Testing electronic modules
15 June 2016
– LOFI BRAIN Arduino-compatible controller with SENSORS TESTING script flashed in
– Sensros: potentiometer, light sensor, button, distance sensor HC-SR04
– Actuators: LED, DC motor
Upload Sensor testing script to LOFI Brain`s Arduino.
Test no. 1 – Light sensor + LED
LIGHT SENSOR (PHOTORESISTOR) connected to INPUT1
LED connectet to OUTPUT1
How it works:
Depending on the ammount of light detected by the light sensor the LED shines with a corresponding brightness. If you cover the light sensor with your hand the LED will turn off (almost) completely.
Test no. 2 – Button + LED
BUTTON connected to INPUT2
LED connected toOUTPUT2
INPUT2 is programatically connected with OUTPUT2 but the signal from INPUT one is reversed – maximum value on INPUT2 gives ZERO value on OUTPUT2.
Test no. 3 – Distance sensor HC-SR04 + buzzer
DISTANCE SENSOR plugged into it`s LOFI Brain socket.
Buzzer gives pulsing squeacky sounds with tempo corresponding to the distance measured by HC-SR04 distance sensor.
Test no. 4 – Potentiometer + voltage meter + DC motor
POTENTIOMETER connected to INPUT4
VOLTAGE METER connected to OUTPUT4
DC MOTOR connected to M2
Value measured by INPUT1 is directed to M1 mototr controller output and OUTPUT4
LOFI Brain is the main controller of robots built with EDUBOX kit. It is not called that way without purpose. If we compare a robot to a living organism (some animal for example) a controller in a robot does exactly the same job as a BRAIN in any living body.
What are controller main functions:
– reading signals from SENSORS (robot`s senses)
– controlling ACTUATORS – motors, leds, buzzer, or any other instruments that let your robot ACT
– communicating with computer (or mobile device) – talking to a BIGGER computer/brain
– executing programs
Technically speaking our LOFI Brain board is a so called adapter to an Arduino-compatible microcontroller. Arduino does all the computing while the adapter board makes connecting power, sensors and actuators simple by using one universal JST connector. You can easily power up your robot from anything USB (computer, smartphone charger or powerbank) and connect DC motors, servos, bluetooth and some other modules on the fly to build your first robot in minutes.
LOFI BRAIN main elements:
- 1. PRO MICRO module – Arduino Leonardo compatible
- 2. Four INPUT connectors – four white connectors on the left side of the board for reading sensor data provided by LOFI modules (light sensor, button, potentiometer)
- 3. Four OUTPUT sensors – four white connectors with analogue output to control actuators such as LED, voltage meter or servo motors, they can also drive the DC motors but only in one direction and with very little load
- 4. Buzzer – little built-in speaker that lets your robot give simple squeaky sound signals
- 5. BLUETOOTH connector – compatible with the most popular bluetooth 2.0 (HC-05, HC-06) and blueotooth 4.0 (HM-10) modules
- 6. HC-SR04 distance sensor connector
- 7. L293D motor driver – built-in DC motor driver lets you turn motors and change their directions
- 8. DC motors connectors – two black connectors labeled M1 i M2 for powering up DC motors
- 9. ON/OFF switch – works when the board is powered by built in micro-USB connector (not the one on the Arduino Pro Micro module)
LOFI Brain is powered via micro-UCB port with a powerbank or any other USB power source (computer, mobile device charger).
If the board is connected to computer by PRO MICRO (Arduino) USB port, connecting additional power to LOFI Brain USB port is not necessary, ON/OFF switch will not work then (robot will be always ON)
If the robot works autonomously powered only with powerbank connect it to the LOFI Brain USB port (not the PRO MICRO one)
All LOFI Brain electronic modules (light sensor, button, potentiometer, led) are being connected to the controller with a 3-wire cable with an universal JST connector.
Modules are divided into two basic categories:
SENSORS – light, button, potentiometer
Actuators – led, voltage meter, DC motor, servo motor
SENSORS are being conected to INPUT 1-4 while ACTUATORS are being connected to OUTPUT 1-4 except of DC motors which are being connected to M1 and M2 sockets
WARNING! – while plugging JST connector to INPUT/OUTPUT socket pay attention to putting it in right direction – JST plug has three metal blades on one side – plug them facing the plastic bolt of the socket
BLUETOOTH module connection
LOFI Brain is compatible with the most popular bluetooth modules widely used in Arduino community – bluetooth 2.0 (HC-05, HC-06) and bluetooth 4.0 (HM-10)
Connecting Bluetooth module:
WARNING – pay attention to plugging the bluetooth module in the right direction otherwise it might get damaged
– bluetooth 2.0 – Android 2.3 and up, App Inventor, most desktop and laptop comuters, easy to use serial interface
– bluetooth 4.0 – iPhone 4s and up, iPad 3 and up, Android 4.3 and up, little compatibility with desktop and laptop computers
LOFI Brain controller can work in two main modes:
1. Controlled by host (desktop or mobile) – eg. when working with Scratch – main program is executed on the host computer and only specific instructions are passed to the Arduino microcontroller which acts as a puppet on the strings.
2. Autonomuous mode – main program is uploaded to the Arduino and executed “on the robot” without any dependency to external hardware like in the example with obstacle avoiding robot. In that mode robot can still comunicate with wither devices (for example can be controlled via bluetooth with a mobile device)