Automated Mechanical Transmission

In order to search after a new way of the propulsion system of tracked vehicle, a novel structure form of electro-mechanical transmission was developed in this paper, through analyzing the advantages and disadvantages of existing projects of electric drive system for tracked vehicle. It could increase the rate of power exertion obviously and synthesize the mechanical and electrical strongpoint. And based on the structure form, an electro-mechanical transmission was designed with double electromotor added planetary mechanism of steering power coupling and gearshift, considering engineering realization. And then straight-line driving and steering performances of the transmission were calculated which proved that the novel electro-mechanical transmission could meet the requirement of tracked vehicle propulsion well.

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Barrier-Free Wheelchair with a Mechanical Transmission

Applied Sciences ◽

10.3390/app11115280 ◽

2021 ◽

Vol 11 (11) ◽

pp. 5280

Author(s):

Jongseok Lee ◽

Wonhyeong Jeong ◽

Jaeoh Han ◽

Taesu Kim ◽

Sehoon Oh

Keyword(s):

The Elderly ◽

Transmission System ◽

Motor Drives ◽

Mechanical Transmission ◽

Link Structure ◽

Second Mode ◽

Important Means ◽

The Stability ◽

Flat Ground ◽

Climbing Stairs

Wheelchairs are an important means of transportation for the elderly and disabled. However, the movement of wheelchairs on long curbs and stairs is restricted. In this study, a wheelchair for climbing stairs was developed based on a mechanical transmission system that rotates the entire driving part through a link structure and an actuator to change the speed. The first mode drives the caterpillar, and the second mode drives the wheels. When driving on flat ground, it uses landing gears and wheels, and when climbing stairs, it uses the caterpillar; accordingly, a stable driving is possible. The stability of the transmission is confirmed through stress analysis. The method used in our study makes it is possible to manufacture lightweight wheelchairs because a single motor drives both the wheel and caterpillar through the transmission system.

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Automated Conceptual Design of Multiple Input and Multiple Output Mechanical Transmission System

2010 Second International Conference on Computer Engineering and Applications ◽

10.1109/iccea.2010.172 ◽

2010 ◽

Cited By ~ 1

Author(s):

He Bin ◽

Lv Hai Feng ◽

Liu Wen Zhen ◽

Han Li Zhi

Keyword(s):

Conceptual Design ◽

Transmission System ◽

Mechanical Transmission ◽

Multiple Input

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Optimization for speed regulation strategy of compound coupled hydro-mechanical transmission

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/0954407020980564 ◽

2020 ◽

pp. 095440702098056

Author(s):

Jin Yu ◽

Pengfei Shen ◽

Zhao Wang ◽

Yurun Song ◽

Xiaohan Dong

Keyword(s):

Fuel Consumption ◽

Dynamic Programming Algorithm ◽

Operating Conditions ◽

Programming Algorithm ◽

Speed Ratio ◽

Mechanical Transmission ◽

Speed Regulation ◽

Ratio Change ◽

Low Efficiency ◽

Wheel Loaders

Heavy duty vehicles, especially special vehicles, including wheel loaders and sprinklers, generally work with drastic changes in load. With the usage of a conventional hydraulic mechanical transmission, they face with these problems such as low efficiency, high fuel consumption and so forth. Some scholars focus on the research to solve these issues. However, few of them take into optimal strategies the fluctuation of speed ratio change, which can also cause a lot of problems. In this study, a novel speed regulation is proposed which cannot only solve problems above but also overcome impact caused by speed ratio change. Initially, based on the former research of the Compound Coupled Hydro-mechanical Transmission (CCHMT), the basic characteristics of CCHMT are analyzed. Besides, to solve these problems, dynamic programming algorithm is utilized to formulate basic speed regulation strategy under specific operating condition. In order to reduce the problem caused by speed ratio change, a new optimization is applied. The results indicate that the proposed DP optimal speed regulation strategy has better performance on reducing fuel consumption by up to 1.16% and 6.66% in driving cycle JN1015 and in ECE R15 working condition individually, as well as smoothing the fluctuation of speed ratio by up to 12.65% and 19.01% in those two driving cycles respectively. The processes determining the speed regulation strategy can provide a new method to formulate the control strategies of CCHMT under different operating conditions particularlly under real-world conditions.

