International Journal of Research in Advent Technology, Vol.2, No.8, August 2014 E-ISSN: 2321-9637
Optimization of Operating Power in the Bicycle using Non-circular Chain Ring: Review Prof. Mahesh S. Gorde 1, Prof. Vishal V.Bhoyar2, Prof. Satish B. Chawale3 Prof.Nishant D.Jogi4 Department of Mechanical Engineering, Jawaharlal Darda College of Engineering & tech., Yavatmal 1,2,3,4 1 gordemahesh7@rediffmail.com , vishalsadguru@gmail.com2, satishchawale@gmail.com3 ngjogi@gmail.com4 Abstract: This paper attempts to provide the reader with a complete picture of recent development in the field of optimization of operating power in the bicycle using Non-circular chain ring through a systematic literature review. Since many countries, the bicycle has been introduced as part of the urban transportation system to extend the accessibility of public transportation systems to final destinations. Usage of bicycles can help reduce air pollution produced by fuel combustions and has many advantages compared to other transportation mode . These facts have caused some communities to promote “Bike to Work” movements. Many research are carried out to optimized operating power & increased operating efficiency of the bicycle using Non-circular chain ring. Keywords: Bicycle, circular chainring , Non-circular chainring. 1. INTRODUCTION The bicycle rider undergo heavy physical stress during riding of bicycle. In India, bicycles are one of the most important means of transportation. In the past years, the changes that took place in the design of the bicycle have not been very prominent. Several studies have been carried out on use of eccentric & non-circular chain rings in bicycle. Many researcher focused on improvement of operating efficiency of bicycle using various type of chain rings viz. Q-ring, O symmetric-Harmonic ring, Ovum ring, Ogival ring, LM- super ring , Polchlopek oval ring etc. Most of the studies shows the comparison of any one type of non-circular chain ring with circular chain ring. A literature review has been done on recent developments in the areas of pedal operated bicycle. Photographic view of various Non-circular chain rings as shown in table. O.symetricHarmonic
Q-Ring (Rotor)
Polchlopek oval
Ovum
Ogival
LM-Super
2.
LITERATURE REVIEW Carpes F.P. investigated the three-dimensional (3-D) pedaling kinematics using a noncircular chain ring system and a conventional system. The purpose of this study was to investigate the effects of a noncircular chain ring system design for cycling on the 3-D pedaling kinematics of cyclists new to the system. Statistical significant differences in pedaling kinematics were found between the noncircular chain ring system evaluated and a conventional crank system. As this investigation was carried out on indoor wind-load cycling simulator (Cateye CS 1000, Cateye Co., Japan) the various factor in actual road condition are not consider in it. Gerda S. investigated kinetics and kinematics between circular and two different shapes of non-circular chain rings. With the help 14 cyclists pedaling on 90 rpm, two-minutes cycling trials using three chain rings ranging from circular to ovality of 1.10 and 1.215 has been carried out . A significant increase of tangential pedal forces and hip joint moments were observed. Non-circular chain rings do not evidently seem to enhance performance, but facilitated conditions for muscle activation as well as a reduction of knee joint moments can occur. Rankin J.W developed musculoskeletal model by using SIMM software .As most studies have sought to improve cycling performance by altering various aspects of the pedaling motion using novel crank–pedal mechanisms and non-circular chain rings. However, most designs have been based on empirical data and very few have provided significant improvements in cycling performance. In this research work author developed musculoskeletal model by using SIMM software. Forward dynamic simulation and dynamic optimization were used 44
International Journal of Research in Advent Technology, Vol.2, No.8, August 2014 E-ISSN: 2321-9637 to determined the muscle excitation pattern and chain ring shape that maximized average crank power over the pedaling rate 60,70,90 rpm. Power during isokinetic pedaling conditions. The optimization identified a consistent non-circular chainring shape at pedaling rates of 60, 90 and 120 rpm with an average eccentricity of 1.29 that increased crank power by an average of 2.9% compared to a conventional circular chainring. The purpose of this study was to use a theoretical framework that included a detailed musculoskeletal model driven by individual muscle actuators, forward dynamic simulations and design optimization to determine if cycling performance (i.e., maximal power output) could be improved by optimizing the chainring shape to maximize average crank. Neptune R.R investigated whether neuromuscular quantities were associated with preferred pedaling rate selection during submaximal steady-state cycling from a theoretical perspective using a musculoskeletal model with an optimal control analysis. Specific neuromuscular quantities of interest were the individual muscle activation, force, stress and endurance. To achieve this objective, a forward dynamic model of cycling and optimization framework were used to simulate pedaling at three different rates of 75, 90 and 105 rpm at 265 W. The pedaling simulations were produced by optimizing the individual muscle excitation timing and magnitude to reproduce experimentally collected data. The results from these pedaling simulations indicated that all neuromuscular quantities were minimized at 90 rpm when summed across muscles. In the context of endurance cycling, these results suggest that minimizing neuromuscular fatigue is an important mechanism in pedaling rate selection. A second objective was to determine whether any of these quantities could be used to predict the preferred pedaling rate. By using