Bicycle Pedals Research Articles

Evaluation of four-bar mechanisms for bicycle pedals

As the Global Warming destroys gradually the life on the earth, vehicles driven by clean energy are of importance. Therefore, in this paper, mechanisms for bicycle drivetrain are scrutinized starting from its initial invention to attract attentions of the people in the field of mechanism. Some recent health problems caused by design of modern bicycles are highlighted. Optional several mechanisms such as crank rocker, double crank, double rocker, slider crank, and inverted slider crank for the drivetrain of bicycle are evaluated. Each of them was assessed in the perspective of applicability by using shelf-ready products. A double-rocker mechanism is schematically designed by using GeoGebra. An analysis for the geometric constraints of the design and torque are presented. Finally, the double rocker was concluded to design a pedal drivetrain. An optimization was carried out by using Microsoft Excel. The optimal dimensions were delivered. The maximum torque 90 Nm. The maximum energy can be produced is 600W.

Comparative study on the efficiency of motor rehabilitation of the lower limbs using a stationary horizontal bicycle versus a standard therapeutic program

Abstract: The purpose of the present study is to compare the efficiency of two physiother-apeutic programs for rehabilitation of the lower limbs, one using a stationary bicycle and the other one being a standard program, targeting muscle imbalance deficit. Subjects are outpatients - the control group (C n=5), 58.67 ± 11.67 years, received a standard rehabilita-tion program, and the experimental group (E n=5), 56.67 ± 12.14 years, received a pro-posed rehabilitation program implying a stationary bicycle. Equipment used is for muscle imbalances – sensor attached to bicycle pedals, for joint testing – goniometer, for heart rate smart watch, pain assessment – VAS numeric scale, and for perceived effort Borg scale. The rehabilitation program including the stationary horizontal bicycle obtained better re-sults in terms of pain control (T-Test p C/E=.004/.001 and Wilcoxon p C/E=.039/.041) and the correction of muscular imbalances (T-Test p C/E=.003/.000, r= .990/.997) related to the lower limbs, with the mention that both programs recorded statistically significant results regarding functionality. HR values for the control group and experimental group < THR values, aerobic conditioning with the submaximal effort being essential for rehabilitation. Both programs maintained the same perceived level of effort with an average of 3.6 Borg- moderate effort, respectively mild-moderate dyspnea. Keywords: rehabilitation; lower limbs; stationary bicycle; muscle imbalance; pedal sensor; ana-log value; heart rate (HR); target heart rate (THR).

Designing a pedal-operated diaphragm pump and assessing its performance

This research study presents the design and construction of a pedal-operated water pump that may be put to use in a variety of contexts, including garden irrigation, small-scale agriculture, and the removal of water from a reservoir. The pump that is controlled by pedalling may be constructed using just the resources and know-how available locally.  The water pumping apparatus consists of a centrifugal pump that may be powered by foot pedals.  The housing that the foot pedal and the rotating drive shaft will be linked to on the pump stand is included in the pump stand. It works according to the idea of compressing a tube and then suddenly releasing it. This creates a negative pressure within the tube, which in turn creates a vacuum that sucks water from the sump.  This pump, which is controlled by a bicycle's pedals, can extract water from wells and boreholes that are up to 23 feet deep at a rate of 25 to 30 litres per minute. Irrigation and drinking water are provided by it in areas where there is no access to power. It is possible to construct it using materials that are readily accessible in the area, and it is easy to modify it so that it meets the requirements of the people living there. The user saves money on ever-increasing energy expenses, it can be used anywhere, it does not cause pollution, and it provides a good kind of exercise.

