LOFI Robot Do It Yourself version
Construction
LOFI Robot provides a set of lasercut wooden blocks to start building your robot. You can find building manual and link for design files HERE or on Instructables. If you have access to a lasercuttter (maybe you can find one available in your local makerspace or fab lab) and some vector drawing software such as free AutoCad360 you can easily modify the parts to use it with Arduino board and breadboard on top.
Without the lasercut part still it shouldn`t be too complicated to build a two-wheel robot from scratch. Find some plastic or wooden plate to mount dc motors and arduino on it, use some duck tape, zip ties, your imagination and you are almost there.
If you are into 3D printing you can find plenty of 3D printed robot chasis on the web.
Electronic parts list
- Arduino Leonardo or UNO - or in fact any other Arduino compatible board
- Breadboard
- Jumper wires
- 2 x geared DC motor
- L293D - dc motor driver
- HC-SR04 distance sensor
- Bluetooth module - most popular HC-05, HC-06 bluetooth 2.0 modules or HM-10 BLE module for iOS
- Buzzer
- Some kind of power supply - 4xAA battery pack or a powerbank
Electronics schematics
INPUTS and OUTPUTS
Four analog inputs and four analog outputs in LOFI Blocks are related to Arduino pins as follows:- INPUT1 - A0
- INPUT2 - A1
- INPUT3 - A2
- INPUT4 - A3
- OUTPUT1 - D10
- OUTPUT2 - D9
- OUTPUT3 - D6
- OUTPUT4 - D5
DC motors
To supply power and direction control to DC motors we use an L239D motor driver.
Connect it to Arduino board as follows:
- ENABLE1 - D3
- INPUT1 - D4
- OUTPUT1 - DC motor 1-1
- GND - GND
- GND - GND
- OUTPUT2 - DC motor 1-2
- INPUT2 - D2
- Vs - 5V
- ENABLE2 - D5
- INPUT3 - D7
- OUTPUT3 - DC motor 2-1
- GND - GND
- GND - GND
- OUTPUT4 - DC motor 2-2
- INPUT4 - D8
- Vss - 5V
Bluetooth
We use bluetooth for mobile communication between the app and arduino board
On Android LOFI Blocks communicates with bluetooth 2.0 (classic) modules such as HC-06 or HC-05 or any other similar module. BLE support on Android is on the way!
On iOS the app communicates with HM-10 and HM-11 bluetooth LE modules, depending on their UUID, service and characteristics IDs, so by now it will not work with other BLE modules. If you needto use a different BLE to Serial module it might be possible to change its UUID and characteristics to mimic HM-10.
LOFI Brain firmware uses serial speed 57600 bauds to communicate with bluetooth module. Most bluetooth modules have the default speed set to 9600 bauds so keep in mind to change it with ATcommands or modify the firmware.
Connections (bluetooth - arduino):- Vcc - 5V
- GND - GND
- TX - RX
- RX - TX
Distance sensor
The most popular HC-SR04 ultrasonic distance sensor is used for for basic object detections and object avoidance.
Connections (HC-SR04 - arduino):- Vcc - 5v
- Echo - D11
- Trig - D12
- GND - GND
Buzzer
Simple on/off buzzer is used as basic sound actuator.
Connections (buzzer - arduino):- Signal - D13
- GND - GND
