grey/BOSL2
1
0
Fork 0
mirror of https://github.com/BelfrySCAD/BOSL2.git synced 2025-01-01 09:49:45 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

Fixes for gear tooth profiles.

Browse source
This commit is contained in:
Revar Desmera 2023-07-21 00:05:53 -07:00
parent 88c912c9bb
commit 3775149591
1 changed files with 22 additions and 21 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

43
gears.scad
View file

@ -2002,6 +2002,9 @@ function _gear_tooth_profile(
helical = 0,
internal = false,
profile_shift = 0.0,
mod,
diam_pitch,
pitch,
center = false
) = let(
// Calculate a point on the involute curve, by angle.
@ -2009,6 +2012,7 @@ function _gear_tooth_profile(
let(b=a*PI/180) base_r * [cos(a)+b*sin(a), sin(a)-b*cos(a)],
steps = 16,
circ_pitch = circular_pitch(pitch=pitch, circ_pitch=circ_pitch, diam_pitch=diam_pitch, mod=mod),
// Calculate the important circle radii
arad = outer_radius(circ_pitch, teeth, helical=helical, profile_shift=profile_shift, internal=internal),
@ -2072,8 +2076,8 @@ function _gear_tooth_profile(
// The u values to use when generating the tooth.
us = [
for (i=[0:1:20-1]) 0.2*sin(i/20*90),
for (i=[2:1:steps-1]) i/(steps-1),
for (i=[0.0:0.02:0.2-EPSILON]) i,
for (i=[0:1:steps-1]) 0.2 + i/(steps-1)*0.8,
],
// Generate the left half of the tooth.
@ -2089,26 +2093,23 @@ function _gear_tooth_profile(
) polar_to_xy(ma_rad, a),
]),
// Find undercut bottom "jaggie" if it exists.
minima = [
for (i = idx(tooth_half_raw))
let(p = tooth_half_raw[i])
if (i > 0 && i < len(tooth_half_raw)-1 && norm(p) <= prad)
let(
pp = tooth_half_raw[i-1],
np = tooth_half_raw[i+1]
)
if (p.x > pp.x && p.x > np.x)
i
],
// Strip "jaggies" if found.
tooth_half = len(minima)<2? tooth_half_raw : [
for (i = idx(tooth_half_raw))
let(p = tooth_half_raw[i])
if (i <= minima[0] || i >= last(minima))
p
],
strip_left = function(path,i)
i > len(path)? [] :
norm(path[i]) >= prad? [for (j=idx(path)) if(j>=i) path[j]] :
let(
angs = [
for (j=[i+1:1:len(path)-1]) let(
p = path[i],
np = path[j],
r = norm(np),
a = v_theta(np-p)
) if(r<prad) a
],
mti = !angs? 0 : min_index(angs),
out = concat([path[i]], strip_left(path, i + mti + 1))
) out,
tooth_half = strip_left(tooth_half_raw, 0),
// Mirror the tooth to complete it.
tooth = deduplicate([