Fatigue life analysis of steel bicycle frame according to ISO 4210

The study estimates the fatigue life of a bicycle frame after fatigue failure due to the operational loads. Mechanical properties were determined for a tubular frame made of 25CrMo4 steel. High-cycle fatigue tests were carried out for mini-specimens taken from the location of fatigue failure (joint material) and the base material. The experimental data were compared using a normal distribution for the S-N area and an analysis of the slopes for linear regressions for two data populations. The bicycle frame was evaluated using a fatigue strength approach and nominal stress values. The conditions of the analysis conformed to the safety requirements laid down in the international ISO 4210 standard. The stress was calculated using a finite element model consisting of the surface elements. The highest stress points were selected to compare different fatigue evaluations. The FEA and material data results were compared using a probabilistic Weibull model (P-S-N curve). A mean stress effect was allowed for using the Walker model. The highly stressed volume model and weakest link theory model were used to analyse the size effect. The fatigue life was estimated for the maximum stress determined using FEA. The maximum stress point corresponds to the fatigue failure location on the bicycle frame. The fatigue life at 10% failure probability is below the value recommended in accordance with ISO 4210. A key factor affecting the results is the operating conditions, including the angle of force applied to the bicycle pedals.

Role of tool rotational speed on the tribological characteristics of magnesium based AZ61A/TiC composite developed via friction stir processing route

Purpose: A new composite material was prepared and Different properties such as hardness and tribological behaviour of the fabricated metal matrix composite (MMC) was investigated and compared with the base AZ61A magnesium alloy. Design/methodology/approach: For the current research work, state-of-the-art technology, Friction stir processing (FSP) was performed to develop magnesium based AZ61A/TiC composite at optimized set of machine parameters. Findings: Increasing tool rotational speed ultimately leads in enhanced hardness, which further gives superior tribological properties as compared to base AZ61A alloy. Wear observations suggests a combination of abrasive and adhesive wear mechanism. Research limitations/implications: More microstructural and mechanical properties can be examined. Practical implications: The idea behind selecting AZ61A is mainly due to its increasing use in bicycle pedals and military equipment’s where at certain places it needs to encounter friction. In this current work, microhardness study and wear behaviour of AZ61A/TiC composite processed via FSP were examined. Originality/value: Paper is completely new and no work has been done till date considering this material and preparing composite with nanoparticles TiC.

The Possibility of Noticing the Cyclists Based on Reflective Effect of the Elements on the Bicycle Pedals

The article presents the results of the research describing the changes of bicycle pedal angle relative to the ground, depending on the bicycle crank setting, and the impact of these parameters on detecting the reflective effect emitted by the reflective elements mounted on the bicycle pedals. The results of the road tests determining the cyclist detecting by a car driver, when bicycle is equipped only with bicycle pedals, reflective lights, illuminated with car′s passing lights are also presented. The research described in this article has been carried out for the purpose of reviewing the causes of traffic accidents, occurring at night, in the areas not illuminated by the street lights, in which the cyclists using defective bicycles (according to the regulations) took part.

Effect of telestroke on emergent stroke care and stroke outcomes.

The delivery of medical care through telecommunication has been available in one form or another for ≈100 years. In the early 1900s, people living in remote areas of Australia used 2-way radios (powered by dynamos and bicycle pedals) to communicate with the Australian Royal Flying Doctor Service. The first direct reference to telemedicine in the literature was in the 1950s, with the transmission of radiological images by telephone in Philadelphia, closely followed by the teleradiology system established in Montreal, Canada.1 Telemedicine by video communication was first implemented by the University of Nebraska in the 1960s to allow clinicians to service remote populations.1 Jumping forward to the 21st century, there are now ≥55 telestroke programs in 27 states of the United States that deliver stroke services to ≥350 spoke hospitals.2 To justify the use of telestroke, there is a need for evidence of benefit. However, evaluating the outcomes of a telestroke program is complex because clinical outcomes from treating patients with acute stroke and wider health system and financial metrics need to be captured. The purpose of this review is to provide an overview of the various outcomes of stroke telemedicine and to outline the new paradigms evolving for systems of care, research, and education, as well as financial considerations. Stroke telemedicine (or telestroke) is the practice of clinical stroke care via telecommunication and came into its own with the era of stroke thrombolysis in the late 1990s. A key driver was to ensure better equity for patients in accessing this time-critical therapy in metropolitan and rural hospitals. Our knowledge base on the benefits of stroke thrombolysis continues to develop. The totality of evidence through pooled data analysis indicates that the therapeutic benefit of recombinant tissue-type plasminogen activator (tPA) is time dependent and is greatest when given early …

