A pills counting system based on the capacitive sensor

To help the cerebropathy patients and old people to count pills they have taken, a weighing capacitive sensor system is designed. Polydimethylsiloxane (PDMS) material is utilized to make springs between capacitive sensor plates. To convert the capacitance signal to the voltage signal, a circuit for small capacitance measurement is devised. Experiments show that the number of the pills from 0 to 100 can be measured by the proposed capacitive sensor accurately.