Build a drone: landing gear

Four legs stand under the arms. Each part of a leg is made once, 52 millimetres out along the x axis, and the Around module repeats it four times; the count comes from the legs number in the Sizes group, which also made the openings the legs pass through.

1. A leg is a carbon tube bent twice on its way down, with a flange and a boss that pass through the leg opening. A code component sweeps a circle along the bent path, and Around repeats the leg four times, under the arms.

   • Add typescript editor as leg: hidden, with the code below.

   • Add Module Instance as legs around: module Around.

   • Wire leg › result into legs around › shape.

   • Wire legs › result into legs around › count.

   • Wire legs around › copies into carbon › entity.

   • Press Add a comment, double-click the comment and write:

     Landing gear

     One leg is made along the x axis, 52 mm out: a bent carbon tube, a damper with its spring, and a rubber foot. Around repeats each part four times, under the arms.

   • Select the comment, leg and legs around, press Group selected components and title the group Landing gear.

   const start = async (inputs: any, index: number) => {
       const path = await bitbybit.occt.shapes.wire.createPolylineWire({ points: [[52, 0, 0], [58, -18, 0], [78, -34, 0], [78, -48, 0]] });
       const bent = await bitbybit.occt.fillets.fillet3DWire({ shape: path, radiusList: [12, 6], indexes: [0, 1], direction: [0, 0, 1] });
       const tube = await bitbybit.occt.operations.pipeWireCylindrical({ shape: bent, radius: 4, makeSolid: true, trihedronEnum: "isConstantNormal", forceApproxC1: false });
       const flange = await bitbybit.occt.shapes.solid.createBox({ width: 20, length: 12, height: 3, center: [52, -1.5, 0] });
       const boss = await bitbybit.occt.shapes.solid.createCylinder({ radius: 5.5, height: 6.4, center: [52, -3, 0], direction: [0, 1, 0] });
       return bitbybit.occt.booleans.union({ shapes: [tube, flange, boss], keepEdges: false });
   }

   

2. At the end of each leg a damper. Its aluminium body is a profile of twelve points revolved around its rod, which a code component says most plainly. The steel spring around it is two nodes: a helix wire, and a pipe swept along it. Each repeats four times like the leg.

   • Add typescript editor as damper: hidden, in the Landing gear group, with the code below.
   • Add create helix wire as spring helix: radius 4.2, pitch 2.8, height 12.5, center [78, -75.8, 0], direction [0, 1, 0], clockwise off, tolerance 0.0001, hidden, in the Landing gear group.
   • Add pipe wire cylindrical as spring: radius 0.9, make solid on, trihedron enum isCorrectedFrenet, force approx c1 off, hidden, in the Landing gear group.
   • Wire spring helix › result into spring › shape.
   • Add Module Instance as dampers around: module Around, in the Landing gear group.
   • Wire damper › result into dampers around › shape.
   • Wire legs › result into dampers around › count.
   • Add Module Instance as springs around: module Around, in the Landing gear group.
   • Wire spring › result into springs around › shape.
   • Wire legs › result into springs around › count.
   • Wire dampers around › copies into aluminium › entity.
   • Wire springs around › copies into steel › entity.

   const start = async (inputs: any, index: number) => {
       const profile = [[0, 0, 0], [6.5, 0, 0], [6.5, -4, 0], [5.5, -4.5, 0], [5.5, -14, 0], [6.2, -14, 0], [6.2, -16.5, 0], [4, -16.5, 0], [4, -18, 0], [2.2, -18, 0], [2.2, -30, 0], [0, -30, 0]];
       const outline = await bitbybit.occt.shapes.wire.createPolygonWire({ points: profile });
       const face = await bitbybit.occt.shapes.face.createFaceFromWire({ shape: outline, planar: true });
       const body = await bitbybit.occt.operations.revolve({ shape: face, angle: 360, direction: [0, 1, 0], copy: false });
       return bitbybit.occt.transforms.translate({ shape: body, translation: [78, -46, 0] });
   }

   

3. A rubber foot is lofted through five circles, and two of the M3 bolts fix each leg's flange to the plate.

   • Add typescript editor as foot: hidden, in the Landing gear group, with the code below.
   • Add Module Instance as feet around: module Around, in the Landing gear group.
   • Wire foot › result into feet around › shape.
   • Wire legs › result into feet around › count.
   • Wire feet around › copies into rubber › entity.
   • Add translate as inner leg bolt: translation [44.5, -3, 0], hidden, in the Landing gear group.
   • Add translate as outer leg bolt: translation [59.5, -3, 0], hidden, in the Landing gear group.
   • Wire M3 bolt › result into inner leg bolt › shape.
   • Wire M3 bolt › result into outer leg bolt › shape.
   • Add create list as leg bolts in the Landing gear group.
   • Wire inner leg bolt › result into leg bolts › listElements.
   • Wire outer leg bolt › result into leg bolts › listElements.
   • Add make compound as leg bolt pair: hidden, in the Landing gear group.
   • Wire leg bolts › list into leg bolt pair › shapes.
   • Add Module Instance as leg bolts around: module Around, in the Landing gear group.
   • Wire leg bolt pair › result into leg bolts around › shape.
   • Wire legs › result into leg bolts around › count.
   • Wire leg bolts around › copies into steel › entity.

   const start = async (inputs: any, index: number) => {
       const rings = [];
       for (const [y, radius] of [[0, 3.2], [-2, 7], [-5, 9.5], [-8, 9], [-10, 7]]) {
           rings.push(await bitbybit.occt.shapes.wire.createCircleWire({ radius, center: [78, -76 + y, 0], direction: [0, 1, 0] }));
       }
       return bitbybit.occt.operations.loft({ shapes: rings, makeSolid: true });
   }

   

Next: payload and sliders.