Parts that all get called joint links are judged by completely different standards in the lower and upper limbs.

• Impact load — landing, emergency stops and single-leg support all produce transient impact; the part must be stiff without added weight, or the ankle shows elastic lag and gait chatter.
• Thin wall stiffness — 3 mm walls in 7075 deflect easily under clamping force, so we use vacuum chucking, light cuts and symmetrical material removal rather than clamp-then-mill.
• Dual bearing coaxiality — if the two H7 bearing bores are not coaxial, the outer rings are forced to tilt and bearing life is halved. We bore both in one clamping to 0.01 mm coaxiality.
• Sensor Cable Routing — the six-axis force sensor and encoder harness pass through the sole plate; channels are R2 or larger and polished so long-term gait vibration does not wear through the insulation.
• Weight Is Runtime — every 100 g removed from the lower limbs measurably improves runtime and joint motor temperature rise.

Every humanoid robot ankle is a different structure, so off-the-shelf parts mean nothing here.

• Bearing and pin matching — bore and shoulder customized to your crossed roller, deep groove or self-lubricating bushing selection.
• Stiffness Customization — rib direction and wall thickness tuned to machine mass and gait frequency, optimal between 2.5 and 5 mm.
• Material Options — 7075 for weight saving, 6061 for cost, titanium for corrosion resistance; we provide a weight and cost comparison of all three.
• Sensor Integration — six-axis force sensor mounting face and cable channel reserved, with clearance pockets cut to the sensor model.
• Small batch validation — start from one piece, 3-5 iterations with your test bench, drawing revisions fully traceable.

The drawings of a complete humanoid robot are often the core competitiveness of the next machine generation. We apply both physical and data isolation on a per-project basis.

• NDA First — mutual NDA and non-circumvention agreement signed before drawings are received.
• Isolated Secure Area — dedicated machines and staff, no photography and no phones inside the area.
• Not displayed — drawings, part photos and customer logos never enter sample cabinets, catalogs, the website or social media.
• Data Isolation — programs and models sit on an access-controlled server, destroyed at project end with a written record.
• Code-named — traveler cards and packaging labels use internal codes instead of customer part numbers.
• Version Control — every drawing revision is archived separately and superseded programs destroyed as agreed.

Dongguan Changxinda Precision Technology Co., Ltd.Founded in 2008, with a team of 90-102 staff, serving 200+ Customers, export share 50-60%, annual sales of USD 10-20 million, ISO 9001:2015 certified.

Our approach to robot structural parts is to keep tolerances inside the factory: rough machining, stress relief, finishing, surface treatment and CMM inspection all happen on one site, so thin-wall parts do not distort in transit and handling, and no fitting is needed on the customer's line.

• Reserved Capacity — machine time is locked weekly for volume programs, so rush orders never displace batch schedules.
• Two shifts, six days a week — production runs 07:30-22:00, with weekend shifts added in peak season.
• Buffer Stock — semi-finished stock is held for repeat specifications, cutting repeat order lead time by about 30%.
• Visible Progress — weekly progress sheet plus shop floor photos, tracking number issued at shipment.
• Shipping — samples by express in 3-5 days, volume by air or sea, EXW / FOB Shenzhen / CIF.