Optimal Process Conditions for the Manufacture of Aluminum Alloy Bicycle Pedals

Numerous forms and manufacturing methods of bicycle pedals exist in current markets. The purpose of this study was primarily to design an innovative forging die for a bicycle pedal company through a simulative analysis, using commercial finite element package software. A series of simulation analyses adopted workpiece temperature, mold temperature, forging speed, friction factor, and size of the mold as variables to evaluate the methods of lightweight in the bicycle pedal forging press. The study involved modifying professional bicycle pedal sizes. The effective strain, effective stress, and die radius load distribution of the pedals were analyzed under various forging conditions. Aluminum (A6061 and A7075) was used to analyze the simulative data. The optimal control parameters were subsequently obtained using the Taguchi methods and a genetic algorithm. The results of the simulation analyses indicated that the design of an experimental forging die can lower the deformation behavior of a bicycle pedal.

B-9 2軸ロードセルを用いた自転車競技における関節トルク評価(サイクリング2ほか)

In this study, evaluation method of joint torques during cycling were investigated. Newly designed cleat-sized biaxial load cells and an analytical system using a link model and a free body diagram of the lower limbs were developed. The biaxial load cells, which are made with stainless steel, were attached to the bottom of cycling shoes in place of plastic cleats. Any cyclists were able to use their own bicycle, cycling shoes and bicycle pedals with the load cells which were almost same size to plastic cleats (Shimano Corp). The load cells measure the magnitude and direction of right and left pedal force using a total of 16 strain gauges (8 gauges for vertical load and 8 gauges for horizontal load) in each load cell. This analytical system uses the link model of human limbs to identify the positions and angles of each segment of the lower limbs. The free body diagram of the lower limbs consists of 3 segments: thigh, shank and foot. The positions of each lower limb segment, joint torques and forces can be calculated using this system. Here, the relationship between ankle angle and crank angle were analyzed with this system using image-analysis software (TEMA 3D) with a high-speed camera (Photron FASTCAM SA4). This cycling power analysis and optimization system was applied to beginner and well-trained cyclists to investigate the applicability of our system.

Visualization of Pedaling Technique Using Cleat-size Biaxial Load Cells

A visualization system for cycling pedaling technique is investigated in this paper. This system consists of the visualization of pedaling effectiveness and pedaling force vectors. Pedaling effectiveness is defined as the ratio of the tangential to total force applied to the pedals. New biaxial load cells were also developed to attach to the bottom of cycling shoes in place of plastic cleats. These load cells can be connected to the bicycle pedals to measure the magnitude and direction of pedaling forces of both pedals, respectively. The size of load cells is comparable with detachable plastic cleats (Shimano Corp). Therefore, cyclists were permitted to use their own bicycles for performance tests. For visualization of pedaling effectiveness, each force measured by the load cell was converted to coordinates respective to the tangential and radial directions of each crank. The crank angle was calculated from the signal of a magnetic transducer. The pedal angle was calculated using a link mechanism with the lower limbs: the length of the lower limbs, the length of the crank and the position of the greater trochanter were used as constant parameters for computational calculations. For visualization, the relationship between crank angle and force vectors was plotted on a computer, just after the performance tests. This information would be provided for coaches and cyclists in order to identify improvement points for pedaling technique.

