Novel Innovation Design for Increasing Power Machine Using Mechanical Advantage Flywheel

Author(s):  
Natin Janjamraj ◽  
Buabutsara Akarasarutipong
Author(s):  
Brendan L Pinto ◽  
Clark R Dickerson

Employing an arched back posture during the bench press exercise is increasingly popular. Vertical displacement of the barbell is commonly believed to be the key difference influencing strength performance between an arched and flat back bench press technique. However, comparisons between these back postures using a free weight barbell are lacking. Directly comparing performance between each posture is confounded by many variables such as proficiency and fatigue. This investigation aimed to investigate whether changing back posture alone can influence barbell kinematics, to indirectly assess potential performance differences. Twenty males performed one repetition of the bench press exercise using either an arched or flat back posture, at 25%, 50% and 75% of their one repetition maximum, in a repeated measures study design. Statistical significance was considered at p < 0.05. Changing back posture alone, reduced vertical displacement (approximately 11% average difference across all load conditions) and barbell to glenohumeral joint moment arm (approximately 20% difference) in the arched posture compared to the flat posture. These changes occurred without any specific cueing of the barbell motion and may increase the potential for lifting higher loads and decrease cumulative joint exposure. Additional cueing and training may be required to maximize the mechanical advantage available with each back posture. The arched posture appears to have an increased potential for further improvements in vertical displacement and moment arm through specific cueing. Future comparisons should consider if each back posture’s potential mechanical advantage has been maximized when assessing differences between techniques.


Machines ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 32
Author(s):  
Viktor Shcherba ◽  
Viktor Shalay ◽  
Evgeniy Nosov ◽  
Evgeniy Pavlyuchenko ◽  
Ablai-Khan Tegzhanov

This article considers the development and research of a new design of crosshead-free piston hybrid power machine. After verification of a system of simplifying assumptions based on the fundamental laws of energy, mass, and motion conservation, as well as using the equation of state, mathematical models of the work processes of the compressor section, pump section, and liquid flow in a groove seal have been developed. In accordance with the patent for the invention, a prototype of a crosshead-free piston hybrid power machine (PHPM) was developed; it was equipped with the necessary measuring equipment and a stand for studying the prototype. Using the developed mathematical model, the physical picture of the ongoing work processes in the compressor and pump sections is considered, taking into account their interaction through a groove seal. Using the developed plan, a set of experimental studies was carried out with the main operational parameters of the crosshead-free PHPM: operating processes, temperature of the cylinder–piston group and integral parameters (supply coefficient of the compressor section, volumetric efficiency of the pump section, etc.). As a result of numerical and experimental studies, it was determined that this PHPM design has better cooling of the compressor section (decrease in temperature of the valve plate is from 10 to 15 K; decrease in temperature of intake air is from 6 to 8 K, as well as there is increase in compressor and pump section efficiency up to 5%).


2018 ◽  
Vol 172 ◽  
pp. 03003
Author(s):  
A. Agarwal

In this paper we discussed the new design, fabrication and testing of a mechanical can crusher taking into deliberation the force analysis and ergonomic factors that will enable people to use this mechanical can crusher especially in Botswana rural areas. The process of crushing cans is of vital importance as it saves a percentage of space for can disposal and also makes it easier for these cans to be transported to recycling centers or landfill areas. The methods and processes used to bring this project to life include welding, cutting, bending, drilling and assembly operations. This project study is mainly about generating a new concept of a mechanical can crusher that is compact to transport from one location to another and makes can crushing easy and fascinating to the general public so as to promote people buy into crushing in Sub-Sahara market. Even though there are numerous sorts of the mechanical would crusher be able to as of now in presence, this model provides a more practical usage than previous one with the desired mechanical advantage of 10, machinability to crush the entire cans to 25% of their original size and 100% efficiency for the entire rounds.


Behaviour ◽  
2014 ◽  
Vol 151 (12-13) ◽  
pp. 1663-1686 ◽  
Author(s):  
Kasey D. Fowler-Finn ◽  
Emilia Triana ◽  
Owen G. Miller

When mating interactions are influenced by multiple sources of selection, they may involve multiple stages of mate assessment. At each stage, a different set of morphological and behavioural traits may be important in determining the outcome of the interaction. Here, we test the potential for multiple sources of selection to shape mating interactions in Leiobunum vittatum harvestmen, commonly known as ‘daddy longlegs’. We provide a qualitative and quantitative study of mating interactions, and investigate the influence of multiple morphological traits on each of several distinct stages of their mating interactions. Mating interactions start with a struggle between males and females during which the male attempts to secure the females in a mating embrace. Success at this stage depends on the length of the male’s clasping pedipalps: those with shorter pedipalps (and thus greater mechanical advantage) were more successful. Male size relative to the female determines how quickly males achieve this embrace. Mating interactions then proceed to tactile exchanges between males and females, indicating the potential for mutual mate choice and/or peri- and post-copulatory selection. We found no morphological predictors of the timing of these later stages of the mating interactions, and suggest that the exchange of a nuptial gift is important for the dynamics of these stages. Overall, our results highlight L. vittatum as a potentially highly informative group for studying how traits involved in mating are shaped by the interaction of selection across multiple stages in mating interactions.


2018 ◽  
Vol 302 (5) ◽  
pp. 775-784 ◽  
Author(s):  
Christine M. Harper ◽  
Adam D. Sylvester

Author(s):  
Amos G. Winter ◽  
Mario A. Bollini ◽  
Benjamin M. Judge ◽  
Natasha K. Scolnik ◽  
Harrison F. O’Hanley ◽  
...  

The Leveraged Freedom Chair (LFC) is a low-cost, all-terrain, variable mechanical advantage, lever-propelled wheelchair designed for use in developing countries. The user effectively changes gear by shifting his hands along the levers; grasping near the ends increases torque delivered to the drive-train, while grasping near the pivots enables a larger angular displacement with every stroke, which increases angular velocity in the drivetrain and makes the chair go faster. This paper chronicles the design evolution of the LFC through three user trials in East Africa, Guatemala, and India. Feedback from test subjects was used to refine the chair between trials, resulting in a device 9.1 kg (20 lbs) lighter, 8.9 cm (3.5 in) narrower, and with a center of gravity 12.7 cm (5 in) lower than the first iteration. Survey data substantiated increases in performance after successive iterations. Quantitative biomechanical performance data were also measured during the Guatemala and India trials, which showed the LFC to be 76 percent faster and 41 percent more efficient during a common daily commute and able to produce 51 percent higher peak propulsion force compared to conventional, pushrim-propelled wheelchairs.


2020 ◽  
pp. 256-256
Author(s):  
Yanjun Xiao ◽  
Jing Gao ◽  
Jiamin Ren ◽  
Wei Zhou ◽  
Feng Wan ◽  
...  

Roots power machine has obvious advantages in low and medium temperature waste heat recovery. The existing roots power machine has the problem of internal flow field disturbance, which seriously affects the power generation efficiency of the power machine. In order to solve the problem of disturbance of the internal flow field of roots power machine, the traditional involute rotor roots power machine is improved, and the roots power machine based on negative displacement involute rotor is proposed. The structure model and turbulence model of roots power machine are constructed, and the internal flow field simulation of roots power machine is realized by computational fluid dynamics. The pressure contour and torque change of roots power machine before and after improvement are compared, and the experimental research on the improved structure is carried out. The results show that the intensity of flow field disturbance in the modified involute rotor roots power machine decreases, and the working performance of the roots power machine improves, which provides a reference for the structural improvement and performance optimization of roots power machine.


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