clarify which sonar sensor the holder is for

[challenge-bot] / 3d-printables / sonar-table-top-holder.scad

diff --git a/3d-printables/sonar-table-top-holder.scad b/3d-printables/sonar-table-top-holder.scad
index d34c694c7c675f18516a3c0c345b81c63cb52878..56d58f9c7af31d61ccc14866d0caf3540dd106ab 100644 (file)
--- a/3d-printables/sonar-table-top-holder.scad
+++ b/3d-printables/sonar-table-top-holder.scad
@@ -4,6 +4,14 @@
 // https://gitorious.org/ozzloy/challenge-bot
 // https://github.com/waynegramlich/challenge-bot
 
+/*
+  this holds an hc-sr04 sonar sensor to a 3/16 inch deck.
+  http://fritzing.org/projects/hc-sr04-project
+  it can hold the sonar sensor either facing down, or forwards.
+  when facing down, it can detect if it passes over the edge of a table.
+  when facing forwards, it can detect and follow something in front of it.
+ */
+
 $fn = 60;
 
 // 3/16 inch in mm deck_depth = 4.7625;
@@ -14,7 +22,7 @@ deck_depth = 4.7625 - 0.4;
 //  10.82 in between, 42.33 outside, 15.82 diameter
 // measured diameter of 15.82 with calipers,
 //  but when printed ends up being too small, so add some
-sonar_diameter = 15.82 + 0.6;
+sonar_diameter = 15.82 + 0.4;
 sonar_radius = sonar_diameter / 2;
 sonar_height = 13.8;
 between_sonar_centers = sonar_diameter + 10.82;
@@ -27,7 +35,7 @@ sonar_holder_length = buffer + between_sonar_centers + sonar_diameter + buffer;
 sonar_holder_width = buffer + sonar_diameter + buffer;
 // sonar_holder_depth is deck_depth minus a little bit to make arm fit
 //  into deck holder
-sonar_holder_depth = deck_depth - 0.8;
+sonar_holder_depth = deck_depth - 0.7875;
 
 deck_holder_length = sonar_holder_depth * 2 + deck_depth + 15;
 
@@ -43,28 +51,27 @@ module sonars(){
     cylinder(r = sonar_radius, h = sonar_height);}}
 
 module sonar_holder(){
-  elbow_length = deck_depth + 0.8;
+  elbow_length = deck_depth - 0.5;
   difference(){
     cube([sonar_holder_length, sonar_holder_width, sonar_holder_depth]);
     translate([sonar_holder_length / 2, sonar_holder_width / 2, -0.05]){
       sonars();}}
   translate([sonar_holder_length, 0, 0]){
-    cube([elbow_length,
-          deck_depth,
-          sonar_holder_depth]);
+    cube([elbow_length, deck_depth, sonar_holder_depth]);
     translate([elbow_length, 0, 0]){
       linear_extrude(height = sonar_holder_depth){
-        polygon([[0, 0],
+        polygon([[                 0, 0],
                  [sonar_holder_depth, 0],
                  [sonar_holder_depth, sonar_holder_width / 2],
-                 [0, sonar_holder_width / 2 + sonar_holder_depth]]);}
+                 [                 0,
+                  sonar_holder_width / 2 + sonar_holder_depth]]);}
       translate([0, (sonar_holder_width + sonar_holder_depth) / 2, 0]){
         cube([sonar_holder_depth / 2,
               (sonar_holder_width - sonar_holder_depth) / 2 + 0.8,
               sonar_holder_depth]);}
       translate([-1.7, sonar_holder_width + 0.8, 0]){
         linear_extrude(height = sonar_holder_depth){
-          polygon([[0, 0],
+          polygon([[                           0, 0],
                    [sonar_holder_depth / 2 + 1.7, 4],
                    [sonar_holder_depth / 2 + 1.7, 0]]);}}}}}