# -*- coding: utf-8 -*- """ BF-B 超轻型载人飞行器机架 —— 实拍复刻参数化建模（弯管版） 运行于 FreeCAD 1.0.2 headless (FreeCADCmd.exe) 参照董总提供的两张实拍（泪滴形防滚拱机架）： · 主拱：鹅蛋形弯管，前腿落地接床身，越顶后顺滑下接尾部方盒顶 · 机头：两侧管向前收锥汇拢 + 鼻环，前方 V 形斜撑 · 底部：平梯式床身（双纵梁 + 密横梁） · 尾部：方盒（四角立柱 + 顶框 + 中轨 + 斜撑） · 侧面：床身与拱/顶管之间 X 形三角撑 输入：外廓 750 x 2200 x 1100，主骨架 φ45，次骨架 φ30，6061 输出：FCStd / STEP / STL / preview-mini.svg / model.json """ import FreeCAD as App import Part from FreeCAD import Vector import os, math, json, sys def log(*a): print(*a) sys.stdout.flush() OUT = "C:/Users/DEYI/WorkBuddy/2026-09-20-12-27-14/bf-b2" if not os.path.isdir(OUT): os.makedirs(OUT) # ============================================================ # ① 参数 # ============================================================ D_MAIN, D_SUB = 45.0, 30.0 T_MAIN, T_SUB = 2.0, 2.0 RHO_AL = 2.70e-3 # g/mm3 HW = 375.0 # 半宽（外廓） XC_MAIN = 352.0 # 拱/顶管中心线 x（375-22.5） XC_BED = 340.0 # 床身纵梁中心线 x BED_Z = 112.0 # 床身纵梁中心线高 TAIL_Z0, TAIL_Z1 = 112.0, 642.0 # 尾部方盒底/顶（中心线） TAIL_Y0, TAIL_Y1 = 680.0, 1080.0 # 主拱中心线（侧视 y,z；x=±XC_MAIN）—— 鹅蛋形：前腿微前凸，顶点靠前 1/3，后段下滑接尾盒顶 ARCH_PTS = [ (-980.0, 132.0), (-1015.0, 330.0), (-1018.0, 520.0), (-975.0, 730.0), (-890.0, 905.0), (-760.0, 1030.0), (-570.0, 1078.0), # 顶点（全高 1100 - 管半径） (-330.0, 1070.0), (-80.0, 1010.0), (170.0, 920.0), (400.0, 800.0), (545.0, 700.0), (640.0, 642.0), # 接尾部方盒顶前角 ] # ============================================================ # ② 造型工具 # ============================================================ def spline_of(pts): sp = Part.BSplineCurve() sp.interpolate(pts) return sp def bent_tube(pts, r, tag=""): """样条扫掠弯管；样条长度超差或扫掠失败则退化为分段圆柱+节点球。返回 (shape, 采样点列, 长度)""" poly_len = sum((Vector(*pts[i + 1]) - Vector(*pts[i])).Length for i in range(len(pts) - 1)) sp = spline_of([Vector(*p) for p in pts]) path = Part.Wire([sp.toShape()]) t0 = sp.tangent(sp.FirstParameter)[0] prof = Part.Wire([Part.makeCircle(r, Vector(*pts[0]), t0)]) try: solid = path.makePipeShell([prof], True, False) if solid.ShapeType != "Solid": solid = Part.Solid(solid) if not solid.isValid() or solid.Volume <= 0: raise RuntimeError("invalid sweep") if path.Length > poly_len * 1.08: raise RuntimeError("spline overshoot: %.0f >> %.0f" % (path.Length, poly_len)) us = [sp.FirstParameter + (sp.LastParameter - sp.FirstParameter) * i / 40.0 for i in range(41)] samp = [sp.value(u) for u in us] log(" [弯管] %s 扫掠 OK 体积 %.1f cm3 长度 %.0f mm" % (tag, solid.Volume / 1000.0, path.Length)) return solid, samp, path.Length except Exception as e: log(" [弯管] %s 改用分段直管(%s)" % (tag, e)) # 