At my end I have started to build the ‘Core Station’ which will process data from all sensors and transmit them via WiFi. It will be attached to the back of the performer. Based on the research I did, I have decided to upgrade the micro-controller from the previous prototype based on ESP32 to Teensy 4.1. ESP32s are still being used but only for the WiFi connection. Teensy 4.1 contains microprocessor ARM Cortex-M7 clocking at 600 MHz which is in comparison to ESP32’s microprocessor Tensilica Xtensa LX6 clocking at 240MHz significant improvement allowing fast and real-time data transfer from multiple sensors in the same time.

Teensy will be gathering data from two accelerometer sensors GY-521 (MPU6050) attached to the feet, two elbow and two knee stretch sensors and BNO055 (9-DOF absolute orientation sensor) which will be situated in the headpiece. Data from sensors are going to be sent via UART connection into ESP32 WROOM-32U Access Point. I have been considering SPI connection but I struggled to find appropriate libraries at Arduino IDE and learnt that it will require to learn different IDE. I have tested UART which I am familiar with and it proved itself sufficient enough, however I still consider sorting out SPI connection in the future.

On the receiving end there is another ESP32 WROOM-32U which is connected to the computer and sends raw numerical data to the Max MSP. ESP32 WROOM-32U has a specific feature – possibility to attach external WiFi antenna. This significantly improved the data transmission and range.