Study of Forging Forming of 7075 Aluminum Alloy Bicycle Pedal

Forging is simple and inexpensive in mass production. Metallic materials are processed through plastic deformation. This not only changes the appearance but also changes the internal organization of materials that improve mechanical properties. However, regarding manufacturing of plastic products, many processing factors must be controlled to obtain the required plastic strain and desired tolerance values. In this paper, we employed rigid-plastic finite element (FE) DEFORMTM software to investigate the plastic deformation behavior of an aluminum alloy (A7075) workpiece as it used to forge bicycle pedals. First we use Solid works 2010 3D graphics software to design the bicycle pedal of the mold and appearance, moreover import finite element (FE) DEFORMTM 3D software for analysis. The paper used rigid-plastic model analytical methods, and assuming mode to be rigid body. A series of simulation analyses in which the variables depend on different temperatures of the forging billet, round radius size of ram, punch speed, and mold temperature were revealed to confirm the predicted aluminum grain structure, effective stress, effective strain, and die radial load distribution for forging a bicycle pedal. The analysis results can provide references for forming bicycle pedal molds. Finally, this study identified the finite element results for high-strength design suitability of a 7075 aluminum alloy bicycle pedal.

The effect of Q Factor on gross mechanical efficiency and muscular activation in cycling

Unexplored in scientific literature, Q Factor describes the horizontal width between bicycle pedals and determines where the foot is laterally positioned throughout the pedal stroke. The aim of the study was to determine whether changing Q Factor has a beneficial effect upon cycling efficiency and muscular activation. A total of 24 trained cyclists (11 men, 13 women; VO2max 57.5 ml·kg/min ± 6.1) pedaled at 60% of peak power output for 5 min at 90 rpm using Q Factors of 90, 120, 150, and 180 mm. Power output and gas were collected and muscular activity of the gastrocnemius medialis (GM), tibialis anterior (TA), vastus medialis (VM), and vastus lateralis (VL) measured using surface electromyography. There was a significant increase (P < 0.006) in gross mechanical efficiency (GME) for 90 and 120 mm (both 19.38%) compared with 150 and 180 mm (19.09% and 19.05%), representing an increase in external mechanical work performed of approximately 4-5 W (1.5-2.0%) at submaximal power outputs. There was no significant difference in the level of activity or timing of activation of the GM, TA, VM, and VL between Q Factors. Other muscles used in cycling, and possibly an improved application of force during the pedal stroke may play a role in the observed increase in GME with narrower Q Factors.

Effects of Shoe Cleat Position on Physiology and Performance of Competitive Cyclists

Aerobic economy is an important factor that affects the performance of competitive cyclists. It has been suggested that placing the foot more anteriorly on the bicycle pedals may improve economy over the traditional foot position by improving pedaling efficiency. The current study examines the effects of changing the anterior-posterior pedal foot position on the physiology and performance of well-trained cyclists. In a crossover study, 10 competitive cyclists completed two maximal incremental and two submaximal tests in either their preferred (control) or a forward (arch) foot position. Maximum oxygen consumption and peak power output were determined from the incremental tests for both foot positions. On two further occasions, cyclists also completed a two-part 60-min submaximal test that required them to maintain a constant power output (equivalent to 60% of their incremental peak power) for 30 min, during which respiratory and blood lactate samples were taken at predetermined intervals. Thereafter, subjects completed a 30-min self-paced maximal effort time trial. Relative to the control, the mean changes (+/-90% confidence limits) in the arch condition were as follows: maximum oxygen consumption, -0.5% (+/-2.0%); incremental peak power output, -0.8% (+/-1.3%); steady-state oxygen consumption at 60%, -2.4% (+/-1.1%); steady-state heart rate 60%, 0.4% (+/-1.7%); lactate concentration 60%, 8.7% (+/-14.4%); and mean time trial power, -1.5% (+/-2.9%). We conclude that there was no substantial physiological or performance advantage in this group using an arch-cleat shoe position in comparison with a cyclist's normal preferred condition.

