Synthesis of multi-mode single-loop Bennett-based mechanisms using factorization of motion polynomials

A novel construction method is proposed to construct multimode deployable polyhedron mechanisms (DPMs) using symmetric spatial RRR compositional units, a serial kinematic chain in which the axes of the first and the third revolute (R) joints are perpendicular to the axis of the second R joint. Single-loop deployable linkages are first constructed using RRR units and are further assembled into polyhedron mechanisms by connecting single-loop kinematic chains using RRR units. The proposed mechanisms are over-constrained and can be deployed through two approaches. The prism mechanism constructed using two Bricard linkages and six RRR limbs has one degree-of-freedom (DOF). When removing three of the RRR limbs, the mechanism obtains one additional 1-DOF motion mode. The DPMs based on 8R and 10R linkages also have multiple modes, and several mechanisms are variable-DOF mechanisms. The DPMs can switch among different motion modes through transition positions. Prototypes are 3D-printed to verify the feasibility of the mechanisms.

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A reconfigurable multi-mode walking-rolling robot based on motor time-sharing control

Industrial Robot the international journal of robotics research and application ◽

10.1108/ir-05-2019-0106 ◽

2019 ◽

Vol 47 (2) ◽

pp. 293-311 ◽

Cited By ~ 1

Author(s):

Xiangyu Liu ◽

Chunyan Zhang ◽

Cong Ni ◽

Chenhui Lu

Keyword(s):

Topological Analysis ◽

Singularity Analysis ◽

Time Sharing ◽

Content Type ◽

Single Loop ◽

Motor Time ◽

Motion Modes ◽

Closed Chain ◽

Multi Mode ◽

Rolling Robot

Purpose The purpose of this paper is to put forward a nvew reconfigurable multi-mode walking-rolling robot based on the single-loop closed-chain four-bar mechanism, and the robot can be changed to different modes according to the terrain. Design/methodology/approach Based on the topological analysis, singularity analysis, feasibility analysis, gait analysis and the motion strategy based on motor time-sharing control, the paper theoretically verified that the robot can switch between the four motion modes. Findings The robot integrates four-bar walking, self-deforming and four-bar and six-bar rolling modes. A series of simulation and prototype experiment results are presented to verify the feasibility of multiple motion modes of the robot. Originality/value The work presented in this paper provides a good theoretical basis for further exploration of multiple mode mobile robots. It is an attempt to design the multi-mode mobile robot based on single loop kinematotropic mechanisms. It is also a kind of exploration of the new unknown movement law.

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Type Synthesis of Multi-mode Mobile Parallel Mechanism Based on Planar 4R Single-loop Kinematic Chains

Proceedings of the 2019 4th International Conference on Automation, Control and Robotics Engineering - CACRE2019 ◽

10.1145/3351917.3351920 ◽

2019 ◽

Author(s):

Xiangyu Liu ◽

Chunyan Zhang ◽

Cong Ni

Keyword(s):

Parallel Mechanism ◽

Type Synthesis ◽

Single Loop ◽

Kinematic Chains ◽

Multi Mode

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A Single-Loop 7R Spatial Mechanism That Has Three Motion Modes With the Same Instantaneous DOF but Different Finite DOF

Volume 5B: 42nd Mechanisms and Robotics Conference ◽

10.1115/detc2018-85125 ◽

2018 ◽

Author(s):

Xianwen Kong ◽

Andreas Müller

Keyword(s):

Higher Order ◽

Mobility Analysis ◽

Single Loop ◽

Plane Symmetric ◽

Spatial Mechanism ◽

Motion Modes ◽

Regular Configuration ◽

Kinematic Loop ◽

Multi Mode ◽

Motion Mode

Multi-mode mechanisms, including kinematotropic mechanisms, are a class of reconfigurable mechanisms that can switch motion modes with the same or different DOF (degree-of-freedom). For most of the multi-mode mechanisms reported in the literature, the instantaneous (or differential) DOF and finite DOF in a motion mode are equal. In this paper, we will discuss the construction, reconfiguration analysis, and higher-order mobility analysis of a multi-mode single-loop 7R mechanism that has three motion modes with the same instantaneous DOF but different finite DOF. Firstly, the novel multi-mode single-loop 7R spatial mechanism is constructed by inserting one revolute (R) joint into a plane symmetric Bennett joint-based 6R mechanism for circular translation. The reconfiguration analysis is then carried out in the configuration space by solving a set of kinematic loop equations based on dual quaternions and the natural exponential function substitution using tools from algebraic geometry. The analysis shows that the multi-mode single-loop 7R spatial mechanism has three motion modes, including a 2-DOF planar 5R mode and two 1-DOF spatial 6R modes and can transit between each pair of motion modes through two transition configurations. The higher-order mobility analysis shows that the 7R mechanism has two-instantaneous DOF at a regular configuration of any motion mode and three instantaneous DOF in a transition configuration. The infinitesimal motions that are not tangential to finite motions are of second-order in transition configurations between 2-DOF motion mode 1 and 1-DOF motion modes 2 or 3 or first-order in transition configurations between 1-DOF motion modes 2 and 3.

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Single-Loop Full R Joints of Multi-Mode Omnidirectional Ground Mobile Robot

Tehnicki vjesnik - Technical Gazette ◽

10.17559/tv-20200804125931 ◽

2021 ◽

Vol 28 (6) ◽

Keyword(s):

Mobile Robot ◽

Single Loop ◽

Multi Mode

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Multi-mode light microscopy of microtubule assembly dynamics and chromosome movement in vivo and In vitro

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100166117 ◽

1996 ◽

Vol 54 ◽

pp. 730-731

Author(s):

E. D. Salmon ◽

J. C. Waters ◽

C. Waterman-Storer

Keyword(s):

Imaging System ◽

Ccd Camera ◽

Transmitted Light ◽

Microtubule Assembly ◽

Live Cells ◽

Optical Efficiency ◽

Multiple Band ◽

Multi Mode

We have developed a multi-mode digital imaging system which acquires images with a cooled CCD camera (Figure 1). A multiple band pass dichromatic mirror and robotically controlled filter wheels provide wavelength selection for epi-fluorescence. Shutters select illumination either by epi-fluorescence or by transmitted light for phase contrast or DIC. Many of our experiments involve investigations of spindle assembly dynamics and chromosome movements in live cells or unfixed reconstituted preparations in vitro in which photodamage and phototoxicity are major concerns. As a consequence, a major factor in the design was optical efficiency: achieving the highest image quality with the least number of illumination photons. This principle applies to both epi-fluorescence and transmitted light imaging modes. In living cells and extracts, microtubules are visualized using X-rhodamine labeled tubulin. Photoactivation of C2CF-fluorescein labeled tubulin is used to locally mark microtubules in studies of microtubule dynamics and translocation. Chromosomes are labeled with DAPI or Hoechst DNA intercalating dyes.

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