4 layers75 × 35 mm
LASK5-V3-0
Open-Muscle/OpenMuscle-LASK5
Handheld labeler wand for training ML models on gesture inputs
56 parts3CERN-OHL-S-2.0
2 layers27.5 × 52 mm
OM EPSC3-Micro
turfptax/OM-Dev-Kit2Open Muscle Dev Kit (V0/V1): ESP32-C3 sensor-cell hardware (KiCad PCBs + gerbers) and MicroPython firmware for the OpenMuscle pressure-sensing platform.
- Size
- 27.5 × 52 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 23
- Nets
- 25
- Pads
- 75
- Tracks, vias
- 175, 20
- Pours
- 4
- Routed
- Yes
- KiCad
- KiCad 7 (file 20221018)
- Created
- 17 Apr 2024
- Updated
- 8 Jun 2026
Overview
OM EPSC3-Micro is an open-source printed circuit board by turfptax, from the turfptax/OM-Dev-Kit repository on GitHub. It is a 2-layer board of 27.5 × 52 mm with 23 parts on 25 nets, routed with 175 tracks and 20 vias.
It is built around the LTC4054ES5-4.2#PBF and TPS7A03DQN. Its parts include 5 capacitors, 5 connectors, 3 resistors, 3 ICs and 1 diode. It belongs with the sensors and measurement boards and the ESP32 boards of this library.
Main components
2README
README.mdOpenMuscle Dev Kit
Hardware and firmware for the OpenMuscle Dev Kit (V0/V1), the bench platform used to prototype and validate OpenMuscle's pressure-sensing cells before they go into wearable arrays like FlexGrid.
Part of the OpenMuscle open-source neurotech ecosystem. See openmuscle.org for the project background.
What's here
Micropython/ MicroPython firmware, organized by sensor cell
Cell 00 .. Cell 05 Per-cell code
Open Muscle Dev Kit V0 Cell Numbers Addresses.xlsx Cell -> I2C/bus address map
PCB/ KiCad hardware design
OM-EPSC3-Micro.* ESP32-C3 micro controller board (schematic, layout, 3D)
OM-DEV-Kit.* Dev kit carrier board
OM-ESPC3-Micro-Gerb/ Fabrication gerbers
OpenMuscleDevKit.pretty/ Custom KiCad footprint library
TRRS Footprint/ TRRS connector footprint (single-wire power + data)
*.svg Edge-cut and artwork exportsHardware at a glance
- MCU: ESP32-C3 (
OM-EPSC3-Microboard) - Sensing: multiple addressable pressure-sensing cells (see the cell address spreadsheet)
- Interconnect: TRRS connector for chained power + data between cells
- CAD: KiCad project files, gerbers, and STL included for fabrication
Firmware
Each Cell NN directory holds the MicroPython for one sensor cell. The accompanying spreadsheet maps cell numbers to their bus addresses so a host can poll the array. Flashing and OTA follow the same pattern as other OpenMuscle devices via ugit.
Status
This is an early dev-kit snapshot (V0/V1). It is preserved as a reference design; active sensor development continues in the OpenMuscle organization.
License
See the OpenMuscle project for licensing.
Parts
23| Qty | Value | Footprint | References |
|---|---|---|---|
| 2 | 100 nF | Capacitor_SMD:C_0402_1005Metric | C1, C2 |
| 2 | 4.7uF | Capacitor_SMD:C_0805_2012Metric | C9, C10 |
| 2 | A1369xUA-10 | OpenMuscleDevKit:Hall49E | H0, H1 |
| 2 | Conn_01x02_Pin | Connector_PinHeader_2.54mm:PinHeader_1x02_P2.54mm_Vertical | J2, J3 |
| 2 | SolderJumper_2_Open | Jumper:SolderJumper-2_P1.3mm_Open_TrianglePad1.0x1.5mm | JP1, JP2 |
| 1 | 150 | Resistor_SMD:R_0603_1608Metric | R2 |
| 1 | 1K | Resistor_SMD:R_0603_1608Metric | R8 |
| 1 | 2.2 uF | Capacitor_SMD:C_0603_1608Metric | C5 |
| 1 | 2.7k | Resistor_SMD:R_0603_1608Metric | R1 |
| 1 | Conn_01x01_Pin | Connector_PinHeader_2.54mm:PinHeader_1x01_P2.54mm_Vertical | J5 |
| 1 | Conn_01x04_Pin | Connector_PinHeader_2.54mm:PinHeader_1x04_P2.54mm_Vertical | J1 |
| 1 | JST_02 | Connector_JST:JST_EH_B2B-EH-A_1x02_P2.50mm_Vertical | J4 |
| 1 | LED GREEN | LED_SMD:LED_0805_2012Metric | D1 |
| 1 | LTC4054ES5-4.2 | Package_TO_SOT_SMD:TSOT-23-5 | U2 |
| 1 | SW_Push | OpenMuscleDevKit:EVQP2P02M | SW2 |
| 1 | TPS7A03 | Package_TO_SOT_SMD:SOT-23-5 | U5 |
| 1 | ~ | Package_TO_SOT_SMD:SOT-23-6 | MAX1 |
| 1 | ~ | OpenMuscleDevKit:ESP32-C3-Super Mini | U1 |
Questions
How big is the OM EPSC3-Micro PCB?
It measures 27.5 × 52 mm and has 2 copper layers, 1.6 mm thick.
What parts does the OM EPSC3-Micro use?
23 parts, built around the LTC4054ES5-4.2#PBF and TPS7A03DQN. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the OM EPSC3-Micro KiCad files?
From the turfptax/OM-Dev-Kit repository on GitHub, at the commit this page was made from: the board is PCB/OM-EPSC3-Micro.kicad_pcb and its schematic PCB/OM-DEV-Kit.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the OM EPSC3-Micro design in my own project?
Its repository states no licence, so its author keeps all rights: ask turfptax before reusing the design.
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