X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=lipo-flat-mount.scad;fp=lipo-flat-mount.scad;h=98d4baac350a64335dc8ba8c1cd4c3cf04f53a6f;hb=09e035d26f752d55966f8dc4ebf5f219767f20ac;hp=0000000000000000000000000000000000000000;hpb=9191f0a4821e3e8cf6567b13a5de0d42b018cc2b;p=reprap-play.git

diff --git a/lipo-flat-mount.scad b/lipo-flat-mount.scad
new file mode 100644
index 0000000..98d4baa
--- /dev/null
+++ b/lipo-flat-mount.scad
@@ -0,0 +1,168 @@
+// -*- C -*-
+
+include <nutbox.scad>
+
+// pimoroni 3000mAh
+battery = [ 51.5,
+	    81.3,
+	    8.0 ];
+
+battery_wall = 2.0;
+battery_wall_unsupp = 4.0;
+battery_wall_top_gap = 0.75;
+
+battery_keeper_m_th = 4;
+battery_keeper_m_w = 4;
+battery_keeper_x_gap = 0.75; // each side
+battery_keeper_y_gap_overhang = 0.75;
+battery_keeper_y_gap_nutbox = 1.0;
+battery_keeper_z_gap_nutbox = 0.50;
+battery_keeper_z_gap_overhang = 0.75;
+
+battery_keeper_x_th_min = 1.5 * 1.5;
+battery_keeper_x_th_max = 2.5 * 1.5;
+battery_keeper_x_w  = 5;
+battery_keeper_x_n  = 5;
+
+battery_keeper_screw_x_off = -2.5;
+
+battery_wire_y = 4;
+
+battery_nutbox = nutbox_data_M3;
+
+// calculated
+
+battery_nutbox_z = max( battery[2] + battery_wall_top_gap,
+			NutBox_h_base(battery_nutbox) );
+battery_keeper_overhang_z = battery[2] + battery_keeper_m_th
+  + battery_keeper_z_gap_overhang;
+battery_keeper_overhang_wall = battery_keeper_m_w;
+battery_keeper_overhang_th = battery_keeper_m_th;
+
+module BatteryPlan(){
+  rectfromto([ -battery[0]/2, 0          ],
+	     [ +battery[0]/2, battery[1] ]);
+}
+
+module BatteryBase(){ ////toplevel
+  // wall
+  linextr(-0.1, battery[2] - battery_wall_top_gap, convexity=7) {
+    difference(){
+      union(){
+	offset(r=battery_wall) BatteryPlan();
+	rectfromto([ 0,0 ],
+		   [ -(battery[0]/2 + battery_wall_unsupp), battery[1]/3 ]);
+      }
+      BatteryPlan();
+      rectfromto([ fix_sz/2 - 0.5
+		   + battery_keeper_screw_x_off, -30 ],
+		 [ -battery[0], battery_wire_y ]);
+    }
+  }
+
+  // nutbox
+  translate([battery_keeper_screw_x_off, -fix_sz/2, battery_nutbox_z])
+    NutBox(battery_nutbox, battery_nutbox_z + 0.1);
+
+  // overhang for legs at rear
+  for (m=[0,1]) {
+    mirror([m,0,0]) {
+      translate([ battery[0]/2, battery[1], 0]) {
+	difference(){
+	  linextr(-0.1,
+		  battery_keeper_overhang_z
+		  + battery_keeper_overhang_th,
+		  convexity=1)
+	    rectfromto([ -battery_keeper_m_w*2, -battery_keeper_m_w ],
+		       [ battery_keeper_overhang_wall, battery_wall ]);
+	  linextr(-1, battery_keeper_overhang_z,
+		  convexity=1)
+	    rectfromto([-20, -20], [0,0]);	    
+	}
+      }
+    }
+  }
+}
+
+module BatteryKeeper(){ ////toplevel
+  // A-frame
+  translate([0,0, battery[2]]) {
+    linextr(0, battery_keeper_m_th) {
+      intersection(){
+	// main legs
+	translate([0,  +battery[1], 0])
+	  multmatrix([[ 1, -battery_keeper_screw_x_off/battery[1], 0, 0, ],
+		      [ 0,1,0, 0, ],
+		      [ 0,0,1, 0, ]])
+	  translate([0, -battery[1], 0])
+	for (sx=[-1,+1]) {
+	  multmatrix([[ 1,0,0, 0, ],
+		      [ 0,1,0, 0, ],
+		      [ 0,0,1, 0, ]] +
+		     sx *
+		     ( battery[0]/2 - 0.5 * battery_keeper_m_w
+		       - battery_keeper_x_gap ) /
+		     ( battery[1] - 0.5 * battery_keeper_m_w )
+		     *
+		     [[ 0,1,0, 0, ],
+		      [ 0,0,0, 0, ],
+		      [ 0,0,0, 0, ]])
+	    rectfromto([ -battery_keeper_m_w/2,
+			 battery_keeper_y_gap_nutbox ],
+		       [ +battery_keeper_m_w/2,
+			 battery[1] - battery_keeper_y_gap_overhang ]);
+	}
+
+	// shape to round off the leg end corners
+	hull(){
+	  for (sx=[-1,+1]) {
+	    translate([ sx * ( battery[0]/2 - battery_keeper_m_w/2
+			       -battery_keeper_x_gap) ,
+			battery[1] - battery_keeper_m_w/2
+			-battery_keeper_y_gap_overhang ])
+	      circle(r = battery_keeper_m_w/2);
+	  }
+	  square(center=true, [ battery[0], 1 ]);
+	}
+      }
+    }
+
+    // x struts
+    for (i=[0 : battery_keeper_x_n-1]) {
+      linextr(0,
+	      battery_keeper_x_th_min +
+	      (battery_keeper_x_th_max - battery_keeper_x_th_min)
+	      * pow( i/(battery_keeper_x_n-1)*2 - 1 , 2)
+	      ) {
+	difference(){
+	  translate([0, battery[1] * ((i + 0.5) / battery_keeper_x_n)])
+	    square(center=true, [ battery[0], battery_keeper_x_w ]);
+	  rectfromto([ -battery[1], -20 ],
+		     [ +pi_sz[1] - pi_usb_from_other_side,
+		       pi_usb_over_battery_proportion * battery[1] ]);
+	}
+      }
+    }
+  }
+
+  // tab for screw and nutbox
+  translate([battery_keeper_screw_x_off,
+	     0,
+	     battery_nutbox_z + battery_keeper_z_gap_nutbox])
+    linextr(0, battery_keeper_m_th, convexity=4) {
+    difference(){
+      rectfromto([ -fix_sz/2, -fix_sz ],
+		 [ +fix_sz/2,
+		   0.5 * battery[1] / battery_keeper_x_n +
+		   0.5 * battery_keeper_m_w ]);
+      translate([ 0, -fix_sz/2 ])
+	circle(r = battery_nutbox[0]/2);
+    }
+  }
+}
+
+module BatteryDemo(){ ////toplevel
+  color("grey") BatteryBase();
+  BatteryKeeper();
+}
+