About Our Robot

The CoderDojo robot is built around a set of low-cost components that are designed to be open and extensible. Version 3 has the following components.

  • 2 DC motors
  • chasis
  • Arduino compatable nano
  • motor controller based on L293D
  • 400 connection point solderless breadboard
  • Ultrasonic distance sensor
  • Addresible LED strip

Our design goals in this platform it to be a platform to teach the fundamental principals of robots and control systems.

This platform is designed to support the following learning labs.

  • using the Arduio and the motor control to turn a motors on an off
  • using Pulse Wave Modulation (PWM) to control motor speed
  • changing motor direction
  • controlling two motors
  • reading data from a sensor and estimating object distance
  • displaying information on an LED strip
  • basic obstacle avoidance

We should note that we are using Arduino Nano that uses a CH340 serial driver. This driver should be downloaded before you start up your Arduino software.

You can install the CH340 driver from this web site:

http://www.wch.cn/downloads.php?name=pro&proid=5

(yes, the site is in Chinese but you can just and then look for the "English" words to download the Windows or mac driver)

Note for Mac Users

Some of the latests versions of the Mac add a special security feature that only allows "signed" "kext" (kernel) drivers. Our driver has not yet been signed. If you have a recent Mac you may need to take the following additional steps

Open the Application/Utilities/Terminal application and enter the following text:

   sudo nvram boot-args="kext-dev-mode=1"

Next, reboot your Mac.

If the drivers are installed correctly you should see two addional items in your Tools -> Serial Port menu. One will be for /dev/tty.SerialPort and the other for /dev/cu.SerialPort. If you do not see these items your driver may not be installed correctly.

Note that this command disables the additional check for a signed driver. If you are downloading any files from unknown sources you should re-enable these checks when you are done using the Arduino application and then reboot your system again.