stairs accounts for over 10% of accidental deaths. This paper proposes an exoskeleton control method that blends human-dominant and exoskeleton-dominant control to prevent tripping. The blending controller not only allows the exoskeleton to track the pilot's movements and provide power assistance during regular walking, but also allows the exoskeleton to help the pilot avoid dangers in some cases. An online path planning method is used to generate a safe trajectory in the exoskeleton-dominant mode to help the pilot correct their running trajectory. The controller provides the pilot with adjustment spaces to adapt to sudden changes in the motion mode and enable active self-regulation. The simulations verified the effectiveness of the proposed blending method. Experiments showed that the robot should be involved in the pilot's movements when the foot clearance exceed the safety threshold to prevent tripping.
Collapse
Affiliation(s)
- Z W Zhang
- 150080 State Key Laboratory of Robotics & Systems, Harbin, China; 528200 Ji Hua Laboratory, Foshan, China
| | - G F Liu
- 150080 State Key Laboratory of Robotics & Systems, Harbin, China
| | - T J Zheng
- 150080 State Key Laboratory of Robotics & Systems, Harbin, China
| | - H W Li
- 150080 State Key Laboratory of Robotics & Systems, Harbin, China
| | - S K Zhao
- 150080 State Key Laboratory of Robotics & Systems, Harbin, China
| | - J Zhao
- 150080 State Key Laboratory of Robotics & Systems, Harbin, China
| | - Y H Zhu
- 150080 State Key Laboratory of Robotics & Systems, Harbin, China.
| |
Collapse
|
2
|
Zhao SK, Ge ZY, Xiang Z, Xue GM, Yan HS, Wang ZT, Wang Z, Xu HK, Su FF, Yang ZH, Zhang H, Zhang YR, Guo XY, Xu K, Tian Y, Yu HF, Zheng DN, Fan H, Zhao SP. Probing Operator Spreading via Floquet Engineering in a Superconducting Circuit. Phys Rev Lett 2022; 129:160602. [PMID: 36306769 DOI: 10.1103/physrevlett.129.160602] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 08/09/2022] [Accepted: 08/11/2022] [Indexed: 06/16/2023]
Abstract
Operator spreading, often characterized by out-of-time-order correlators (OTOCs), is one of the central concepts in quantum many-body physics. However, measuring OTOCs is experimentally challenging due to the requirement of reversing the time evolution of systems. Here we apply Floquet engineering to investigate operator spreading in a superconducting 10-qubit chain. Floquet engineering provides an effective way to tune the coupling strength between nearby qubits, which is used to demonstrate quantum walks with tunable couplings, reversed time evolution, and the measurement of OTOCs. A clear light-cone-like operator propagation is observed in the system with multiple excitations, and has a nearly equal velocity as the single-particle quantum walk. For the butterfly operator that is nonlocal (local) under the Jordan-Wigner transformation, the OTOCs show distinct behaviors with (without) a signature of information scrambling in the near integrable system.
Collapse
Affiliation(s)
- S K Zhao
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - Zi-Yong Ge
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Zhongcheng Xiang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - G M Xue
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - H S Yan
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Z T Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Zhan Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - H K Xu
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - F F Su
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Z H Yang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - He Zhang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Yu-Ran Zhang
- Theoretical Quantum Physics Laboratory, RIKEN Cluster for Pioneering Research, Wako-shi, Saitama 351-0198, Japan
| | - Xue-Yi Guo
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Kai Xu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- CAS Center for Excellence in Topological Quantum Computation, UCAS, Beijing 100190, China
| | - Ye Tian
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - H F Yu
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - D N Zheng
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
- CAS Center for Excellence in Topological Quantum Computation, UCAS, Beijing 100190, China
- Songshan Lake Materials Laboratory, Dongguan 523808, China
| | - Heng Fan
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- CAS Center for Excellence in Topological Quantum Computation, UCAS, Beijing 100190, China
- Songshan Lake Materials Laboratory, Dongguan 523808, China
| | - S P Zhao
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
- CAS Center for Excellence in Topological Quantum Computation, UCAS, Beijing 100190, China
- Songshan Lake Materials Laboratory, Dongguan 523808, China
| |
Collapse
|
3
|
Tang CL, Zhao SK, Huang C. [Features and advances of Morse taper connection in oral implant]. Zhonghua Kou Qiang Yi Xue Za Zhi 2017; 52:59-62. [PMID: 28072999 DOI: 10.3760/cma.j.issn.1002-0098.2017.01.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Dental implants have been widely accepted as a predictable and reliable tool for dental reconstruction with the development of the economy. The design of implant-abutment connections has influence on mechanical properties and biological characteristics of implants. There are two types of implant-abutment connections, the external and the internal connections. Morse taper connection is one of the internal connections and its conical shape creates significant friction via the high propensity of parallelism between the two structures within the joint space. Several studies showed that Morse taper connection performed well in terms of survival rate, stability, bacterial seal and marginal bone loss. Recently, clinical studies indicate implants combining Morse taper connection with platform switching are helpful in reducing marginal bone absorption. This review aims at analyzing the features and advantages of Morse taper connection.
Collapse
Affiliation(s)
- C L Tang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School of Stomatology, Wuhan University, Wuhan 430079, China
| | - S K Zhao
- The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School of Stomatology, Wuhan University, Wuhan 430079, China
| | - C Huang
- Department of Prosthodontics, School of Stomatology, Wuhan University, Wuhan 430079, China
| |
Collapse
|