make_parkstop

Objectives

• To build a parkSTOP device to visually indicate via LED if parking position is reached.
• In addition, indicate via Android App, comunicating via Bluetooth, the actual distance and if parking position reached.
• Usage f.e. to park in the garage for cars without parking distance sensors or park at an exact position.

Functionality

• ParkSTOP Device: Indicate position LED RED = reached Stop distance, YELLOW = reached Warning distance (=1.5 times stop distance), GREEN = reached between notify distance and warning distance.
• ParkSTOP Device: Alarm (via Buzzer) when reaching warning or stop distance.
• ParkSTOP Device: Store settings (in EEPROM).
• Android App: Show distance, indicator meter with bar to see position, indicate to stop, set stop-/ notify distance and if buzzer on.
• Communication via Bluetooth between the devices e.g. ParkSTOP device and Android App.
• Open to connect other Bluetooth devices (but only one at the time).

Creation Rules

• Use as microcontroller an Arduino UNO.
• Use standard LEGO bricks.
• Minimize LEGO brick modifications.
• LEGO Case with modular components.
• Build code with B4R and B4A.

Hardware Parts (approx cost EUR)

• 1x Arduino UNO (8 EUR)
• 1x HC-05 Bluetooth Adapter (7 EUR)
• 1x HC-SR04 Ultrasonic Distance Sensor (2 EUR)
• 1x Buzzer (1.75 EUR)
• 3x LED (0.75 EUR)
• In addition for the prototype: Breadboard (2 EUR)
• LEGO bricks [LEGO is a trademark of the LEGO Group] (10 EUR)

Software

• Arduino IDE 1.8.0
• B4R v1.80
• B4A v6.50 (Min software versions required)

Wiring

#Arduino = Buttons (WireColors)
#Bluetooth
HC-05 = Arduino
VCC = 5v (red)
GND = GND (black)
TX = 10 Receive Pin (green)
RX = 11 Transmit Pin (yellow)

#Distance
[CODE]HC-SR04 = Arduino
VCC = 5v (red)
Trigger = D8 (blue)
Echo = D7 (white)
GND = GND (black)

#Indicators
LED RED = STOP
LED = Arduino
Anode (+) = D4
Cathode (-) = GND
LED YELLOW = WARNING
LED = Arduino
Anode (+) = D5
Cathode (-) = GND
LED GREEN = OK
LED = Arduino
Anode (+) = D6
Cathode (-) = GND

#Buzzer
Signal = D12 (red)
GND = GND (black)

Soure Code

The B4R source code and required libraries can be found in archive parkstop.zip. The code is well documented.