the quantities with the strongest quadratic trends as the performance criterion to be minimized in an optimal control analysis, these quantities were analyzed to assess whether they could be further minimized at 90 rpm and produce normal pedaling mechanics. The results showed that both the integrated muscle activation and average endurance summed across all muscles could be further minimized at 90 rpm indicating that these . quantities cannot be used individually to predict preferred pedaling rates Belen L. proposed a new PC prototype chain ring (non-circular) and theoretically it was found that it is more efficient than conventional circular chain ring .The main feature of the PC is that crank-arm alignment and lever-arm length change as a function of the crank angle during the pedaling cycle. The PC presents two features theorized to effect cycling performance, first one out of line of pedal cranks resulting in an decrease in the dead points, and second a change in crank arm length inducing
a torque different from that of conventional chain rings during the down- and up-stroke of the pedaling cycle. To investigate this theory, author examined eight male cyclists who performed a 1-km ‘‘all-out’’ cycling test in the following order: SC, PC, and SC. Performance was measured as the time (s) to complete the 1-km test. Mechanical variables included torque (N m_1), crank velocity (rads_1), and power output (W). They performed statistical analysis using a two-way ANOVA for repeated measurements and Newman–Keuls post hoc assessment. And the results shows that performance was similar for SC 69.41 ± 6.69 s) and PC (73.33 ± 4.58 s). Torque, crank velocity, and power output were also similar throughout (P > 0.05). Finally they conclude that despite the theoretically benefits proposed by the inventors the new PC investigated in their study failed to improve cycling performance or mechanical variables during a supramaximal test when compared with SC. Rasmussen J., described the optimization of a bicycle crank mechanism equipped with springs. The purpose of the springs is to cause an even torque development over the crank cycle by elimination of the so-called dead centers of the cycle. The field of virtual prototyping as manifested by technologies such as Computer-Aided Design, Finite Element Methods, and Computational Fluid Dynamics has had a very significant impact on modern product design. Hardly any advanced product today is designed without the use of some sort of computer simulation, and virtually any technical property of products can be analyzed, including strength, vibration, heat conduction, magnetism, flow, acoustics, and light reflection just to mention a few. However, one prominent property of products has been missing from the range of analysis facilities until recently: The mechanical influence of the product on the human body has not been in the range of analysis. This property also often called ergonomics does not seem like a very important addition at first glance. Modak J.P., suggested machine system used human energy achieved by pedalling and stores this energy in a flywheel at an energy-input rate convenient to the pedaller. After storing the maximum possible energy in the flywheel (pedaling time could be 1-2 minutes) the same can be made available for the actuation of any process unit by making available the energy stored in the flywheel through a suitable clutch and torqueamplification if needed. Thus the flywheel will decelerate depending on the actual resisting torque offered by the process. It implies that the pedaller does not pedal while the flywheel is supplying energy to the process-unit. [8] Spicer J.B.,performed experimental study on the efficiency of bicycle chain drives under a variety of operating conditions and to explore the factors that govern chain drive efficiency. The efficiencies of bicycle chain drives was investigated both experimentally and
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International Journal of Research in Advent Technology, Vol.2, No.8, August 2014 E-ISSN: 2321-9637 theoretically to provide quantitative measurements of chain drive efficiency and to present models for power loss. These models for drive losses have been used to interpret experimental results. Assuming that the losses in the chain drive result from friction between contacting components that execute motion relative to one another, there are three significant sources for loss as follows: [1] Inner link bushing and chain pin, [2] Chain line offset, [3] Sprocket tooth, link roller and inner link bushing. Tests of efficiency for the derailleur-type chain drive indicate that the overall efficiencies for the transfer of power from the front drive sprocket to the rear sprocket range from 80.9% to 98.6%. Primary factors affecting the efficiency include the sizes of the sprockets in the drive and the tension in the chain. Experimentally it was found that larger sprockets provide more efficient transfer of power while smaller sprockets proved to be less efficient. In frictional loss models a 2–5% loss difference was measured between the 52–11 and the 52–21 sprocket combinations depending on the drive operating conditions.. Zikiuddin K.S.,discussed the importance of human power from the earliest times to the present and its future scope. As the use of natural fuel is increased due to industrial development, it’s storage going to end. We need to come with alternate source of energy, i.e non conventional energy. Human power credits its importance in search of an alternative source of energy as it fulfills the requirement of renewable source of energy. More effective use of human power can do by using mechanisms. The technology used to transmit human power to the working unit is termed as human powered machine. The appropriate and most effective technology to use human power efficiently is bicycle technology and more scientific effort is needed to increase