Layout Guide for Design of a Novel Wheelchairs with Circumferential Linkage using Microsoft Word

In recent decades, the aging of the world’s population has intensified, and the number of people with disabilities caused by various disasters and diseases has gradually increased. Most of the elderly, frail and disabled people will choose wheelchairs as their means of transportation. However, ordinary wheelchairs are unable to climb stairs, especially in cities, which seriously limits the range of activities of wheelchair users and affects their daily life. Hence, it is of great significance and value to design an intelligent building climbing wheelchair with appropriate price, stability and safety. This paper designs a multi-functional planetary height adjustable building climbing wheelchair with simple structure and low price. Firstly, a multi-functional building climbing wheelchair based on planetary gear train is designed by using modular design idea, including ground walking mechanism, in place steering mechanism, center of gravity adjustment mechanism and Seat leveling mechanism. The working principle and design characteristics of each mechanism are analyzed in detail. Then, through the analysis of the mathematical model of the climbing mechanism, the dimensional parameters of the three-star wheel set are determined. According to the power demand of wheelchair, the power system is selected and analyzed. It provided a new possibility for the wheelchair application and also for those in need.

Analytical description of the process of operation of the hydraulic drive of the three-bearing walking mechanism of a dragline excavator

In the paper, an analytical formula is derived that allows to determine the acceleration of the movement of the piston of the hydraulic system at any moment of time. For the purpose of conducting the analytical studies, the most common dragline excavator used in surface mining operations, equipped with a hydraulically driven three-bearing walking mechanism, is selected. The derived formula has the form of the Cauchy formula and is solved on a computer by the Runge-Kutta method of the fourth order, which makes it possible to design the operation of the hydraulic system of the walking mechanism of an excavator-dragline and determine the speed of movement of the walking mechanism at each moment of time throughout the entire step. Keywords: hydraulic drive, dragline excavator, threebearing walking mechanism, differential equations in the Cauchy form, design. [email protected]

γ-Selective C(sp3)–H amination via controlled migratory hydroamination

Remote functionalization of alkenes via chain walking has generally been limited to C(sp3)–H bonds α and β to polar-functional units, while γ-C(sp3)–H functionalization through controlled alkene transposition is a longstanding challenge. Herein, we describe NiH-catalyzed migratory formal hydroamination of alkenyl amides achieved via chelation-assisted control, whereby various amino groups are installed at the γ-position of aliphatic chains. By tuning olefin isomerization and migratory hydroamination through ligand and directing group optimization, γ-selective amination can be achieved via stabilization of a 6-membered nickellacycle by an 8-aminoquinoline directing group and subsequent interception by an aminating reagent. A range of amines can be installed at the γ-C(sp3)–H bond of unactivated alkenes with varying alkyl chain lengths, enabling late-stage access to value-added γ-aminated products. Moreover, by employing picolinamide-coupled alkene substrates, this approach is further extended to δ-selective amination. The chain-walking mechanism and pathway selectivity are investigated by experimental and computational methods.

ON THE ACCURACY OF POSITIONING OF MOBILE ROBOT'S WALKING PROPULSION DEVICES

The problems of the influence of the choice of the kinematic scheme of the walking mechanism on the positioning accuracy of its foot with the same small positioning errors are considered. The relationships between the laws of changing the coordinates of the foot of the walking mechanism as a material point and the change in the position of the output elements of the motors of the drives of the orthogonal mover and the mover with a parallel chain of drives are established.

Design and Research of Intelligent Safety Monitoring Robot for Coal Mine Shaft Construction

This study analyzes the main causes of accidents in the period of coal mine shaft construction and the shortage of the existing safety monitoring technology, puts forward the intelligent safety monitoring robot technology based on shaft construction, and deeply investigates the functions that the safety monitoring robot should have. Besides, the research objective of intelligent safety monitoring robot for shaft construction is pointed out, and the research is carried out from such aspects as the robot body structure, walking mechanism, adsorption mechanism, control, communication, intelligent sensing, hazard source recognition, recognition of explosive detonators, and software platform development. As well, this study designs the technical device of intelligent safety monitoring robot for shaft construction, defines the characteristics of this technology, expounds the important significance of studying this technology, and indicates the development trend of this technology.