Prof. J. Walter - Informationstechnik, Mikrocomputertechnik, Digitale Medien Advantages - Disadvantages - Catalogue
Hochschule Karlsruhe Logo Bachelor-Thesis
IOT for Home Automation by Browser
Winter Semester 2018/2019
Ong Kai Li (65631)

3.4 Advantages - Disadvantages - Catalogue

Solution Components

A Sub-Function: Power supply
A.1 - Rechargeable Battery
 
Rechargeable Battery [Source]
Advantages: Disadvantages:
It is portable which allow user to carry the switched on system to anyway. The energy cannot last for long time.
It is still useable when blackout. It cannot be used in the device with higher voltage.
   
   
   
 
A.2 - AC Plug-in
Figure 3.4.1 : Type G Plug
Advantages: Disadvantages:
The energy can last for long time. It cannot use when blackout.
It can be use for the devices with higher power. It is not portable which user cannot carry to anywhere when the device is on.
   
   
   
A.3 - DC Power Adapter
Figure 3.4.2 : DC Power Adapter
Advantages: Disadvantages:
The energy can last for long time. It cannot use when blackout.
It can be use for the devices with DC power. It is not portable which user cannot carry to anywhere when the device is on.
It is safer than AC power supply.  
   
   

B Sub-Function: Brightness detect
B.1 - BH1750 Light Intensity Sensor
 
BH1750 Light Intensity Sensor [Source]
 
The BH1750 is one of the most advanced light intensity sensors that can be use to measure the light. The output of this sensor is value of light in Lux (Lx), and this sensor can give an accurate output without making any calculation by user.
 
Maximum Voltage (Vmax) 4.5 V DC
Operating Voltage (V) 2.4 V ~ 3.6 V DC
Operating Temperature (°C) -40 °C to +85 °C
Range of Sensor (lx) 1 lx to 65535 lx
Sensitivity (lx) High Resolution : 0.5lx ~ 1 lx
Low Resolution : 4lx
Cost (€) 11.65 €

 
Advantages: Disadvantages:
It has high sensitivity. It has higher cost.
It has faster measure time. (High resolution: 120ms) It has smaller range of operating temperature.
The Inter- integrated Circuit (I2C) is available in this light intensity sensor.  
   
   

 
B.2 - Light Dependent Resistor Sensor Module (LDR Sensor Module)
Figure 3.4.3 : Light Dependent Resistor (LDR) Sensor
 
LDR sensor is a most popular and cheap light intensity sensor. Since the sensor's resistance varies with the amount of light falling on it, therefore this sensor is also known as the photoresistor.
 
Maximum Voltage (Vmax) 320 V
Operating Voltage (V) 3.3 V ~ 5.0 V DC
Operating Temperature (°C) -60 °C to +75 °C
Dimension of Sensor 5 mm
Range of Sensor (lx) 0.1 lx to 10000 lx
Sensitivity (lx) Dark : 1M Ω (10000 lx)
Light : 1k Ω (1000 lx)
Cost (€) 4.89 €

 
Advantages: Disadvantages:
It is low cost and easier to get this sensor. It has lower sensitivity because the resistance may vary significantly to temperature change.
It is easier to use. It is slower in response time (2 to 50ms).
It has wider range of operating temperature.  
   
   

C Sub-Function: Motion detect:
C.1 - Passive Infrared Sensor (PIR Sensor)
Figure 3.4.4 : Passive Infrared Sensor (PIR Sensor)
 
It is a sensor which can detect body heat and movement in the surroundings areas with its infrared energy. It is the most widely used motion in home security systems.
 
Input Voltage (V) 4 V ~ 12 V DC
Output Voltage (V) High level signal: 3.3 V
Low level signal: 0V
Power Consumption 65m A
Operating Temperature (°C) -20 ° C to +85 °C
Dimension 32 mm x 24 mm
Lens Size 23 mm
Detecting Range 3 - 7 m
Detecting Angle 120°
Delay time Adjustable (0.3 to 5 min)
Cost (€) 2.80 €

 
Advantages: Disadvantages:
It consume not much energy and can last longer. (0.8W to1.0W) It is insensitive to very fast or very slow motion of objects.
It has larger fields of view and suitable for enclosed place. It does not work well in certain temperatures.
It is lower cost than other sensor.  
   
   

 
C.2 - Ultrasonic Motion Sensor
Figure 3.4.5 : Ultrasonic Motion Sensor
 
It can send out pulses of ultrasonic waves and measure the reflection of a moving object.
 
