OpenScad model / animation for an elastic spring shield

binderprototype.scad

module ring(inner_radius, thickness, height) 
{ 
   outer_radius = inner_radius + thickness;
   padding = 0.1;
 
   difference() 
	{
      cylinder(r=outer_radius,h=height,center=true);
      cylinder(r=inner_radius,h=height+padding,center=true);
		translate([0,outer_radius,0])
			cube([outer_radius*2,outer_radius*2,height+padding], center = true);
		translate([outer_radius * 0.9,0,0])
			cube([height+padding,outer_radius,height+padding], center = true);
   }
}

module binder_ring(position, size)
{
	thickness = 0.2;
	height = 0.3;
	translate(position)
	{
		translate([-0.5 + $t * 0.5, -1 + $t, 0])
			rotate([0,0,75 - $t * 80])
				ring(size, thickness, height, $fn = 20);	
		mirror([0,1,0])
			translate([-0.5 + $t * 0.5, -1 + $t, 0])
				rotate([0,0,75 - $t * 80])
					ring(size, thickness, height, $fn = 20);
		}
}

module arrow(scale)
{
	polygon([[0,-1*scale],[0,scale],[0.7*scale,0]],[[0,1,2]]);
	translate([-0.5*scale,0,0])
		cube([scale,scale,1],center = true);
}

render()
{
	// cylinder body
	difference()
	{
		resize([2.8 - 0.5 * $t ,2.24 + 0.5 * $t,10]) 
			cylinder($fn = 20);
	
		resize([2.3 - 0.411 * $t, 1.84 + 0.411 * $t,11])
			cylinder($fn = 20);
	}


	// leaves
	translate([-0.5 + $t,0,0])
	{
		translate([-0.05,0.005,0])
		rotate([0,0,-30 + 60 * $t])
			cube([0.25,1.20,10]);
		translate([0.2,-0.005,0])
			rotate([0,0,180])
			{
				rotate([0,0,-(-30 + 60 * $t)])
					cube([0.25,1.19,10]);
			}
	}
	
	// rings
	binder_ring([-1.3,0,0.7], 1.5);
	binder_ring([-1.3,0,5], 1.5);
	binder_ring([-1.3,0,9.3], 1.5);

}

translate([-3 + 0.7 * $t,0,2])
	arrow(1.5);
translate([-3 + 0.7 * $t,0,5])
	arrow(1.5);
translate([-3 + 0.7 * $t,0,8])
	arrow(1.5);