the efficiency of bicycle. Hue O. compared the circular & non circular (eccentric) chainring operating performance physiologically & biomechanically with 1.05 & 1.38 eccentricity of chainring at outdoor 1- km laboratory test. The eccentrically design chainring was made of two crank arms sliding into each other, with the inside arm fixed on the center of the arm of a circuler chainring and outside arm sliding along the inside and revolving around an elliptical cam.In this design increase crank arm length at the downstroke and decreases it during the upstroke, thus increasing and decreasing the torque. Author conclude that eccentric chainring significantly improved the cycling performance during all-out 1-km test. But all variable parameters were not considered in this study. A.R.Lende ,developed model & simulation of human powered for field data in the course of artificial neural network and also try to developed artificial intelligence. The experimental Independent variables were reduced by evaluating dimensionless pi terms by Buckingham pi theorem and a mathematical equation was
generated by traditional method to predict them experimental findings. The equation is as shown. ω T = 1.288 ( I/RT2)-0.46 (ME)-0.87 (G)0.40. This research is contributes in development of optimal model through artificial neural network which enables to predict experimental results accurately for seen and unseen data. Ohara C.R. described the effects of chainring type (circular vs. the non- circular Rotor Q-Ring) on performance during a 1km time trial and physiological responses over a six week period. Eight competitive male cyclists and triathletes were pre-tested using the original circular chainring. Graded submaximal exercise tests were followed by the 1km time trial with subjects using their own racing bicycle. The circular chainrings were then removed and replaced with Rotor Q-Rings during the intervention period. Subjects trained and raced with this alteration to their bicycles and repeated the submaximal and 1km performance tests for the next four weeks. Posttesting occurred with the original circular chainrings for the final week of testing. Oxygen consumption, carbon dioxide output, heart rate, ventilation, respiratory exchange ratio, and perceived exertion were continuously measured during the submaximal tests. Blood lactate concentration was measured during the last 30 s of each three minute stage. The main findings were 1) Significant increases in performance in the 1km time trial with Rotor Q-Rings compared to circular chainrings. Subjects completed the time trial on average 1.6 seconds faster , increased average speed approximately 0.7 kph , and increased average power approximately 26 watts . 2) During submaximal testing, oxygen consumption and heart rate were significantly lower with Rotor Q-Rings compared to circular chainrings. 3.
CONCLUSION Many research are carried out to optimized operating power & increased operating efficiency of the bicycle using Non-circular chain ring. This paper gives overall review of Optimization of operating power in the Bicycle using Non-circular chain ring. But still noncircular chain ring is not in use because of some practical problem so this area having a lot of scope for research. REFERANCES [1] Carpes F.P. “Cycling with noncircular chainring system changes the three-dimensional kinematics of the lower limbs ” Sports Biomechanics November 2009; 8(4): 275–283. [2] Gerda S. , “Pedal forces, lower limb joint kinematics and kinetics in cycling with circular and non-circular chainring ”, 30 th Annual conference of Biomechanics in sports – Melbourne 2012. [3] Rankin J.W.,”A theoretical analysis of an optimal chainring shape to maximize crank power during
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International Journal of Research in Advent Technology, Vol.2, No.8, August 2014 E-ISSN: 2321-9637 isokinetic pedaling” Elsevier Science, Journal of Biomechanics 41(2008) p.p.1494-1509. [4] Neptune R.R.,” A theoretical analysis of preferred pedaling rate selection in endurance cycling ”, Elsevier Science, Journal of Biomechanics 32 (1999) 409-415. [5]Belen L.” Cycling performance and mechanical variables using a new prototype chainring” Springerverlag,007,2007. [6]Rasmussen J., “Ergonomic optimization of a springloaded bicycle crank”, 6th World Congresses of Structural and Multidisciplinary Optimization Rio de Janeiro, 30 May - 03 June 2005, Brazil. [7] Modak J.P., “ Design and development of a humanpowered machine for the manufacture of lime-flyashsandbricks ” Human Power, technical journal of the IHPVA, vol.13, No-2,1998. [8] Spicer J.B., “Effect of Frictional loss on Bicycle chain drive efficiency” Biomechanics in Sport, ASME , vol .23, 2001, 598-605. [9] Zikiuddin K.S., “ Human Power: An Earliest Source of Energy and Its Efficient use ” IJSSBT, vol.1,March 2012, 67-69. [10] Hue O. ,”Enhancing cycling performance using an eccentric chainring ” Med. Sci. sports Exerc. Vol.33, No.6,2001. [11] A.R.Lende, “ Modelling & Simulation of Human Powered Flywheel Motor For Field Data in the course of Artificial Neural Network- A Step forward in the development of Artificial Intelligence” IJRET, vol. 02,issue12 ,Dec.2013. [12] Ohara C.R. , “Effects of Chainring Type (Circular vs. Rotor Q-Ring) on 1km Time Trial Performance Over Six Weeks in Competitive Cyclists and Triathletes” International Journal of Sports Science and Engineering Vol. 06 (2012) No. 01, pp. 025-040. [13] Gonzalcez H., “Multivariable Optimization of Cycling Biomechanics”, J. Biomechanics vol.22, No.11, 1989,Great Britain. [14] Zhongxia X. , “Optimal Design of Bicycle Frame Parameters Considering Biomechanics”, Chinese Journal of Mechanical Engineering, Vol. 24, 2011 . [15] J. P. Modak, "Human Powered Flywheel Motor, Concept, Design & Applications" D.Sc (Engg. & Tech.) Thesis being submitted to Nagpur University, Dec. 2007.
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