Input Voltage (V) 5 V DC
Output Voltage (V) High level signal: 5 V
Low level signal: 0V
Operating Temperature (°C) -15 ° C to +70 °C
Dimension 45 mm x 20 mm x 15 mm
Detecting Range 0.02 - 4 m
Detecting Angle 15°
Speed of Detection 340 m/s
Cost (€) 3.99 €

 
Advantages: Disadvantages:
It is sensitive to minor motions. It is very expensive.
It can sense all the material types but not affected by atmospheric dust, rain and snow. Its "false alarm" rate is higher than other motion sensor.
It has higher sensing distance. Its sensitivity is vary in different temperature.
  It has difficulties in reading the reflections from soft, curved, thin and small objects.
   

 
C.3 - Microwave Sensor
 
Microwave Sensor [Source]
 
It can send out microwave pulses and measure the reflection of the moving objects. This sensor can cover a larger area than infrared sensors but it's more expensive than other motion sensors.
 
Input Voltage (V) 4.0 V - 28.0 V DC
Output Voltage (V) 3.2 V - 3.4 V
Power Consumption 20m W
Operating Temperature (°C) -20 ° C to +80 °C
Dimension 35.9 mm x 17.3 mm x 0.68 mm
Detecting Range 5 - 9 m
Detecting Angle 360°
Delay time 5 seconds to 25 minutes
Cost (€) 1.99 €

 
Advantages: Disadvantages:
It is a very sensitive sensor. It will false detect the non-metallic objects as moving object outside the target range.
It has wide coverage range. It will consume a lot of power.
   
   
   

 
D Sub-Function: User react
D.1 - Web Browser
Figure 3.4.6 : Web Browser
 
Web Browser is not only a search engine, it is also the application for user to access information on the web around the world.
 
Advantages: Disadvantages:
It will be available for both iOS user and Android user. Internet is required to open the webpage.
User do not need to download specific apps because the web page can be access in any web browser such as Google Chrome, Firefox, Internet Explorer, Opera, Microsoft Edge and so on.  
   
   
   

 
E Sub-Function: Signal receive
E.1 - ESP 32
Figure 3.4.7 : ESP 32
 
ESP32 is a microcontroller which integrated with a single 2.4 GHz Wi-Fi and Bluetooth chip. It can be programmed by using Arduino Uno IDE.
 
MCU Dual- or single- core Xtensa® 32-bit LX6 Microprocessors
Wi-Fi 802.11 b/g/n HT40
Bluetooth Bluetooth 4.2/BLE
Memory 512kB SRAM & 16MB Flash
Operating Temperature (°C) -40 ° C to +125 °C
Digital I/O-Pins 32
Cost (€) 7.99 €

 
Advantages: Disadvantages:
It is the cheapest IOT Wi-Fi and Bluetooth built-in module.  
It is much more powerful than ESP8266 which it contains more GPIOs with multiple functions, faster Wi-Fi, and also Bluetooth.  
It is easier to program, which it can use Arduino language to program it.  
   
   

 
F Sub-Function: Light switch
F.1 - AC Dimmer Module
 
AC Dimmer Module [Source]
 
AC Light Dimmer Module is a module which can be control by our microcontroller to adjust the brightness of AC light. It is designed to control the alternating current voltage, which can transfer current up to 600V / 16A. It can also be used in fans, pumps, air cleaners and so on.
 
Power 600 V - 16 A
AC Frequency 50 / 60 Hz
Load Normal: 2A ; Peak: 5A
Logic Level 3.3 V / 5 V
Signal Current > 10 mA
Operating Temperature (°C) -20 ° C to +80 °C
Cost (€) 8.08 €

 
Advantages: Disadvantages:
The system can be control automatically or manual by user through browser. It has higher cost.
The system can be control not only by on and off, but also can be adjusted for its performance by AC Light Dimmer Module. It can use Pulse Skip Modulation. However, it is not a good way to dim lights as there is a chance of flickering.
   
   
   

 
F.2 - Relay Module
Figure 3.4.8 : Relay Module
 
Relay module is a electromagnetic switch module which can control on and off of the system. It is used in the application to turn on and off a circuit with low power signal.
 
