Bill of Materials
This page has two sections, Gripper and UMI Robot Wrist, and download links for all their files. Part numbers follow the UMI V4 convention.
Tip: hover over (or tap) an underlined part name to preview its reference image.
Vendor links go to third-party websites, and purchases are made directly with those sellers. NVIDIA receives no commission from them. Product photos of purchased parts belong to their vendors and are not covered by this site’s CC BY 4.0 license.
Download all files
One ZIP per file type for each section, so you can grab everything at once. The ZIPs hold the same files as the tables below.
| Section | STEP (custom CNC) | Drawings (custom CNC) | STL (3D-printed parts) | 3MF (print files) |
|---|---|---|---|---|
| Gripper | — | — | ZIP 29 files · 23.6 MB | ZIP 14 files · 21.0 MB |
| UMI Robot Wrist | STEP 1 file · 0.2 MB | PDF 1 file · 0.3 MB | ZIP 5 files · 1.2 MB | ZIP 5 files · 1.0 MB |
Gripper
Quantities are for one gripper. Step 21 builds the second gripper of the pair, so double everything for a pair.
Filament and print profile
| Filament | Used for | Link |
|---|---|---|
| Bambu Lab PLA Basic | All rigid parts, and the PLA links and mounts of the flexure grip | link |
| Bambu Lab TPU 90A | TPU joints of the flexure grip | link |
| Bambu Lab TPU 95A HF | Fingers (printed on the Bambu Lab P2S) | link |
Print files
| Print file | Prints | Printer | Filament |
|---|---|---|---|
UMI Open Source Printed Parts.3mf | Handle (L and R), flexure grip and the other PLA parts | Bambu Lab H2D | PLA Basic, TPU 90A |
finger.3mf | Two fingers | Bambu Lab P2S | TPU 95A HF |
Both are Bambu Studio projects with the filament and print profile already set. See the print instructions.
3D-printed parts
Print the fingers from finger.3mf and everything else from UMI Open Source Printed Parts.3mf, except the gear, which you add as STL files (print step 4). The STL files are the same parts on their own; hover over an STL link to see its file name.
| Part number | Part | Qty | Material | Files |
|---|---|---|---|---|
| UMI-FLX-ASM-02-0002 | Handle (L or R) | 1 | PLA Basic | STL L · STL R · 3MF L · 3MF R |
| UMI-FLX-ASM-02-0001 | Top cover | 1 | PLA Basic | STL · 3MF |
| UMI-FLX-ASM-02-0008 | Top camera mount | 1 | PLA Basic | STL · 3MF |
| UMI-FLX-ASM-02-0009 | Trigger camera mount | 1 | PLA Basic | STL · 3MF |
| UMI-FLX-ASM-02-0010 | Handle link | 1 | PLA Basic | STL · 3MF |
| UMI-FLX-ASM-02-0003 | Rack | 1 | PLA Basic | STL · 3MF |
| UMI-FLX-ASM-02-0004 | Gear | 1 | PLA Basic | STL · 3MF |
| UMI-FLX-ASM-02-0005 | iPhone 15 Pro holder | 1 | PLA Basic | STL · 3MF |
| UMI-FLX-ASM-02-0006 | iPhone 15 Pro holder clip | 1 | PLA Basic | STL · 3MF |
| UMI-FLX-ASM-02-0007 | VIVE tracker mount (optional) | 1 | PLA Basic | STL · 3MF |
| UMI-FLX-ASM-02-0011 | Flexure grip | 1 | PLA Basic + TPU 90A | STL · 3MF |
| UMI-FLX-ASM-02-0012 | Finger | 2 | TPU 95A HF | STL · 3MF |
Fasteners
Note Qty is the number of single screws or nuts one gripper needs, not the number of packs. Each McMaster link is a pack of 100 screws, so one pack covers every row: a Qty of 14 means 14 screws, which is 1 pack, not 1,400 screws. The Amazon nut links are multi-packs too, so 1 pack of each size is enough.
