Function_autoassembly.py

# use CQ-Editor to tune the code, moving parts to proper locations or adding constraints to make assembly
# then copy the code here



def autoassem_coldplate(CP_path, lets_path, chips_path, output=None):
    import cadquery as cq
    from cadquery import importers
    import os

    # ==========================================
    # 1.Import parts
    # ==========================================
    coldplate = importers.importStep(CP_path)
    inoutlet = importers.importStep(lets_path)
    chips = importers.importStep(chips_path)

    # ==========================================
    # 2. define location of parts
    # --- (Coldplate location) ---
    loc_base = cq.Location(cq.Vector(0, 0, 0))

    # --- (inoutlet location) ---
    loc_blue = cq.Location(cq.Vector(0, -15/2, 4.175/2), cq.Vector(1, 0, 0), 90)

    lets_location = [(0, -15/2, 4.175/2),
                    (0, 15/2+200, 4.175/2)
                                        ]

    # --- (chips location) ---
    loc_chip_1 = cq.Location(cq.Vector(7.5/2, 7.5/2, -0.125/2), cq.Vector(1,0,0), 90)

    chip_location = [
                    (7.5/2, 7.5/2, -0.125/2), 
                    (7.5/2, -7.5/2, -0.125/2),
                    (-7.5/2, 7.5/2, -0.125/2),
                    (-7.5/2, -7.5/2, -0.125/2)
                                                ]

    # ==========================================
    # 3. 组装 (Assembly)
    # ==========================================
    assem = cq.Assembly()

    # add parts into assembly
    # syntex ----- assem.add(part variable, name="assign name for this part", color=cq.Color("red"))

    # add Coldplate core
    assem.add(coldplate, name="Coldplate", loc=loc_base, color=cq.Color("red"))

    # add two header lets to the end of coldplate
    for i, pos in enumerate(lets_location):
        lets_loc = cq.Location(cq.Vector(*pos), cq.Vector(1, 0, 0), 90)
        lets_name = f"let_{i}"
        assem.add(inoutlet,  name=lets_name,  loc=lets_loc, color=cq.Color("blue"))
    # assem.add(inoutlet,  name="inlet",  loc=loc_blue, color=cq.Color("blue"))

    # add 4 chips onto the bottion of the coldplate
    for i,pos in enumerate (chip_location):
        chips_loc = cq.Location(cq.Vector(*pos), cq.Vector(1,0,0), 90)
        chips_name = f"chip_{i}"
        assem.add(chips, name=chips_name, loc=chips_loc, color=cq.Color("green"))
    # assem.add(chips,     name="chip_1",     loc=loc_chips, color=cq.Color("green"))


    if output is None:
        # obtain current user main path获取当前用户的“用户主目录” (如 C:\Users\Username)
        user_home = os.path.expanduser("~")
        # obtain desktop path 拼接出桌面路径
        desktop_path = os.path.join(user_home, "Desktop")
        # define a file name 定义一个默认文件名 
        save_path = os.path.join(desktop_path, "undefined_path_export.step")
    else:
        save_path = output 
    

    assem.save(save_path)

    return save_path











# 1.定平面 (Find Plane)：找到盒子顶面，作为侦测的基准。

# 2.找圆心 (Find XY)：在顶面上扫描所有轮廓线，取最短的那条（孔口），计算其圆心坐标 (x, y)。

# 3.找孔底 (Find Z)：扫描盒子所有朝上的平面，按高度排名。第 2 高的面即为孔底，获取其高度 z。

# 4.合体 (Assemble)：将插销的基准点直接搬运到计算出的 (x, y, z) 坐标。


def Auto_box_OneHole_OnePin(box_path, pin_path, output=None):

    import cadquery as cq
    from cadquery import importers
    import os

    # ==========================================
    # 1. Import files
    # ==========================================

    box = importers.importStep(box_path)
    pin = importers.importStep(pin_path)

    # ==========================================
    # 2. The Parametric Logic locating the hole 全自动定位逻辑 
    # ==========================================

    try:
        print("scanning geometry features...")
        
