These are the 3d renders of the 36*36mm 4-layer PCB board for the 4B robot. It contain the CYBLE-022001-00, a tiny ble module in a 10*10mm package. The BNO055 IMU which has an internal fusion block and the VCNL4040M3O as the proximity sensor. Servo connector are all placed around the edge, closer to the servo motors. It also has a vertical usb connector and the MCP73831T LiPo battery charger with a status rgb led in the middle.