Electrical

Power

The hand requires 24 VDC for full functionality. It will work at lower voltages (down to about 12 volts), but with reduced finger speeds.

It draws about 0.4 to 0.5 amps with all fingers powered and idling. When all fingers are driving, it will draw about 2.5 amps.

Connectors

The external interface to the hand is just power and gigabit Ethernet. The power connector is a 2-pin Molex Micro-Fit inline header. The mating connector housing is Molex #0436450200, Digikey #WM1845. There are many options for the terminals, but I have had success with Molex #0430300008, Digikey #WM2773. The official crimper is Molex #0638190000, Digikey #WM9022, and it is awesome, but expensive. Jameco #99443 is much much cheaper, and I've used it with varying degrees of success for just doing one or two crimps. If you're a klutz like me, you'll also want to buy a connector extractor tool like Jameco #338669 for when you gank up a terminal inside a housing.

Schematics

The Sandia Hand electronics are an open source hardware project as described by the Open Source Hardware Statement of Principles and Definition v1.0. The electrical designs are released under the FreeBSD Documentation License. These links are PDF exports of the schematic files.

• Hand frame motherboard (mobo)

• Right palm tactile array (rpalm)

• Left palm tactile array (lpalm)

• Finger motor control board (fmcb) (these were done with an older CAD program, and thus aren't as nice-looking)

• Proximal phalange tactile array (f2)

• Distal phalange tactile array (f3)

• Palm camera (cam)

• Right hand frame connector-board (right_conn)

• Left hand frame connector-board (left_conn)

PCB Layouts and native Schematic files

These layouts are provided in Altium Designer, with the exception of fmcb, which was done in GNU PCB. These archives include the Altium schematic files as well as the layouts.

• Palm motherboard (mobo)

• Palm stereo camera (cam)

• Right palm (rpalm)

• Left palm (lpalm)

• Right palm connector-board (conn)

• Left palm connector-board (conn)

• Distal phalange (F3)

• Proximal phalange (F2)

• Finger motor controller board (fmcb)

• Finger pogo connector board (finger_pogo)

Tactile Sensor Locations

• Right Palm tactile array

• Left Palm tactile array

Random notes

• finger temperature sensors: first element of the finger_N/raw_state/fmcb_temp is a Microchip MCP9804

• motor driver chips: ST L6229Q datasheet