Geekcreit DIY NodeMCU Lua 4WD Open Source ESP8266 ESP-12E WiFi Smart Car Kit
A part of the review has been auto-translated.
At 25x15x~8 cm it is no small RC car; which has lots of space to mount sensors and shields and battery cases. The only problem is that these are not provided. it has 4 speed encoders (one for each wheel) but not a single photoelectric sensor to make those encoders useful. The hardware and software are open source and the documentation *online* is provided in English although maybe not too clear but very useful. enclosed instructions are only for the chassis and no instructions are provided for the wiring. The shield provides pins to attach sensors to (but no sensors are provided). Testing the components out of the box is as simple as attaching a power source (which is not provided either). I powered it with 4 AA batteries (~6v common power source) which didn't provide enough power for the motors to move the car over the rug but the shield does accept up to 36v power source for the motors and up to 9v to power the controller Which translates 9v max for common power source - when Vin and Vm are connected via jumper). There is an On/Off button on the shield but it doesn't seem to work when the power selection jumper is attached to the board. I got the blue chassis since I didn't notice there was a transparent option. maybe I should buy another one then?!