AT42QT1011 Capacitive Grip/Touch Sensor PCB

AT42QT1011-based capacitive grip/touch sensor PCB work for industrial gripper applications, designed in KiCad and fabricated in-house on an LPKF S63.

1. Overview

This project documents the capacitive grip/touch sensing hardware I developed at As Robotics (COMAU Turkey) for industrial gripper applications. The prototype is built around the Microchip AT42QT1011 and was designed to provide a compact digital touch signal that could be integrated into a robot end-effector.

The main motivation was practical: the intended sensor IC was not available locally in Turkey, so I sourced an AT42QT1011, adapted the circuit around the available component, and produced the PCB in-house.


2. What I did

  • Designed the schematic and layout in KiCad for an AT42QT1011-based capacitive grip/touch sensor
  • Implemented a compact reference-style front-end with tuning/RC parts, decoupling, and a simple output header
  • Fabricated the board in-house using an LPKF S63 and hand-soldered the SMD components
  • Integrated the PCB into a robot end-effector as a capacitive sensing prototype for gripper interaction
  • Used the build to strengthen the full PCB workflow from schematic capture to fabrication and bench testing

3. Circuit (brief)

The AT42QT1011 drives a charge-transfer capacitive measurement between SNS and SNSK. The external pad connects via R1 (10 kΩ) and forms the sense electrode; C2 (10 nF) between SNS/SNSK tunes the charge-transfer timing. C1 (0.1 µF) decouples VDD. The IC outputs a digital OUT when touch is detected. The header exposes PAD, OUT, VCC, and GND for easy integration.


4. Images and media

Schematic

Minimal reference design: AT42QT1011 with R1, C1, C2, and 4-pin header (PAD, OUT, VCC, GND).

PCB layout

Single-layer routing and component placement for the compact board.

PCB renders

3D renders from KiCad before fabrication.

Soldering

Hand-soldering SMD components on the bare PCB.

Final assembly

Capacitive grip/touch sensor integrated into the robot end-effector.

Videos

LPKF S63 PCB fabrication.

Touch sensor testing.