MapsHalli

Category: IOT

  • Why you should not take morning or evening walks?

    Why you should not take morning or evening walks?

    Updated: Oct-01-2018

    Executive Summary

    Do you know someone who lives in the Whitefield area who goes for morning or evening walks? Why are we recommending that you should not take morning or evening walks? What is the best time to walk then?

    Based on the air quality analysis based on the data from March-01-2018 to Sep-30-2018, from Purple Air sensor located at Thubarahalli we found the following:

    • Air quality is the worst between 06:00AM – 08:00AM and between 07:00PM – 08:00PM.
    • Air quality is worse during the months of March and April; it becomes better during June and July.
    • Saturday has the worst air quality and Monday is the best day.
    • 13th of every month has the best air quality and 31st  has the worst air quality.

    Are you concerned about air quality and pollution? Want to know how to plan your day so that you are exposed to least amount of pollution? Please continue reading… The following topics are covered in detail:

    1. What is PM2.5 and how does it relate to pollution?
    2. Where to view PM2.5 data for Whitefield, Bangalore?
    3. Data analysis of air pollution from March-01-2018 to Sep-30-2018 and findings.
    4. How does pollution change month by month?
    5. What are the best and worst air quality days in a month?
    6. Which day of the week is the most polluted?
    7. Which hours of the day is the most and least polluted?

    What is PM2.5 and how does it relate to pollution?

    The term PM2.5 refers to fine particles or droplets of size 2.5 microns are less. This is 30 times smaller than an human hair. These particles are so small that they can reach your blood stream through the lungs. These particles come from vehicle exhausts, , vehicle brakes, construction, road dust, and fuel burning. Long term exposure to these particles cause increase rates of chronic bronchitis, reduced lung function, lung cancer, kidney disease, and diabetes.

    PM2.5 is measured in µg/m3  (micro grams in a cubic meter).

    PM2.5 Standards

    WHO PM2.5 standards

    WHO recommended guidelines is 10µg/m3  for annual average and 25 µg/m3 for 24 hour average. There is no safe level of PM2.5.

    USA PM2.5 standards

    The USA standard for PM2.5 (µg/m3  24 hours), category, and health impacts are shown below.

    •  0 to 12.0 – Good
      • Air quality is considered satisfactory, and air pollution poses little or no risk.
    • 12.1 to 35.4 – Moderate
      • Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.
    • 35.5  to 55.4 – Unhealthy for Sensitive People
      • Members of sensitive groups may experience health effects. The general public is not likely to be affected.
    • 55.5 to 150.4 – Unhealthy
      • Everyone may begin to experience some adverse health effects, and members of the sensitive groups may experience more serious effects.
    • 150.5 to 250.4 – Very Unhealthy
      • Health alert: everyone may experience more serious health effects.
    • 250.5 to 500.4  – Hazardous
      • Health warnings of emergency conditions. The entire population is more likely to be affected.

    Where to view current values of PM2.5 in Whitefield, Bangalore?

    You can view the latest value (PM2.5 short term) and 24 hour average values at:

    https://aircare.mapshalli.org

    AirCare operates community based high density air quality network for Whitefield. Currently, there are 12 such sensors in operation.

    You can also view data from one government sensor at:

    http://aqicn.org/city/india/bangalore/bwssb/

    Data analysis of air pollution from March-01-2018 to Sep-30-2018 and key findings

    Mr. Rahul Bedi has been operating an air quality and weather station at Pride Orchid, Whitefield.  The sensor data is available at purpleair.

    We have analyzed over  222,216 sensor readings and found the following:

    • Air quality is the worst between 06:00AM – 08:00AM and between 07:00PM – 08:00PM.
    • Air quality is worse during the months of March, April, and Sep; it is better during June and July.
    • Saturday has the worst air quality and Monday is the best day.
    • 13th of every month has the best air quality and 31st of the month has the worst air quality.

    How does pollution change  month by month?

