revanth kailashnath
Contributors:
- Revanth Kailashnath. https://github.com/p4nd4m01um
- Jinyu Cao. https://github.com/Cao-Jinyu
- Hao Ding. https://github.com/kenzo0619
We are a team of three devoted to completing the project to help humans reduce their efforts in facing the challenges of life. Cuz lets face it (pun intended!), as humans, we got bigger things to worry about :)
Anti-Icing System
Problem:
During cold winters, the footpaths and driveways in houses build up ice and frost, thus making it slippery. Lots of accidents happen to occur due to this ice build-up. So we thought of a device which would prevent people from falling down and breaking their hips.
Solution:
Ant-icing device is an automatic RPi based system which distributes brine water on the footpaths, thereby lowering the freezing temperature of water and also causing ice which has already formed to melt. The brine water referred here is 25% salt and 75% water.
Hardware:
- Seeed AM2302/DHT22 digital temperature & RH sensor.
Measures ambient temperature and relative humidity (RH). AM2302 is a high accuracy wired counterpart of the DHT22 sensor. _It can work in extreme environmental conditions. _ It has amazing accuracy. RH ±2%. Temperature ± 0.5⁰C. It utilizes as 40-bit data stream = 16-bit RH data+ 16 data temperature data + 8-bit checksum data.
- HC-SR501 passive infrared (PIR) sensor
Detects motion. Range: arc radius < 110⁰. Distance < 7m. Operating temperature: -15⁰C to +70⁰C.
- QR50E Brushless DC Motor Pump.
Manufacturer: Decdeal. Pump capacity: 280l/hour. Rating: 5W, 12V.
Connections:
We use WiringPi numbering in our code, hence:
power GPIO: 4.
motor GPIO: 3.
PIR sensor GPIO: 0.
DHT22 sensor GPIO: 7.
Working:
The AM2302 sensor detects the ambient Temperature and Relative Humidity. These variables are then used with the equation illustrated below:
Where,
T = ambient temperature.
The ambient Relative Humidity is compared with RHthreshold. If it is lower than the threshold value, then there is a definite chance of precipitation. Alternatively, we can also find the melting temperature of snow and determine the probability of precipitation (POP).
If POP is higher than the critical value we set, then the motor pump is made run. Thus, pumping the brine water which is stored in a container like a sump or a barrel.
The motor control is enabled through a transistor (TIP 121) switch and a freewheeling diode combination (1N4004). It has to be noted that the motor has its own power supply.
The PIR sensor is used to sense motion around the device. In the event that detects movement, the operation of the device is interrupted. This is done as nobody wants to get hosed down by salt water and have their day ruined.
Software:
The sensor codes are implemented onto the Raspberry Pi using a combination of C and C++.
The sampling rate of RH & T sensor is about 0.33 Hz (3 seconds). The PIR sensor has a sampling rate of 1 Hz (1 second).
Granting, this is just a design choice which can be changed in later versions should such needs arise.
The data collected from the sensors are written onto a database written using the open source database management system, MySQL.
A web-server is used to display the temperature and humidity. The web-server is written in PHP using jQuery, Ajax which is short for asynchronous JavaScript and XML. It reads data from the database every second (which doubles up as the refresh rate of the website).
Advantages:
-
Reliable
-
User friendly
-
Robust and flexible
-
Safe
Disadvantages:
- Brine water requires storage and it has to be periodically restocked manually.
Future Scope and Versions:...
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Cedric
Rohan Menon
kijani grows
