What it is
The arm has six joints and a parallel gripper. The links are flat aluminium plates, laser-cut and bolted to the side of each joint module. Plates are cheap to cut in small batches, and a new version needs only a new drawing, not new tooling.
Each joint module holds a motor, gearbox, encoder and driver in one housing. We buy them from Damiao instead of designing our own, so the first arms can be built now. All six joints share one CAN bus, and you drive them from Python on your own computer.
First build
| Base, shoulder, elbow | 3 × Damiao DM-J4340P-2EC |
|---|---|
| Wrist | 3 × Damiao DM-J4310-2EC |
| Gripper | Feetech ST3215 servo, 12 V |
| Links | Laser-cut aluminium plate, made in Europe |
| Connection | A USB adapter for the CAN bus and the gripper's serial bus |
| Reach and payload | Published after we test the joints under load |
Where we are
The design on this page is a concept model. Before we cut any plates, we put one shoulder joint and one wrist joint on a test rig with a weight at full reach. That tells us how much the arm can lift, how warm the joints get and how much the links bend. After that we order the first plates, build a full arm and run a partner's task on it.
We would also like the arm to sense force at each joint. That needs a torque sensor on the joint output, and we will write about it here once we have measured one.
Work with us
Labs and integrators
Tell us one task you want an arm to do and how you would check that it works. We agree the setup and a price for the pilot, build the arm and test it against your check.
Metal shops
We need someone to review the link plates and quote the first batch. The work is laser cutting, some bending and a few small machined parts.
The Komatachi Arm is in development. The model and drawings on this page show the concept and are not a manufacturing design. Damiao and Feetech make the joint modules and servo we use. Komatachi is not affiliated with either company.