线性细分（不依赖样条，杜绝过冲） samp = [] for i in range(len(pts) - 1): a, b = Vector(*pts[i]), Vector(*pts[i + 1]) n = max(2, int((b - a).Length / 45.0)) for k in range(n): samp.append(a + (b - a) * (k / float(n))) samp.append(Vector(*pts[-1])) segs = [] for i in range(len(samp) - 1): a, b = samp[i], samp[i + 1] segs.append(Part.makeCylinder(r, (b - a).Length, a, b - a)) for p in samp[1:-1]: segs.append(Part.makeSphere(r, p)) L = sum((samp[i + 1] - samp[i]).Length for i in range(len(samp) - 1)) return Part.makeCompound(segs), samp, L def rod(p1, p2, r): v = p2 - p1 return Part.makeCylinder(r, v.Length, p1, v) shapes = [] # 实体汇总 draw = [] # (pts3d, dia, kind) 供 SVG rod_len = {"main": 0.0, "sub": 0.0} # mm def add_straight(p1, p2, d, kind): r = d / 2.0 shapes.append(rod(Vector(*p1), Vector(*p2), r)) draw.append(([Vector(*p1), Vector(*p2)], d, kind)) rod_len["main" if kind == "main" else "sub"] += (Vector(*p2) - Vector(*p1)).Length def add_curve(pts3d, d, kind, tag): r = d / 2.0 vs = [Vector(*p) for p in pts3d] shape, samp, L = bent_tube(vs, r, tag) shapes.append(shape) draw.append((samp, d, kind)) rod_len["main" if kind == "main" else "sub"] += L # ============================================================ # ③ 机架杆件 # ============================================================ def arch_z(y): """拱中心线在纵向 y 处的高度（按 ARCH_PTS 线性插值）""" pts = ARCH_PTS for i in range(len(pts) - 1): (y0, z0), (y1, z1) = pts[i], pts[i + 1] if min(y0, y1) <= y <= max(y0, y1): t = (y - y0) / (y1 - y0) return z0 + t * (z1 - z0) return pts[-1][1] NOSE_Y = -1090.0 NOSE_TIP_X, NOSE_TIP_Z = 85.0, 320.0 # 机头尖端（半宽, 高） log("== 主拱（弯管，前腿落在底梁上）==") for sgn, tag in ((-1, "左拱"), (1, "右拱")): pts = [(sgn * XC_MAIN, y, z) for (y, z) in ARCH_PTS] add_curve(pts, D_MAIN, "main", tag) log("== 顶部纵梁（拱尾→尾盒顶后角）==") for sgn in (-1, 1): add_straight((sgn * XC_MAIN, 640.0, 642.0), (sgn * XC_MAIN, TAIL_Y1, TAIL_Z1 - 2.0), D_MAIN, "main") log("== 底梁（下弦：尾端长直段[圆柱] + 前端上翘收锥弯管至机头尖）==") for sgn, tag in ((-1, "左底梁"), (1, "右底梁")): # 长直段不用样条（避免插值过冲），直接圆柱 add_straight((sgn * XC_BED, 1090.0, BED_Z), (sgn * XC_BED, -880.0, BED_Z), D_MAIN, "main") # 机头弯头：短样条，路径全部短段 curve = [(sgn * XC_BED, -880.0, BED_Z), (sgn * XC_BED, -950.0, 128.0), (sgn * 280.0, -1045.0, 200.0), (sgn * 170.0, -1082.0, 275.0), (sgn * NOSE_TIP_X, NOSE_Y, NOSE_TIP_Z)] add_curve(curve, D_MAIN, "main", tag) log("== 鼻环（连接左右机头尖）==") add_curve([(-NOSE_TIP_X, NOSE_Y, NOSE_TIP_Z), (0.0, NOSE_Y, 440.0), (NOSE_TIP_X, NOSE_Y, NOSE_TIP_Z)], D_SUB, "sub", "鼻环") log("== 床身横梁（梯）==") bed_cross_ys = [-800, -670, -540, -410, -280, -150, -20, 110, 240, 370, 500, 630, 760, 890, 1020] for y in bed_cross_ys: add_straight((-XC_BED, y, BED_Z), (XC_BED, y, BED_Z), D_SUB, "sub") log(" 床身横梁 %d 根" % len(bed_cross_ys)) log("== 尾部方盒 ==") for sx in (-1, 1): for y in (TAIL_Y0, TAIL_Y1): add_straight((sx * XC_MAIN, y, TAIL_Z0), (sx * XC_MAIN, y, TAIL_Z1), D_MAIN, "main") # 四角立柱 add_straight((sx * XC_MAIN, TAIL_Y0, 380.0), (sx * XC_MAIN, TAIL_Y1, 380.0), D_SUB, "sub") # 侧中轨 add_straight((sx * XC_MAIN, TAIL_Y1, TAIL_Z0), (sx * XC_MAIN, TAIL_Y0, 380.0), D_SUB, "sub") # 侧斜撑 add_straight((-XC_MAIN, TAIL_Y0, TAIL_Z1), (XC_MAIN, TAIL_Y0, TAIL_Z1), D_MAIN, "main") # 顶前横 add_straight((-XC_MAIN, TAIL_Y1, TAIL_Z1), (XC_MAIN, TAIL_Y1, TAIL_Z1), D_MAIN, "main") # 顶后横 add_straight((-XC_BED, 1090.0, BED_Z), (XC_BED, 1090.0, BED_Z), D_MAIN, "main") # 底后横 add_straight((0.0, TAIL_Y1, TAIL_Z0), (0.0, TAIL_Y1, TAIL_Z1), D_SUB, "sub") # 尾面中立柱 log("== 机头区撑杆（端点全部落在拱/底梁中心线上）==") for sgn in (-1, 1): # 拱前腿三角撑：底梁 → 拱（y=-975 处 z=730） add_straight((sgn * XC_BED, -780.0, BED_Z), (sgn * XC_MAIN, -975.0, arch_z(-975.0)), D_SUB, "sub") # 机头尖 → 拱前腿（长 V 撑，落点 y=-940） add_straight((sgn * NOSE_TIP_X, NOSE_Y, NOSE_TIP_Z + 25.0), (sgn * XC_MAIN, -940.0, arch_z(-940.0)), D_SUB, "sub") # 底梁 → 机头尖（短撑） add_straight((sgn * XC_BED, -850.0, BED_Z), (sgn * (NOSE_TIP_X + 20.0), -1085.0, NOSE_TIP_Z - 30.0), D_SUB, "sub") log("== 侧面 X 撑（拱后段—底梁）与立柱 ==") for sgn in (-1, 1): for (ya, yb) in ((-300.0, 100.0), (350.0, 640.0)): add_straight((sgn * XC_BED, ya, BED_Z), (sgn * XC_MAIN, yb, arch_z(yb)), D_SUB, "sub") add_straight((sgn * XC_BED, yb, BED_Z), (sgn * XC_MAIN, ya, arch_z(ya)), D_SUB, "sub") add_straight((sgn * XC_MAIN, 300.0, BED_Z), (sgn * XC_MAIN, 300.0, arch_z(300.0)), D_SUB, "sub") # 中立柱 log("== 座舱内横撑（端点在拱中心线上）==") add_straight((-XC_MAIN, -1000.0, arch_z(-1000.0)), (XC_MAIN, -1000.0, arch_z(-1000.0)), D_SUB, "sub") add_straight((-XC_MAIN, -950.0, arch_z(-950.0)), (XC_MAIN, -950.0, arch_z(-950.0)), D_SUB, "sub") frame_shape = Part.makeCompound(shapes) bb = frame_shape.BoundBox log("[机架] 实体数 = %d BBox = %.0f x %.0f x %.0f mm" % (len(shapes), bb.XLength, bb.YLength, bb.ZLength)) mass = (rod_len["main"] * math.pi * ((D_MAIN / 2) ** 2 - (D_MAIN / 2 - T_MAIN) ** 2) + rod_len["sub"] * math.pi * ((D_SUB / 2) ** 2 - (D_SUB / 2 - T_SUB) ** 2)) * RHO_AL log("[机架] φ45 总长 %.1f m φ30 总长 %.1f m 净重 ≈ %.2f kg" % (rod_len["main"] / 1000, rod_len["sub"] / 1000, mass / 1000)) # ============================================================ # ④ 导出 # ============================================================ doc = App.newDocument("BF_B_frame") o1 = doc.addObject("Part::Feature", "BF_B_Frame_750x2200x1100") o1.Shape = frame_shape doc.recompute() doc.saveAs(os.path.join(OUT, "BF-B-frame.FCStd")) try: Part.export([o1], os.path.join(OUT, "BF-B-frame.step")) log("[导出] STEP ok") except Exception as e: log("[导出] STEP 失败", e) try: import Mesh, MeshPart m = MeshPart.meshFromShape(Shape=o1.Shape, LinearDeflection=1.0, AngularDeflection=0.6, Relative=False) m.write(os.path.join(OUT, "bframe.stl")) log("[导出] STL ok 面数 %d" % m.CountFacets) except Exception as e: log("[导出] STL 失败", e) # ============================================================ # ⑤ 等轴测线框 SVG（viewer 降级图） # ============================================================ C_MAIN, C_SUB, C_INK = "#2b3a45", "#9aa9b4", "#42545f" W_SVG, H_SVG = 680, 430 def iso(p): c30, s30 = math.cos(math.radians(30)), math.sin(math.radians(30)) return (p.x - p.y) * c30, (p.x + p.y) * s30 - p.z allp = [] for pts, d, k in draw: allp.extend(pts) proj = [iso(p) for p in allp] xs = [q[0] for q in proj]; ys = [q[1] for q in proj] x0, x1, y0, y1 = min(xs), max(xs), min(ys), max(ys) sc = min((W_SVG - 50) / (x1 - x0), (H_SVG - 60) / (y1 - y0)) * 0.95 ox = (W_SVG - (x1 - x0) * sc) / 2 - x0 * sc oy = (H_SVG - 40 - (y1 - y0) * sc) / 2 + 30 - y0 * sc s = ['' % (W_SVG, H_SVG)] s.append('' % (W_SVG, H_SVG)) s.append('BF-B 机架 · 等轴测 — 深色 φ45 主骨架 / 浅灰 φ30 撑杆' % C_INK) segs = [] for pts, d, k in draw: for i in range(len(pts) - 1): a = iso(pts[i]); b = iso(pts[i + 1]) segs.append((a[0] * sc + ox, a[1] * sc + oy, b[0] * sc + ox, b[1] * sc + oy, d, k)) segs.sort(key=lambda t: t[0] + t[1]) for ax, ay, bx, by, d, k in segs: s.append('' % (ax, ay, bx, by, C_MAIN if k == "main" else C_SUB, max(0.8, d * sc * 0.8))) s.append('') open(os.path.join(OUT, "preview-mini.svg"), "w", encoding="utf-8").write("".join(s)) log("[SVG] preview-mini.svg 已生成") # ============================================================ # ⑥ model.json # ============================================================ json.dump({ "meta": {"name": "BF-B", "type": "实拍复刻弯管桁架机架", "total": [750, 2200, 1100], "d_main": D_MAIN, "d_sub": D_SUB, "len_main_m": round(rod_len["main"] / 1000, 1), "len_sub_m": round(rod_len["sub"] / 1000, 1), "frame_mass_kg": round(mass / 1000, 2), "solids": len(shapes)}, "arch_profile": ARCH_PTS, }, open(os.path.join(OUT, "model.json"), "w", encoding="utf-8"), ensure_ascii=False) log("=== DONE ===")