get_rear_triangle_dims: Get rear triangle dimensions

In ghuiber/bicycle: Design a bicycle frame

Description

The rear triangle is made up of the projection in the horizontal plane of the chain stay, the seat stay, and the seat tube. The seat tube is the same as its projection in the horizontal plane, but the other two tubes stick out at an angle, ans they must accommodate the width of the rear wheel hub, so there's some trigonometry involved.

Usage

get_rear_triangle_dims(
  st_length = 500,
  cs_length = 450,
  st_angle = 71,
  cs_st_angle = 61,
  angle_btw_css = 14
)

Arguments

st_length	The length of the seat tube ST in millimeters.
cs_length	Chain stay length in millimeters.
st_angle	The angle between the seat tube and the horizontal.
cs_st_angle	Angle between chain stay and seat tube, in degrees.
angle_btw_css	Angle between chain stays, in degrees.

Details

A bike frame designer aims for a seat tube length (st_length) that fits a rider of a given height, and also for a seat tube angle (st_angle) and chain stay length (cs_length) that give the bike its desired riding characteristics, though cs_length is subject to some other constraints described in the documentation for get_cs_length().

The angle between the chain stay and the seat tube (cs_st_angle) is pre-determined in lugged frame construction by how the bottom bracket shell was cast.

This function returns the dimensions of the rear triangle using the convention described in the documentation for get_front_triangle_dims().

Value

A 3 x 3 tibble.

See Also

get_cs_length()

get_front_triangle_dims()

Examples

get_rear_triangle_dims()

ghuiber/bicycle documentation built on Dec. 20, 2021, 10:46 a.m.