Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

The Chain Rule01:30

The Chain Rule

295
A system of interconnected gears provides a concrete physical interpretation of the Chain Rule in calculus. Consider three gears arranged in sequence, where the rotational speeds of the first, second, and third gears are represented by the variables x, z, and y, respectively. The first gear drives the second, and the second drives the third, so the motion of each gear depends on the one preceding it. This structure naturally leads to a two-stage variable relationship that can be analyzed using...
295
Design of Transmission Shafts01:16

Design of Transmission Shafts

909
The design of a transmission shaft is governed by two primary specifications: the power it transmits and its rotational speed. These parameters guide the selection of the shaft's material and cross-sectional dimensions, ensuring that the material's maximum shearing stress remains within the elastic limit while transmitting the desired power at the given speed. The system's power is intrinsically linked to the applied torque. The torque applied to the shaft can be calculated by reconfiguring the...
909
Transmission Shafts: Problem Solving01:09

Transmission Shafts: Problem Solving

681
Designing a solid shaft that transmits power from a motor to a machine tool involves a series of calculations to ensure the shaft can withstand the stresses applied by bending moments and torques. First, calculate the torque exerted on the gear, considering the power transmitted by the shaft and its rotational speed. Following this, compute the tangential forces acting on the gears, which directly relate to the torque and the gear radius.
Next, use bending moment diagrams for the shaft to...
681
Radian and Degree Measure01:29

Radian and Degree Measure

986
Angular motion is measured using two primary units: degrees and radians. These units describe the extent of rotation around a fixed point. A complete rotation corresponds to 360 degrees or 2π radians, depending on the unit used. Although both represent the same angular displacement, they differ in origin and application.Degrees divide a circle into 360 equal segments. Due to its intuitive structure, this unit is historically rooted and widely used in general applications such as...
986
The Chain Rule: Problem Solving01:23

The Chain Rule: Problem Solving

191
The thermal expansion of a metal rod shows the application of the Chain Rule when one physical quantity depends on another that varies with time. As the rod is heated, its length changes according to linear thermal expansion, while the temperature of the system varies quadratically with time.For linear thermal expansion, the length L of the rod depends on temperature T such that the rate of change of length with respect to temperature is constant:where L0 = 2 m is the initial length of...
191
Geometric Sequences01:30

Geometric Sequences

400
In systems where values diminish by a constant proportion at each stage, the resulting sequence follows a geometric structure. Each new value in the sequence is obtained by applying a fixed multiplier to the preceding term. This regular, proportional decline type is often used to represent processes involving gradual loss, such as energy dissipation or reduction in amplitude over time.When analyzing the total effect of such a process across unlimited iterations, the series of values is referred...
400

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Muscle-controlled physics simulations of bird locomotion resolve the grounded running paradox.

Science advances·2024
Same author

Towards determination of power loss at a rowing blade: Validation of a new method to estimate blade force characteristics.

PloS one·2019
Same author

Experimental estimation of energy absorption during heel strike in human barefoot walking.

PloS one·2018
Same author

Commentary: Validation of a Ramp Running Protocol for Determination of the True VO<sub>2max</sub> in Mice.

Frontiers in physiology·2017
Same author

Estimation of the energy loss at the blades in rowing: common assumptions revisited.

Journal of sports sciences·2010
Same author

The effect of posture on early reaching movements.

Journal of motor behavior·2009

Related Experiment Video

Updated: May 6, 2026

A Modeling and Simulation Method for Preliminary Design of an Electro-Variable Displacement Pump
09:04

A Modeling and Simulation Method for Preliminary Design of an Electro-Variable Displacement Pump

Published on: June 1, 2022

2.6K

From bicycle chain ring shape to gear ratio: algorithm and examples.

A J van Soest1

  • 1Faculty of Human Movement Sciences, Research Institute MOVE, VU University Amsterdam, van der Boechorststraat 9, 1081 BT Amsterdam, The Netherlands.

Journal of Biomechanics
|November 9, 2013
PubMed
Summary
This summary is machine-generated.

This study introduces a model for bicycle drive systems with non-circular chainrings, calculating Gear Ratio As a Function Of Crank Angle (GRAFOCA). It reveals that the true effective radius differs from common approximations, impacting GRAFOCA predictions.

Keywords:
AlgorithmBicyclingEffective radiusGear ratioNon-circular chain rings

More Related Videos

A Rapid Method for Modeling a Variable Cycle Engine
04:58

A Rapid Method for Modeling a Variable Cycle Engine

Published on: August 13, 2019

7.1K
The TreadWheel: Interval Training Protocol for Gently Induced Exercise in Drosophila melanogaster
07:21

The TreadWheel: Interval Training Protocol for Gently Induced Exercise in Drosophila melanogaster

Published on: June 8, 2018

12.7K

Related Experiment Videos

Last Updated: May 6, 2026

A Modeling and Simulation Method for Preliminary Design of an Electro-Variable Displacement Pump
09:04

A Modeling and Simulation Method for Preliminary Design of an Electro-Variable Displacement Pump

Published on: June 1, 2022

2.6K
A Rapid Method for Modeling a Variable Cycle Engine
04:58

A Rapid Method for Modeling a Variable Cycle Engine

Published on: August 13, 2019

7.1K
The TreadWheel: Interval Training Protocol for Gently Induced Exercise in Drosophila melanogaster
07:21

The TreadWheel: Interval Training Protocol for Gently Induced Exercise in Drosophila melanogaster

Published on: June 8, 2018

12.7K

Area of Science:

  • Mechanical Engineering
  • Bicycle Dynamics
  • Tribology

Background:

  • Bicycle drive systems commonly use circular chainrings.
  • Non-circular chainrings offer potential advantages in power transmission efficiency.
  • Accurate modeling of non-circular chainrings is crucial for performance optimization.

Purpose of the Study:

  • To propose a simple model for bicycle drive systems featuring a non-circular front chainring.
  • To devise an algorithm for calculating the Gear Ratio As a Function Of Crank Angle (GRAFOCA).
  • To compare the true effective radius of a non-circular chainring with commonly used approximations.

Main Methods:

  • Development of a simplified mechanical model for the bicycle drive system.
  • Derivation of an algorithm to compute GRAFOCA.
  • Geometric analysis to determine the true effective radius of the chainring.

Main Results:

  • The true effective radius is defined as the perpendicular distance from the crank axis to the chain segment line.
  • The true effective radius can differ significantly from approximations based on maximum vertical distance.
  • Predicted crank angles for maximum effective radius may deviate by up to 0.30 rad from true values.

Conclusions:

  • The proposed model and algorithm provide a more accurate method for calculating GRAFOCA.
  • Existing approximations for effective chainring radius can lead to substantial errors.
  • The developed algorithm can aid in the design of optimized non-circular chainrings for desired GRAFOCA profiles.