| Part | Qty (pieces) | Thread | Length (mm) | Part number | Vendor | Link |
|---|---|---|---|---|---|---|
| Hex socket head cap screw | 7 | M3 | 12 | 91290A003 | McMaster | link |
| Hex socket head cap screw | 8 | M3 | 6 | 91290A111 | McMaster | link |
| Hex socket head cap screw | 2 | M3 | 8 | 91290A400 | McMaster | link |
| Hex socket head cap screw | 4 | M3 | 16 | 91290A047 | McMaster | link |
| Hex socket head cap screw | 4 | M3 | 30 | 91290A171 | McMaster | link |
| Hex socket head cap screw | 4 | M3 | 35 | 91290A135 | McMaster | link |
| Hex nut | 21 | M3 | Amazon | link | ||
| Hex socket head cap screw | 12 | M2 | 8 | 91290A015 | McMaster | link |
| Hex socket head cap screw | 3 | M2 | 6 | 91290A013 | McMaster | link |
| Hex nut | 11 | M2 | Amazon | link |
Hex socket head cap screws to ISO 4762 / DIN 912; hex nuts to ISO 4032.
Totals: 29 M3 screws, 21 M3 nuts, 15 M2 screws and 11 M2 nuts, without the VIVE option. The optional VIVE tracker mount (step 18) needs another 4 M3 x 12 mm screws and 4 M3 nuts. Step 11 can use the Phillips screws supplied with the heatsink instead of 4 of the M2 x 8 mm screws.
Electronics
| Part | Qty | Manufacturer | Part number | Description | Vendor | Link |
|---|---|---|---|---|---|---|
| OAK-SoM | 1 | OAKChina | OAKSOM | Part of the OAKChina Data Collection Kit (OAK-NV-KIT) | Arducam | link |
| OAK-SoM heatsink (40 x 30 x 15 mm) | 1 | Included with the OAK-SoM | ||||
| Thermal pad or tape, 12 x 12 mm | 1 | |||||
| UMI-OAK-CB1 main PCB board | 1 | UMI-V4G-PCB-01-0001 | Rev2617; RP2040 runs the firmware | Gerbers | ||
| Top camera (OAK-4P) | 1 | OAKChina | B036801 | Part of the OAKChina Data Collection Kit (OAK-NV-KIT); CAD: UC-760 | Arducam | link |
| Trigger (wide) camera, 8MP USB | 1 | ELP | IMX179 autofocus module | Amazon | link | |
| Rotary encoder board (TLE5012B) | 1 | UMI-V4G-PCB-02-0001 | Rev2617; no firmware needed | Gerbers | ||
| Magnet, 6 mm dia x 2.5 mm | 1 | Radial Magnets | 8995 | Diametrically magnetized | DigiKey | link |
| Cable, encoder board to main PCB | 1 | JST | A05SR05SR30K102A | JST SH, 5-pos, 4.00 in | DigiKey | link |
| Cable, top camera to main PCB | 1 | OAKChina | DF56-26P-250 | Part of the OAKChina Data Collection Kit (OAK-NV-KIT); 26-pin | Arducam | link |
| Trigger camera USB cable | 1 | Included; USB-A end |
The RP2040 on the main PCB runs the gripper firmware. To build and flash it, and for the KiCad files of both boards, see the Firmware tab of the Hardware Guide.
Mechanical and other
| Part | Qty | Manufacturer | Part number | Description | Vendor | Link |
|---|---|---|---|---|---|---|
| MGN9 linear rail, 150 mm | 1 | Sold with a carriage | Amazon | link | ||
| MGN9C carriage block | 2 | May come with the rail | ||||
| Grip tape | 2 pieces | 3M | TB641 | Cut to shape | 3M | link |
| iPhone 15 Pro | 1 | Apple | FTQM3LLIA | Apple | link | |
| Wrist wrap strap with thumb loop | 1 | Fitgriff | GETIEN-0213-1414-114 | Amazon | link | |
| VIVE Ultimate Tracker (optional) | 1 | HTC VIVE | Replaces the iPhone | VIVE | link | |
| ChArUco calibration board | 1 per station | 560 x 360 mm, printed at 100% scale | Print it yourself | link |
Consumables and tools
| Item |
|---|
| Super glue (for example, Gorilla Glue) |
| Grease or lubricant for the gear |
| M2 and M3 hex keys or screwdrivers |
| Filament: PLA Basic, TPU 90A, TPU 95A HF |
| Bambu Lab H2D printer with 0.4 mm nozzles |
| Bambu Lab P2S printer (fingers, TPU 95A HF) |
UMI Robot Wrist
Quantities are for one wrist. Build a second one for a pair. Parts the wrist shares with the gripper have the same part numbers and links as in the Gripper section.