Simplification of Jaw crusher for Artisanal Aggregates Miners

A small-scale mobile jaw-crusher unit with a throughput of 1-1.5 tons of aggregates per hour has been designed, manufactured and tested at the Department of Chemical and Processing Engineering, University of Dar es Salaam. The equipment is aimed at reducing the drudgery and hardships faced by artisanal miners, mostly women, who spend long hours in quarrying sites excavating and crushing aggregates using manual tools. The aim was to design a low-cost unit powered by bicycle pedals however this objective was defeated by economic constraints like labor cost and product price, as well as, technical limitation of the human physique and stamina to sustain pedaling of heavy inertial flywheels required to overcome the actual load and intermittent shock-loads. Instead a simple air-cooled engine 2.94 kW was used causing a 25% increase in investment cost but had 6 fold improvement in productivity over bicycle power and 30 fold boost over manual tools like sledge hammer, pickaxe and crowbars previously used by miners. The crusher was successfully field tested for 3 months by Umoja ni Nguvu women group at Kunduchi Mtongani quarry site to crush 6-8” limestone rocks to aggregates of various sizes ½”, ¾” and 1” required for road and building construction of roads on the outskirts of Dar es Salaam city. Based on the field data and an investment cost of Tshe 3.5 million, a financial profitability analysis indicated that the crusher project has a daily net-inflow of Tshs 259 thousand and a pay-back period of two months. Since the unit requires low level of technical skills and is not capital intensive it is recommended for micro- and medium scale aggregates miners and can be deployed in peri-urban quarries or remote villages without electricity grid. Key words: Jaw-crusher, size reduction, power requirement, small-scale mining.

Instrumented bicycle pedals for dynamic measurement of propulsive cycling loads

A system was developed for measuring and analyzing the forces placed on a bicycle pedal during operation of a stationary ergometer. Forces are measured in the plane parallel to the ergometer in directions normal and tangential to the surface of the pedals, encompassing the plane of propulsive forces. The pedals are designed to be structurally and functionally equivalent to standard clipless pedals. The stock pedal spindle and bearing assembly was replaced with a new spindle that was instrumented with two Wheatstone bridges of foil strain gauges. The bearings were relocated to the crank-arm/pedal-spindle interface. The original pedal body was then pinned to the new spindle. Additionally, the pedals were instrumented with optical encoders to measure the pedal angle relative to the crank arm. An optical encoder was also mounted near the bottom bracket to measure crank-arm angle. Signals were transmitted via a cable tethered to the cyclist’s leg from the pedals to an instrumented chassis, where the strain gauge signals were conditioned and the digital optical encoder signals converted to analogue signals. From the instrumented chassis, seven signals are ready for standard analogue data collection. Data collected from this new system has proved to be both comparable with previously published literature and accurate when compared with expected power output values.

Pedal and knee loads using a multi-degree-of-freedom pedal platform in cycling

To provide a scientific basis for the design of bicycle pedals which possibly alleviate over-use knee injuries, two hypotheses were tested in the present study. The two hypotheses were: (1) that the three-dimensional pedal constraint loads; and (2) that the three-dimensional intersegmental knee loads would be reduced more significantly by a foot/pedal platform allowing both adduction/abduction and inversion/eversion rotations simultaneously than by a platform which allowed either rotation individually. To test these hypotheses, pedal load and lower limb kinematic data were collected from 10 subjects who pedaled with four pedal platforms which allowed zero, one, and two degrees of freedom. A number of quantities describing both pedal loads and intersegmental knee loads was computed for each of the four pedal platforms using a previously reported biomechanical model. The quantities included the positive and negative extremes, averages, and areas, as well as the total absolute area and RMS. Quantities were compared using analysis of variance techniques. The key results were that there were significant reductions in the coupled nondriving moments at the pedal for the dual-rotation platform compared to each of the single-rotation cases. The significant reductions in the coupled moments at the pedal were not manifest at the knee. However, a general nonsignificant reduction in both coupled knee moments was evident. Also, the valgus knee moment was significantly reduced by the dual-rotation platform compared to the inversion/eversion only design. Although the axial knee moment was not significantly reduced by the dual-rotation platform over the adduction/abduction design, there was a general nonsignificant reduction. The lack of significance in knee load results occurred because of high intersubject variability. Accordingly, load reduction benefits made by introducing the second degree of freedom need to be considered individually.

