pdf-page/gpt-5.5 / tier-4-gp2y0a21yk

```openscad
$fn = 96;

// GP2Y0A21YK0F outline model, units: mm
// Coordinate system: main lens-case center at origin, +Z up, +Y front

body_x = 29.5;
body_y = 13.5;
body_z = 13.0;

overall_x = 37.0;

mount_boss_d = 7.5;      // R3.75
mount_hole_d = 3.2;
mount_x = overall_x/2 - mount_boss_d/2;

lens_sep = 20.0;         // * reference lens-center spacing
emitter_x = -body_x/2 + 4.5;   // * reference from left side
detector_x = emitter_x + lens_sep;

plate_th = 2.0;
plate_z = -body_z/2 + plate_th/2;

bar_len = 7.5;
bar_y_front = -body_y/2;
bar_y_center = bar_y_front - bar_len/2;

neck_w = 14.75;
neck_len = 7.25;
neck_y_center = bar_y_front - bar_len - neck_len/2;
rear_y = bar_y_front - bar_len - neck_len;   // -21.5

cable_notch_w = 10.1;
cable_notch_d = 3.3;

module cube_c(size, pos=[0,0,0]) {
    translate(pos) cube(size, center=true);
}

module rounded_rect_2d(w, h, r) {
    hull() {
        translate([ w/2-r,  h/2-r]) circle(r=r);
        translate([-w/2+r,  h/2-r]) circle(r=r);
        translate([ w/2-r, -h/2+r]) circle(r=r);
        translate([-w/2+r, -h/2+r]) circle(r=r);
    }
}

module mounting_bar_2d() {
    difference() {
        union() {
            hull() {
                translate([-mount_x, bar_y_center]) circle(d=mount_boss_d);
                translate([ mount_x, bar_y_center]) circle(d=mount_boss_d);
            }
            translate([0, neck_y_center])
                rounded_rect_2d(neck_w, neck_len, 0.6);
        }

        translate([-mount_x, bar_y_center]) circle(d=mount_hole_d);
        translate([ mount_x, bar_y_center]) circle(d=mount_hole_d);

        translate([0, rear_y + cable_notch_d/2])
            square([cable_notch_w, cable_notch_d + 0.02], center=true);
    }
}

module mounting_bar() {
    color([0.03,0.03,0.03])
    translate([0,0,plate_z])
        linear_extrude(height=plate_th, center=true)
            mounting_bar_2d();
}

module main_case() {
    color([0.035,0.035,0.035])
        cube_c([body_x, body_y, body_z]);

    color([0.01,0.01,0.01])
        cube_c([body_x, 6.3, 1.2], [0, 0, body_z/2 + 0.6]);

    color([0.012,0.012,0.012])
        cube_c([body_x - 2.0, body_y - 2.0, 0.35], [0, 0, body_z/2 + 0.18]);
}

module plano_lens(d=6.3, h=1.6) {
    color([0.75,0.90,1.0,0.55])
    union() {
        cylinder(d=d, h=h*0.65, center=false);
        translate([0,0,h*0.65])
            scale([d/2, d/2, h*0.35])
                sphere(r=1);
    }
}

module emitter_lens() {
    z0 = body_z/2 + 0.22;

    color([0.0,0.0,0.0])
        cube_c([8.4, 8.4, 0.45], [emitter_x, 0, z0]);

    color([0.12,0.12,0.12])
        translate([emitter_x, 0, body_z/2 + 0.45])
            cylinder(d=7.2, h=0.45, center=false);

    translate([emitter_x, 0, body_z/2 + 0.82])
        plano_lens(5.8, 1.65);
}

module detector_lens() {
    z0 = body_z/2 + 0.22;

    color([0.0,0.0,0.0])
        cube_c([11.0, 8.4, 0.45], [detector_x, 0, z0]);

    color([0.16,0.16,0.16])
        cube_c([8.0, 5.8, 0.55], [detector_x, 0, body_z/2 + 0.52]);

    translate([detector_x, 0, body_z/2 + 0.82])
        plano_lens(6.3, 1.65);
}

module mounting_hole_visuals() {
    color([0.0,0.0,0.0]) {
        translate([-mount_x, bar_y_center, plate_z])
            cylinder(d=mount_hole_d, h=plate_th + 0.06, center=true);
        translate([ mount_x, bar_y_center, plate_z])
            cylinder(d=mount_hole_d, h=plate_th + 0.06, center=true);
    }
}

module cable() {
    cable_len = 35;
    cable_d = 3.3;

    color([0.02,0.02,0.02])
        translate([0, rear_y - cable_len/2, plate_z])
            rotate([90,0,0])
                cylinder(d=cable_d, h=cable_len, center=true);

    wire_len = 18;
    for (i=[-1,0,1]) {
        col = i == -1 ? [1,1,1] : i == 0 ? [0.05,0.05,0.05] : [0.85,0.05,0.05];
        color(col)
            translate([i*1.25, rear_y - wire_len/2 - 2.0, plate_z + 0.05])
                rotate([90,0,0])
                    cylinder(d=0.75, h=wire_len, center=true);
    }
}

module gp2y0a21yk0f() {
    mounting_bar();
    main_case();
    emitter_lens();
    detector_lens();
    mounting_hole_visuals();
    cable();
}

gp2y0a21yk0f();
```