    Although the air quality is becoming better over the months, it is expected to become worse after the monsoon is over and during the Diwali season.

    What are the best and worst air quality days in a month?

    After all, 13th is not an unlucky day, it is the least polluted day  in a month. Don’t step out of the house on the 31st.

    How does pollution change by the day of the week?

    How does pollution change by the hour of a day?

    The best time to walk is during the lunch hour!  Avoid those early morning walks!

    Conclusion

    Hope the above data analysis can help to plan your days and hours better and avoid air pollution. You can contribute by becoming a host of a community air quality sensor. Read more about it here.

  • Methods to configure an IoT device for the first time

    Methods to configure an IoT device for the first time

    Introduction

    In this article, I will discuss the challenges in setting up an IoT device for the very first time and suitable methods to address these challenges.

    Many IoT devices are now being shipped to end consumers and these consumers are expected to setup the devices. For example, the product AirCare IoT is a Raspberry PI based air quality sensor that needs to be setup by a consumer for the first time.

    Although AirCare IoT has a built-in ethernet port, we expect the unit to be installed in a garage or a balcony where an ethernet cable is not expected to be available. The only other option is to use the Wi-Fi network.  Also, no display monitor with keyboard can be  connected to the IoT to allow easy configuration. Consumers expect a device such as this be easily setup using an phone app.

    Expected Procedure for Configuration

    A consumer would expect the following logical steps to configure the device:

    1. If not done already, download the app from the app store.
    2. Turn on the power for the device.
    3. Launch the app in the phone, the device should auto recognized, perform an easy setup.

    Challenges

    Factory shipped IoT can’t connect to Wi-Fi network at home

    In order for the above procedure to work, the IoT device should be connected to a Wi-Fi network is generally accessible from the app.  This is not possible, as the IoT shipped from the factory does not know your home Wi-Fi network name and the password! The first step in the setup should logically involve providing the home Wi-Fi network and the password.

    The IoT can be shipped to host an hot-spot with a known name (SSID), for example, AirCare Config, and a known password. The user can be instructed to connect  their phone to this Wi-Fi network temporarily to complete the setup. The user after a successful setup can connect the phone to their regular home Wi-Fi network.

    Once the network settings are available, the IoT can join the home Wi-Fi network.  The IoT can fall back to be an hot-spot if the credentials are invalid or has other connectivity issues.

    Can’t find the IP address of the just setup IoT

    Now we face a new challenge! Once the IoT connects to the home Wi-Fi network we need to know its IP address to connect to it from the app. This process would involve accessing the Wi-Fi router admin page and inferring the IP address. We can’t expect a consumer to perform this action!

    Conversely, the IoT can’t connect to the app because it does not know the IP address of the phone or the phone IP address could have changed. Also, the incoming network connections to apps are also discouraged in practice. The app would have learnt the MAC address of the IoT and can do use RARP (Reverse Address Resolution Protocol)  to map MAC address to the IP address. This level of deep networking stack access is not available to the apps.

    Furthermore, there is no central server like system at home that can share such information.

    Solution: Use an publicly hosted custom registry that can map MAC address to the IP Address

    In this solution, the IoT upon joining the home Wi-Fi network registers itself to a registry server using a well defined REST API as following:

    POST http://aircare-registry.mapshalli.org/register

    Parameters:

    • MAC address
    • IP address

    Now, the android app can query to get the IP address as follows:

    GET http://aircare-registry.mapshalli.org/register/<mac_address>

    Returns:

    Access credentials and other parameters have been omitted for brevity. The IP address of the IoT itself is not a publicly visible IP address but private address that is only valid in the local Wi-Fi network. The session mapping of public IP address to the private address is done automatically by the local router(s) using the NAT protocol.

    The app needs to manage its own MAC address to IP address table and use TTL values to intelligently query to get the IP address.

    Further Study

    The challenges and solutions points to the glaring gap of lack of centralized IoT management at home.