ESP8266 – WiFi + Speech Controlled Hexapod Robot

WiFi modules for projects were out of reach for lot of budget hobbyists like me for many years. But things changed when the Esp8266 module from Espressif Systems was released in 2014. Maker community went crazy over this module for the price tag (around $2 for the basic module) and within few months, toolchains, arduino libraries and so many development boards based on Esp8266 started popping up. Esp8266 is a low cost WiFi SoC manufactured by Espressif Systems. It is a 32-bit Tensilica microcontroller with 160KB RAM, support upto external 16MB flash and tons of peripherals like Timer, PWM, UART, I2C, SPI, ADC and so on.

Given the cost of the module, the maker in me couldn’t resist buying at least 4 different Esp8266 modules to experiment with. The community support for Esp8266 was simply superb though I had some troubles with setting the module in boot mode. 

The opportunity to use Esp8266 in a major project came in the form of course project for “Real Time Embedded Systems” at University of Minnesota. So, I teamed up with my colleagues Anand and Gautam and designed a WiFi controlled Hexapod with OLED Display.

• Esp8266 module (I used Esp 201)
• 0.96″ monochrome I2C OLED Display
• 3 x Micro Servo motors
• 2 x LiPo batteries – 3.7V, 500mAh
• General Purpose PCB
• Acrylic Sheet ( For chassis)
• Legs – Steel Wires (salvaged from restaurant TO-GO boxes)
• Hot Glue Gun
• Electric Driller/Cutter

The Android application receives commands via buttons and speech inputs and translates them to HTTP requests. These requests are received by the web server running in the ESP8266 module which controls the servos and OLED Displays. The eyes blink when idle and they turn and “see” left when a left command is received through button press or speech or any other direction command. The video demo below shows most functionalities of the Robot.