Aging and stress-induced changes in complement activation and neutrophil mobilization

We measured the extent of complement activation and neutrophil mobilization after eccentric exercise to determine whether these responses were age dependent and whether they were associated with changes in plasma creatine kinase (CK), a marker for muscle membrane integrity. Repeated forced lengthening of a muscle as it develops tension causes immediate ultrastructural damage to sarcomeres, followed by delayed-onset muscle soreness and release of myocellular enzymes. This can be accomplished in quadriceps muscles by running downhill or by resisting bicycle pedals driven backward by a motor. Twelve older (61-72 yr) and 9 younger (20-32 yr) subjects performed one of these activities for 45 min at an intensity of 78 +/- 2% of maximum heart rate. For all subjects, a median increase of 21% in plasma des-Arg-C3a levels occurred immediately after the protocol, circulating neutrophils increased 66 +/- 10% by 4-6 h, and plasma CK increased 135 +/- 25% by 24 h. The peak increases in neutrophils correlated with the peak increases in des-Arg-C3a (rho = 0.662, P = 0.006), and the peak increases in CK correlated with the rise in neutrophils (rho = 0.523, P = 0.027). The increases in neutrophils and plasma CK were significantly smaller in the older subjects (P < 0.05). The results indicate that increased concentrations of circulating CK after muscle injury are associated with a sequential cascade of inflammatory mediators. Furthermore, neutrophil mobilization, but not complement activation, was diminished in older subjects in response to this stress.

A Dual Piezoelectric Bicycle Pedal with Multiple Shoe/Pedal Interface Compatibility

In response to the popularity of clipless bicycle pedals with float designs, an instrumented force pedal system with multicompatibility for different shoe/pedal interfaces is presented. A dual piezoelectric element pedal has been modified for use with popular clipless pedal interfaces. The dual transducer arrangement permits measurement of three components of uniaxial load, location of the applied load, and calculation of the moment Mz about an axis through the position of the applied load and orthogonal to the pedal surface. Quantification of lower extremity kinetics using float feature pedals and the investigation of the pathomechanics of lower extremity cycling overuse injuries, especially knee injuries, is warranted. Qualitative descriptions of lower extremity pathomechanics related to overuse injuries have suggested that foot constraint may induce undesirable knee kinematics and kinetics. The instrumented force pedal system described here permits a comparison between pedal kinematics and kinetics of popular shoe/pedal interfaces with varying degrees of float allowance.

Bicycle pedal modifications for use in a physical therapy department.

Riding a bicycle ergometer is often included as part of the physical therapy rehabilitation program for patients with weakness in the lower extremities or for patients who need to improve their cardiovascular fitness. Some patients are unable to hold their feet on the bicycle pedals, however, because of their particular medical problems such as stroke, head trauma, or extreme weakness. In some cases, toe clips have been used successfully to solve this problem, but for many patients even these are not satisfactory. This is particularly true if the patient cannot be relied upon to keep his feet in the clips, because he could be injured if his feet slipped off the pedals. One way to remedy this problem is to attach a cast boot to a block of wood that has been cut to accommodate the bicycle pedal.…

A head-out exercise body plethysmograph.

A head-out exercise body plethysmograph has been developed to facilitate investigations of the extrathoracic airways. An airtight seal around the neck is provided by a pliable sheet of dental dam braced by a tubular bean bag. A set of bicycle pedals is connected by a chain drive, axle, and wall-mounted sealed ball bearing to an external ergometer. The box is air-conditioned to allow exercise up to work loads of 200 W with a temperature increase of less than 1 degree C above ambient laboratory readings. Nose, mouth, and extrathoracic airways are easily accessible for airflow and pressure measurements. O2, CO2, and humidity levels of respired air are not disturbed, verbal communication with the subject is possible, and the subject is unlikely to feel claustrophobic. The plethysmograph has a flat frequency response to 4.2 Hz; it thus functions accurately in both resting and exercise measurements of respiratory minute ventilation. The plethysmograph can also be used for determinations of nasal and oral airflow and pressure, and the study of breathing patterns.