Maximum Load 250 V - 10 A
Logic Level 3.3 V
Max. ON/OFF Mechanically Switching 300 operation/min
Max. ON/OFF Electrically Switching 30 operation/min
Operating Temperature (°C) -25 ° C to +70 °C
Cost (€) 2.15  €

 
Advantages: Disadvantages:
The system can be control automatically or manual by user through browser. The system can only be control by on and off, but cannot be adjusted for its performance.
It has lower cost. Its parts can wear out as the switch contacts become dirty, as high voltage and current cause sparks between contacts.
It has wider range for Output Voltage. (up to 250 V AC) It cannot be switched on and off at high speeds because it has slow response and the switch contacts will rapidly wear out due to the sparks.
   
   

 
F.3 - Mosfet Driver Module
Figure 3.4.9 : Mosfet Driver Module
 
Mosfet driver module is a power amplifier that accepts a low power input from our microcontroller to control a high power output which is our actuator. This device can also be called as optocoupled gate driver.
 
Load 9  V to 24 V
Logic Control (Input) Low-Output : 0 V to 0.8 V
High-Output : 2.5 V to 5 V
 Temperature (°C) 40 ° C
Cost (€) 5.95  €

 
Advantages: Disadvantages:
The system can be control automatically or manual by user through browser. It has smaller range for output voltage. ( up to 24V DC)
It is necessary to keep switching time as short as possible, which it will switch at higher frequencies.
 
It is a electronic switches for controlling load. This will reduced the sparks appear between contacts.  
   
   

 
G Sub-Function: Data transmit
G.1 - Wi-Fi
Advantages: Disadvantages:
It allows long range communication between devices. Therefore, user can control their devices at anywhere of the world. If there is no internet connection, user cannot get the information .
   
   
   
   

 
G.2 - Wi-Fi & Bluetooth
Advantages: Disadvantages:
When there is no internet connection, user can also get the information by bluetooth. Bluetooth will be redundant connection if the Wi-Fi is connected.
It only allows short range communication between devices.
 
   

 
H Sub-Function: Status display
H.1 - OLED & Web Browser
Figure 3.4.10 : OLED Display
 
Advantages: Disadvantages:
User can get the informations not only from the web browser, but also from the OLED display. OLED will consume bigger space of the device.
User can get the informations without handphones, PC or tablets. Redundant information which appear in both OLED display and web browser.
   
   
   

 
H.2 - Web Browser
Advantages: Disadvantages:
User can get the informations from anywhere around the world. User cannot get the informations without handphones, PC or tablets.
This can save more space on the devices.
There will no redundant information which appear in both OLED display and web browser.  
   
   

 
I Sub-Function (Additional Home Automation Control Function): Temperature Detect
I.1 - DHT22 AM2302 Temperature and Humidity Sensor
Figure 3.4.11 : DHT22 AM2302 Temperature and Humidity Sensor
 
DHT22 is a capacitive type humidity and temperature sensor. The digital signal is fairly easy to be read by using any microcontroller such as ESP 32.
 
Operating Voltage (V) 3.3 V ~ 6 V DC
Operating Temperature (°C) -40 °C to +80 °C
Operating Humidity (%RH) 0 %RH to 100 %RH
Output Signal Digital signal via single bus
Sensing Element Polymer Capacitor
Sensitivity Humidity :  0.1%RH
Temperature : 0.1°C
Sensing Period Average 2s
Dimensions Small size : 14mm x 18mm x 5.5mm
Big size : 22mm x 28mm x 5 mm
Cost (€) 4.99 €
Advantages: Disadvantages:
It has high accuracy with humidity +-2%RH (Max +-5%RH) and temperature <+-0.5°C It has limited long term stability.
It does not need any maintenance for longer periods. It is sensitive to dewing and certain aggresice substances.
It can not only measure temperature, but also the humidity of the surrounding.  
   
   

 
I.2 - MCP 9808 I2C Temperature Sensor
Figure 3.4.12 : MCP9808 I2C Temperature Sensor
 
MCP9808 I2C temperature sensor is the one of the more accurate digital temperature sensor. It use the standard i2c to work with any microcontroller suc as ESP 32.
 
Operating Voltage (V) 2.7 V ~ 5.5 V DC
Operating Temperature (°C) -40 °C to +125 °C
Operating Current 200 μA
Sensitivity 0.0625 °C
Cost (€) 8.52€
Advantages: Disadvantages:
It has wider range of operating temperature, up to 125 °C. It only can measure the temperature.
It is more sensitive and precise compare to other temperature sensor up to 0.0625 °C. It is more expensive than other temperature sensor.
   
   
   

  With Support of Prof. J. Walter Winter Semester 2018/2019