System and method for rim shape determination

Patent metadata

Field	Value
Publication number	US-10733795-B2
Application number	US-201916243311-A
Country	US
Kind code	B2
Filing date	Jan 9, 2019
Priority date	Jan 10, 2018
Publication date	Aug 4, 2020
Grant date	Aug 4, 2020

Abstract

A system for determining rim shape includes a memory and a processor in communication with the memory. The processor is configured to receive one or more specifications for a rim. The processor is also configured to determine a rim depth for the rim based at least in part on the one or more specifications and a pareto front of rim shapes. The processor is also configured to determine a curvature control ratio and an endpoint tangency angle for the rim based at least in part on the rim depth. The processor is further configured to generate a rim shape for the rim based at least in part on the rim depth, the curvature control ratio, and the endpoint tangency angle.

First claim

What is claimed is:

1. A system for determining rim shape, comprising:
a memory; and
a processor in communication with the memory, wherein the processor is configured to:
receive one or more specifications for a rim;
determine a rim depth for the rim based at least in part on the one or more specifications and a pareto front of rim shapes;
determine a curvature control ratio and an endpoint tangency angle for the rim based at least in part on the rim depth; and
generate a rim shape for the rim based at least in part on the rim depth, the curvature control ratio, and the endpoint tangency angle.

2. The system of claim 1 , wherein the one or more specifications comprises a stability value for the rim.

3. The system of claim 1 , wherein the one or more specifications comprises a designation of whether the rim is a tubular rim or a clincher rim.

4. The system of claim 1 , wherein the processor is further configured to:
generate a plurality of rim models;
determine drag forces and stability forces for each of the plurality of rim models; and
define the pareto front of rim shapes to include rim shapes that minimize the drag forces and the stability forces.

5. The system of claim 4 , wherein the plurality of rim models are generated with a computer-aided design (CAD) program.

6. The system of claim 4 , wherein the drag forces and the stability forces are determined with a computational fluid dynamics (CFD) model that includes information from wind tunnel tests.

7. The system of claim 4 , wherein the pareto front covers a range of rim depths from a minimum rim depth to a maximum rim depth.

8. The system of claim 1 , wherein the processor is further configured to define a design space relative to the pareto front, wherein the rim shape is within the design space.

9. The system of claim 1 , wherein to determine the rim depth for the rim, the processor is configured to:
determine a point on the pareto front that satisfies the one or more specifications for the rim; and
identify the rim depth associated with the point on the pareto front.

10. The system of claim 1 , wherein the processor is configured to generate a first relationship between the curvature control ratio and the rim depth and a second relationship between the endpoint tangency angle and the rim depth.

11. The system of claim 10 , wherein the first relationship comprises a plot or an equation.

12. The system of claim 10 , wherein the first relationship and the second relationship are generated based at least in part on the pareto front of rim shapes, and wherein the processor is further configured to determine the curvature control ratio and the endpoint tangency angle for the rim based on the first relationship and the second relationship.

13. The system of claim 1 , wherein to generate the rim shape, the processor is configured to solve for unknowns in rim shape equations based on at least the rim depth, the curvature control ratio, the endpoint tangency value, and a rim width.

14. A method for determining rim shape, comprising:
receiving, by a computing system, one or more specifications for a rim;
determining, by a processor of the computing system, a rim depth for the rim based at least in part on the one or more specifications and a pareto front of rim shapes;
determining, by the processor, a curvature control ratio and an endpoint tangency angle for the rim based at least in part on the rim depth; and
generating, by the processor, a rim shape for the rim based at least in part on the rim depth, the curvature control ratio, and the endpoint tangency angle.

15. The method of claim 14 , further comprising:
generating a plurality of rim models;
determining drag forces and stability forces for each of the plurality of rim models; and
defining the pareto front of rim shapes to include rim shapes that minimize the drag forces and the stability forces.

16. The method of claim 15 , further comprising using a computational fluid dynamics (CFD) model to determine the drag forces and the stability forces, wherein the CFD model includes information from wind tunnel tests.

17. The method of claim 14 , wherein determining the rim depth comprises:
determining a point on the pareto front that satisfies the one or more specifications for the rim; and
identifying the rim depth associated with the point on the pareto front.

18. The method of claim 14 , further comprising generating a relationship between the curvature control ratio and the rim depth, and wherein the curvature control ratio is determined based on the relationship.

19. The method of claim 14 , wherein generating the rim shape includes solving for unknowns in rim shape equations based on at least the rim depth, the curvature control ratio, the endpoint tangency value, and a rim width.

20. The method of claim 19 , further comprising:
incorporating the unknowns into a second degree rim shape equation; and
plotting the second degree rim shape equation to generate the rim shape.

Assignees

• Trek Bicycle Corp

Inventors

• Drehfal Claude
• Suzuki Mio

Classifications

• G06F30/20 Primary

  Design optimisation, verification or simulation (optimisation, verification or simulation of circuit designs G06F30/30) · CPC title

• B60B21/00

  Rims (non-metallic B60B5/00; of high resiliency B60B9/00; capable of carrying more than one tyre B60B11/04; multiple rims on a single wheel body B60B11/06; of multi-part type B60B25/00; metal tyres B60C) · CPC title

• G06F2111/06

  Multi-objective optimisation, e.g. Pareto optimisation using simulated annealing [SA], ant colony algorithms or genetic algorithms [GA] · CPC title

• G06T2210/24

  Fluid dynamics · CPC title

• G06T17/00 Primary

  Three-dimensional [3D] modelling for computer graphics · CPC title