Hermit assembly

One Hermit is assembled from printed parts, one STS3215 7.4 V servo, one camera, one Waveshare servo board, a UMI marker, and marker tiles. The places where the servo, jaw, and camera attach are the same as on the arm’s gripper. The left and right hands are mirror images of each other, so the order is the same.

Left handRight hand

Drag to rotate · Ctrl + scroll to zoom

1 / 10

1. 1body

   The handheld body is the frame of the Hermit. It has a tunnel under the fixed blade for the index finger, and a roof above it that carries the UMI marker.

2. 2Camera nuts

   Push an M3 hex nut into each of the 2 nut slots on the inside of the body's claw side face. The servo of the next step closes the slots, so put the nuts in before the servo. These nuts take the M3×10 bolts that hold the camera bracket.

   • M3 hex nut×2body nut slot
3. 3Servo

   Fit the horns on the STS3215 7.4 V servo and fix the top horn with its centre screw, then put the servo in the servo seat of the body and fix it with 2 screws on each side. This servo is not driven; it only reads the angle the jaw is opened to.

   • M3×6×1Top horn, centre
   • M2×6×4Servo → body
4. 4jaw

   Fix the handheld jaw to the servo horn with a horn screw. The screw-head seats are on both faces of the jaw. The thumb goes into the tunnel under the jaw and opens and closes the jaw together with the index finger.

   • M2.5×8jaw → horn
5. 5Camera

   Remove the four corner screws of the AR0234 camera module and fix the module to the camera bracket with 4 M2 screws long enough to pass the front wall of the bracket. Fix the bracket to the claw side face of the body with 2 bolts, which go into the nuts placed earlier. The camera sits in the same place as on the arm.

   • M3×10×2camera bracket fixing
   • M2×4Camera module → bracket
6. 6peg

   Push the peg all the way into the square hole under the body's roof. It fits tightly without screws, and being square it keeps the UMI marker from turning on the peg.

7. 7UMI marker

   Push a marker tile into each face of the UMI marker, then push the marker's socket all the way onto the peg. One empty face touches the roof, and another empty face points toward the hand.

8. 8board mount

   Fit the board mount onto the empty face of the UMI marker that points toward the hand.

9. 9driver plate and servo board

   Fix the Waveshare Bus Servo Adapter (A) to the driver plate with 4 screws and fit the plate onto the board mount. The screw heads sink into the face of the plate that fits in. Leave the board's jumper on the USB-Servo side.

   • M2.5×4driver plate fixing
10. 10Cables

    Connect the servo to the servo board, and connect the board's USB-C and the camera's USB to the host. The board's USB-C does not power the servo, so feed 5 V separately through a USB to DC5521 cable.

• Servo ids and the jaw calibration are done after assembly, in Setup.
• Print the marker tiles in white and black and fit them into the faces of the UMI marker.

Screws

The count is the sum of the screws used in each step.

Screw	One Hermit	Pair (2)
M3 hex nut	2	4
M3×6	1	2
M2×6	4	8
M2.5	12	24
M3×10	2	4
M2	4	8