Daisy-Chaining Embedded Processors for Enhanced Capacitive Sensor Array Resolution

Capacitive sensing technology is widely applied in ubiquitous sensing. Its low-power consumption enables it to be used in a wide variety of Industry 4.0 applications. Capacitive Sensors can be combined into Arrays (CSAs) with mutual capacitive sensing to reduce external wiring requirements. For instance, the Texas Instruments (TI) MSP430FR2676 can capture and process data from 8×8 capacitive sensor grids. However, it is limited to supporting only 64 sensors. We propose a design incorporating daisy-chaining of CSAs via the I2C serial protocol to enable support for 256 sensors. We also demonstrate a rapid prototyping implementation of 128 sensors. The extended work we plan is to implement the prototype on custom Printed Circuit Boards (PCB) and maximize data update frequency. This architecture can find relevance in industries like manufacturing and farming, enhancing precision in the interaction between robots and huma ns/objects.