        # --- Step 1: locate center of hole 找 XY 中心  ---
        top_face = box.faces(">Z")
        wires = top_face.wires().vals()
        # Looking for the shortest perimeter 找最短的轮廓(孔口)
        hole_wire = sorted(wires, key=lambda w: w.Length())[0]
        center_xy = hole_wire.Center()
        
        
        # --- Step 2: fine the z for bottom of hole 找 Z 高度 (孔底) ---
        # fine all surface which face to the top(normal to (0,0,1)), from top to bottom 找到所有法线向上(0,0,1)的平面，按高度从高到低排序
        # [0] is the top face of box, [1]is bottom of hoel [0]是盒子顶面, [1]通常就是盲孔的底面
        all_planes = box.faces("%Plane").vals()
        upward_planes = [f for f in all_planes if f.normalAt(None).z > 0.9]
        upward_planes.sort(key=lambda f: f.Center().z, reverse=True)
        
        if len(upward_planes) > 1:
            # second height face is bottom of hole 找到了第二高的面，认为是孔底
            target_z = upward_planes[1].Center().z
            print(f"✅ detect bottom of hole: Z={target_z:.2f}")
        else:
            # 没找到(可能是通孔)，就用盒子最底面
            target_z = box.faces("<Z").val().Center().z
            print(f"⚠️ not bottom surface found, all through hole: Z={target_z:.2f}")

        # 组合最终目标坐标
        target_loc = cq.Vector(center_xy.x, center_xy.y, target_z)
        print(f"✅ locate the mating coordination: {target_loc}")
        
    except Exception as e:
        print(f"⚠️ failed to dected the hole: {e}")
        target_loc = cq.Vector(0,0,0)

    # ==========================================
    # 3. 组装 (Assembly)
    # ==========================================
    assem = cq.Assembly()

    loc_base = cq.Location(cq.Vector(0, 0, 0))

    # translate pin to the coordination just found 【关键】把插销直接放到计算好的 (x, y, z_bottom)
    loc_pin = cq.Location(target_loc)

    assem.add(box, name="box", loc=loc_base, color=cq.Color("red"))
    assem.add(pin, name="pin", loc=loc_pin, color=cq.Color("blue"))

    #  判断用户是否输入了路径
    if output is None:
        # obtain current user main path获取当前用户的“用户主目录” (如 C:\Users\Username)
        user_home = os.path.expanduser("~")
        # obtain desktop path 拼接出桌面路径
        desktop_path = os.path.join(user_home, "Desktop")
        # define a file name 定义一个默认文件名
        save_path = os.path.join(desktop_path, "undefined_path_export.step")
    else:
        save_path = output 
    

    assem.save(save_path)
    return save_path






if __name__ =="__main__":
    CP_path = r"C:\Users\lichengd\OneDrive - Oregon State University\1. PhD\Chiller\automation\Chiller_auto_Python\CAD_files\Export_Coldplate_spreadsheet.step"
    lets_path = r"C:\Users\lichengd\OneDrive - Oregon State University\1. PhD\Chiller\automation\Chiller_auto_Python\CAD_files\InOutlet_MaxWidth_step.SLDPRT.STEP"
    chips_path = r"C:\Users\lichengd\OneDrive - Oregon State University\1. PhD\Chiller\automation\Chiller_auto_Python\CAD_files\chip1_step.STEP"
    save_path = r"C:\Users\lichengd\OneDrive - Oregon State University\1. PhD\Chiller\automation\Chiller_auto_Python\CAD_files\Export_autoAssem_coldplate.step"

    result = autoassem_coldplate(CP_path, lets_path, chips_path, output=save_path)
    print(f"Assembly exported to:\n{result}")

# CP_path = r"C:\Users\lichengd\OneDrive - Oregon State University\1. PhD\Chiller\automation\Chiller_auto_Python\CAD_files\Export_Coldplate_spreadsheet.step"
# lets_path = r"C:\Users\lichengd\OneDrive - Oregon State University\1. PhD\Chiller\automation\Chiller_auto_Python\CAD_files\InOutlet_MaxWidth_step.SLDPRT.STEP"
# chips_path = r"C:\Users\lichengd\OneDrive - Oregon State University\1. PhD\Chiller\automation\Chiller_auto_Python\CAD_files\chip1_step.STEP"
# save_path = r"C:\Users\lichengd\OneDrive - Oregon State University\1. PhD\Chiller\automation\Chiller_auto_Python\CAD_files\Export_autoAssem_coldplate.step"

    box_path = r"C:\Users\lichengd\OneDrive - Oregon State University\1. PhD\Chiller\automation\Chiller_auto_Python\CAD_files\Export_Box_hole_Spreadsheet.step"
    pin_path = r"C:\Users\lichengd\OneDrive - Oregon State University\1. PhD\Chiller\automation\Chiller_auto_Python\CAD_files\Export_pin_Spreadsheet.step"
    save_path = r"C:\Users\lichengd\OneDrive - Oregon State University\1. PhD\Chiller\automation\Chiller_auto_Python\CAD_files\Export_autoAssem_BoxPin.step"
    result = Auto_box_OneHole_OnePin(box_path,pin_path, output=save_path)
    print(f"Assembly exported to:\n{result}")