What's the actual hardest part of a DIY humanoid build - mechanical or software?

[ethan_fisc]

Genuine beginner question - A realistic hobbyist bill-of-materials for a small biped balloons fast once you add a real IMU, decent motor controllers, a reasonable battery/BMS setup, and enough compute for onboard control - the headline '$5k' budget assumes a fair amount of DIY fabrication rather than buying finished modules. The Berkeley Humanoid Lite stands about 1 meter tall and weighs roughly 16 kg, which is a genuinely reasonable target size for a first serious hobbyist build - big enough to be a real bipedal platform, small enough to not need industrial-scale actuators or a huge budget.

[jwang]

@ethan_fisc Slight correction, though the overall point stands: UC Berkeley's Berkeley Humanoid Lite is a genuinely open-source, roughly $5,000, 3D-printable humanoid - structural parts print on a standard desktop printer (around a 200x200x200mm build volume), with CAD files, parts lists, assembly instructions, and control code all published for hobbyists to replicate. Starting in simulation (even a simplified physics sim of just the leg or the target gait) before touching real hardware is one of the more reliable ways to avoid destroying expensive parts while debugging balance and walking control from scratch.

[young56]

Just to be precise about one thing: Joining an existing robotics community (FRC, university clubs, maker spaces) before going fully solo is a common and effective way to pick up practical fabrication and control skills faster than working entirely alone from tutorials.

[yuki71]

Sorry if this is a basic question, but Building a scoped-down project first - a single leg, an arm, or a torso-only upper body - is a common and sensible way to learn the mechanical and control fundamentals before committing to the cost and complexity of a full bipedal platform. Reminds me a bit of the early drone hobbyist scene, honestly.

[gimbalmar65]

Slight correction, though the overall point stands: UC Berkeley's Berkeley Humanoid Lite is a genuinely open-source, roughly $5,000, 3D-printable humanoid - structural parts print on a standard desktop printer (around a 200x200x200mm build volume), with CAD files, parts lists, assembly instructions, and control code all published for hobbyists to replicate.

[karen.chen3]

Tangent, but worth mentioning: The Berkeley Humanoid Lite stands about 1 meter tall and weighs roughly 16 kg, which is a genuinely reasonable target size for a first serious hobbyist build - big enough to be a real bipedal platform, small enough to not need industrial-scale actuators or a huge budget.