Custom CNC parts
Filament and print profile
| Filament | Used for | Link |
|---|---|---|
| Bambu Lab PLA Basic | Wrist mount, top camera cover, wrist padding and Tianji mount | link |
| Bambu Lab TPU 95A HF | Fingers (print on the Bambu Lab P2S) | link |
Print profile: finger.3mf (Bambu Studio), printed on a Bambu Lab P2S at 50%, Silent. See the print instructions, steps 6 and 7.
3D-printed parts
The fingers print from finger.3mf. The STL files below are in files/mechanical/printed/stl/wrist/, plus the top camera cover and the finger; hover over an STL link to see its file name.
| Part number | Part | Qty | Material | Files |
|---|---|---|---|---|
| UMI-GRP-ASM-02-0005-rB | Top camera cover | 1 | PLA Basic | STL · 3MF |
| UMI-FLX-ASM-02-0012 | Finger | 2 | TPU 95A HF | STL · 3MF |
| UMI-WRST-ASM-02-01 | Wrist mount | 1 | PLA Basic | STL · 3MF |
| UMI-WRST-ASM-02-02 | Wrist padding | 1 | PLA Basic | STL · 3MF |
| UMI-WRST-ASM-02-03 | Tianji mount | 1 | PLA Basic | STL · 3MF |
Fasteners
| Part | Qty | Thread | Length (mm) | Part number | Vendor | Link |
|---|---|---|---|---|---|---|
| Hex socket head cap screw | 8 | M3 | 14 | 91290A600 | McMaster | link |
| Hex socket head cap screw | 4 | M3 | 18 | 91290A121 | McMaster | link |
| Hex socket head cap screw | 4 | M3 | 25 | 91290A125 | McMaster | link |
| Hex socket head cap screw | 4 | M3 | 30 | 91290A171 | McMaster | link |
| Hex nut | 8 | M3 | Amazon | link | ||
| Hex socket head cap screw | 8 | M2 | 8 | 91290A015 | McMaster | link |
| Hex socket head cap screw | 3 | M2 | 6 | 91290A013 | McMaster | link |
| Hex nut | 7 | M2 | Amazon | link | ||
| Hex socket head cap screw | 6 | M4 | 8 | 91290A140 | McMaster | link |
| Hex socket head cap screw | 4 | M4 | 15 | 91290A306 | McMaster | link |
Hex socket head cap screws to ISO 4762 / DIN 912; hex nuts to ISO 4032. All stainless steel.
Totals: 20 M3 screws, 8 M3 nuts, 11 M2 screws, 7 M2 nuts and 10 M4 screws. Step 6 can use the Phillips screws supplied with the heatsink instead of 4 of the M2 x 8 mm screws.
Electronics
| Part | Qty | Manufacturer | Part number | Description | Vendor | Link |
|---|---|---|---|---|---|---|
| OAK-SoM | 1 | OAKChina | OAKSOM | Part of the OAKChina Data Collection Kit (OAK-NV-KIT) | Arducam | link |
| OAK-SoM heatsink (40 x 30 x 15 mm) | 1 | Included with the OAK-SoM | ||||
| Thermal pad or tape, 12 x 12 mm | 1 | |||||
| UMI-OAK-CB1 main PCB board | 1 | UMI-V4G-PCB-01-0001 | Rev2617; RP2040 runs the firmware | Gerbers | ||
| Top camera (OAK-4P) | 1 | OAKChina | B036801 | Part of the OAKChina Data Collection Kit (OAK-NV-KIT); CAD: UC-760 | Arducam | link |
| Trigger (wide) camera, 8MP USB | 1 | ELP | IMX179 autofocus module | Amazon | link | |
| Cable, top camera to main PCB | 1 | OAKChina | DF56-26P-250 | Part of the OAKChina Data Collection Kit (OAK-NV-KIT); 26-pin | Arducam | link |
Mechanical and other
| Part | Qty | Manufacturer | Part number | Description | Vendor | Link |
|---|---|---|---|---|---|---|
| YAM linear gripper | 1 | I2RT | Fingers, finger mounts and wrist mount attach to it | I2RT | link | |
| Robot arm | 1 | The Tianji mount attaches to it (step 11) | ||||
| Grip tape | 2 pieces | 3M | TB641 | Cut to shape | 3M | link |
Consumables and tools
| Item |
|---|
| M2, M3 and M4 hex keys or screwdrivers |
| Filament: PLA Basic, TPU 95A HF |
| Bambu Lab P2S printer |