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Parameter Estimation of a Countershaft Brake for Heavy-Duty Vehicles with Automated Mechanical Transmission

Processes ◽

10.3390/pr9061036 ◽

2021 ◽

Vol 9 (6) ◽

pp. 1036

Author(s):

Yunxia Li ◽

Lei Li

Keyword(s):

Parameter Identification ◽

Least Squares ◽

Dynamic Model ◽

Control Flow ◽

Mechanical Transmission ◽

Equivalent Resistance ◽

Heavy Duty ◽

Characteristic Parameters ◽

Resistance Torque ◽

Heavy Duty Vehicles

A countershaft brake is used as a transmission brake (TB) to realize synchronous shifting by reducing the automated mechanical transmission (AMT) input shaft’s speed rapidly. This process is performed to reduce shifting time and improve shifting quality for heavy-duty vehicles equipped with AMT without synchronizer. To improve controlled synchronous shifting, the AMT input shaft’s equivalent resistance torque and the TB’s characteristic parameters are studied. An AMT dynamic model under neutral gear position is analyzed during the synchronous control interval. A dynamic model of the countershaft brake is discussed, and its control flow is given. The parameter identification method of the AMT input shaft’s equivalent resistance torque is given on the basis of the least squares algorithm. The parameter identification of the TB’s characteristic parameters is proposed on the basis of the recursive least squares method (RLSM). Experimental results show that the recursive estimations of the TB’s characteristic parameters under different duty cycles of the TB solenoid valve, including brake torque estimation, estimation accuracy, and braking intensity estimation, can be effectively estimated. The research provides some reliable evidence to further study the synchronous shifting control schedule for heavy-duty vehicles with AMT.

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Developmental competence and antigen switch frequency can be uncoupled in Trypanosoma brucei

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1912711116 ◽

2019 ◽

Vol 116 (45) ◽

pp. 22774-22782 ◽

Cited By ~ 1

Author(s):

Kirsty R. McWilliam ◽

Alasdair Ivens ◽

Liam J. Morrison ◽

Monica R. Mugnier ◽

Keith R. Matthews

Keyword(s):

Trypanosoma Brucei ◽

Antigenic Variation ◽

Experimental Studies ◽

Developmental Competence ◽

Parasite Development ◽

Mammalian Host ◽

Mechanical Transmission ◽

African Trypanosomes ◽

Infection Dynamic ◽

Developmental Capacity

African trypanosomes use an extreme form of antigenic variation to evade host immunity, involving the switching of expressed variant surface glycoproteins by a stochastic and parasite-intrinsic process. Parasite development in the mammalian host is another feature of the infection dynamic, with trypanosomes undergoing quorum sensing (QS)-dependent differentiation between proliferative slender forms and arrested, transmissible, stumpy forms. Longstanding experimental studies have suggested that the frequency of antigenic variation and transmissibility may be linked, antigen switching being higher in developmentally competent, fly-transmissible, parasites (“pleomorphs”) than in serially passaged “monomorphic” lines that cannot transmit through flies. Here, we have directly tested this tenet of the infection dynamic by using 2 experimental systems to reduce pleomorphism. Firstly, lines were generated that inducibly lose developmental capacity through RNAi-mediated silencing of the QS signaling machinery (“inducible monomorphs”). Secondly, de novo lines were derived that have lost the capacity for stumpy formation by serial passage (“selected monomorphs”) and analyzed for their antigenic variation in comparison to isogenic preselected populations. Analysis of both inducible and selected monomorphs has established that antigen switch frequency and developmental capacity are independently selected traits. This generates the potential for diverse infection dynamics in different parasite populations where the rate of antigenic switching and transmission competence are uncoupled. Further, this may support the evolution, maintenance, and spread of important trypanosome variants such as Trypanosoma brucei evansi that exploit mechanical transmission.

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