The Smarter Side of Mobile: Data Collection through Wireless Sensor Networks
Mobile devices are at the center of our everyday lives. Society has increasingly grown dependent up these devices. We rely on our phones or tablets to schedule our activities, conduct research, make purchases, and stay connected with our digital network. Mobile technology is becoming more intuitive, adapting to a multitude of our daily needs. There is another dimension of mobile that most of us are unaware of. Mobile devices around the world are being used to solve important and complex environmental issues. How is this possible? Thanks to sensor technology and companies developing platforms to utilize the power of mobile measurement.
Exploring Sensor Technology
Sensors play an important role in providing feedback about a particular environment. They measure a given quantity and convert the measurement into a signal for analysis. (http://en.wikipedia.org/wiki/Sensor, December 2012) The role of sensors is widespread and is used to monitor a variety of systems ranging from radioactivity levels in nuclear power plants, to your daily fitness stats courtesy of the Nike Fuel Band. Combining sensors into networks gives way to powerful measurement potential. The development of Wireless Sensor Networks (WSNs) has provided the foundation to measure real world systems with greater accuracy and scope in collection.
Environmental Wireless Networks
WSNs are used in an array of applications including: Area, Environmental/Earth, Industrial, Agriculture, Structural, Passive localization and tracking, and Smart Home monitoring. WSNs used in earth science, called Environmental Wireless Networks, are used to measure multiple factors ranging from air quality to natural disaster prevention. These sensors have the ability to collect information about the environment in real time including reporting on factors such as temperature, humidity, rainfall, wind speed, atmospheric pressure, UV levels, and air pollutant levels. (http://en.wikipedia.org/wiki/Wireless_sensor_network#Environmental.2FEarth_monitoring, December 2012) Despite providing accurate results, using sensor technology for data collection can be quite expensive due to companies relying on customized hardware/software in sensor development and collection. How can WSNs still be utilized at a lower cost? This is an important issue Los Angeles based non-profit Nexleaf Analytics has resolved: utilizing mobile technology to connect to sensors, store and report data. (“Turning The World’s Cell Phones Into A Network Of Sensors.” http://www.fastcoexist.com December 2012).
Nexleaf Analytics is a non-profit organization founded by Dr. Nithya Ramanathan and Dr. Martin Lukac. Utilizing their experience in mobile platform development wireless sensor network technology, Ramanathan and Lukac have leveraged the convenient use of mobile to monitor, analyze, and report pertinent findings in relation to important issues regarding the environment, climate change, and public health. Below is a more detailed description of how mobile measurement is used in a few of Nexleaf Analytics’ projects.
Project Surya is a climate change focused project. Core goals include assessing impacts of global warming on a regional basis throughout India. According to Ramanthan, approximately three billion people use open flames for cooking. This contributes to two million deaths each year and impacts climate change based upon toxic emissions from the soot released into the air. Project Surya is hoping to reverse these effects by encouraging the shift towards using more efficient stove technologies. Nexleaf Analytics has developed an efficient measurement system to produce data in support of this initiative. A basic mobile flip phone is connected to a sensor via the headset jack. The sensor then measures the air quality of the cook stove being used both indoors and outdoors. After a day of cooking, the filters in the sensor are removed and photographed on a provided chart using the mobile phone. The image is then sent by MMS to Nexleaf’s servers. Data collection becomes automatic, specific algorithms translating the color of the filter into a set concentration of soot in the air. A simple flip phone being distributed in villages across India empowers those directly impacted by the issue to affect change with in their environment. Concrete data is now available to impact policy and to show the benefits of using cook stoves to improve a public health and climate issue.
Another key project for Nexleaf Analytics is exploring how exposure to excessive noise pollution impacts a person’s health. Many of us may not consider noise from our environment as affecting our state of health, however according to Nexleaf’s program description; ‘noise can be linked to stress-related conditions including hypertension, heart disease, stroke, and heart attack.’ Nexleaf has developed a mobile phone tool called SoundProof to measure the impact of noise in a person’s daily environment. Mobile phones with audio recording capabilities will record noise levels a person encounters throughout the day. The use of GPS will give greater context to the data by providing location information. Researches can use the information collected through SoundProof to formulate conclusions at a granular level by having access to time, location, noise levels, and activity based metrics extracted from a mobile platform.
Having reached out to Nexleaf Analyics to learn more about their work, I was honored by the opportunity to ask Nexleaf’s Chief Operating Officer Dr. Ian Leong a series of questions regarding mobile measurement.
1. Are mobile devices the untapped tool for measurement? Please explain how.
In terms of data collection, mobile phones have been a very exciting space for the past several years. In our work, we started looking at how we could leverage existing technologies instead of building new ones from the ground up, which is typically very expensive and often inefficient. Cellphones use a widespread infrastructure that already exists and is very robust, even in developing areas.
However, the viability of using that infrastructure is often dependent on the kind of mobile devices that are available in a particular area. While it is possible to develop expensive sensors connected to very sophisticated devices such as an iPhone, those devices are not very prevalent in developing regions.
So one of the early challenges that we faced was whether we could use sensor-enabled cellphones to collect and analyze data and whether it could be done cheaply. We wanted sensors that would work with a $25 phone that you can purchase in a village in India so that the system would be widely compatible and so we could collect data from almost anywhere.
As wireless networks spread and as more sophisticated devices fall in price and become more readily available to greater numbers of people, we expect that these kinds of mobile sensing will expand and that the functionality of mobile data collecting devices will grow in complexity and usability.
2. You use mobile to measure environmental factors. What other measurement capabilities does mobile offer? Are there limits on measurement?
Mobile phones have the ability to monitor many activities, behavior and sources of data, including (without limiting the scope) those pertaining to health factors, animal behavior, and the capabilities of other instruments. It’s probably a little early to delineate hard limits on mobile data collection as the field is still relatively new and the technology on which it is based continues to develop at a very rapid pace. However, certain general factors which will likely shape the way that mobile collection occurs include the overall energy efficiency of the devices, battery life, cost of the devices as well as the cost of wireless services, bandwidth availability, data privacy issues, and the openness of mobile system platforms to allow for applications to be built on top of them.
3. How do you envision mobile data collection impacting traditional industry standards of data collection methods?
This may be dependent on the type of data that you are collecting. The standards that we generally deal with at Nexleaf are based on well-established scientific processes. So those processes and associated methods of proof will likely be slow to change in terms of existing questions and research to which the data is being applied. However, as data becomes available from a greater number of sources, new kinds of questions and new research areas may well open up. So as the amount of data that becomes available grows and becomes easier and cheaper to come by, that volume and that availability could cause people to begin looking to research topics that were ignored or discarded because they were previously logistically impossible or too expensive to consider.
4. Describe the pros and cons of mobile data collection. What steps are taken to ensure accuracy with the data?
The benefits of mobile data collection include the fact that you can obtain data at a much more granular and detailed scale, from many more people, and in many more locations. Since the collection process relies on an existing infrastructure and mobile devices that are very common, the cost of collecting data can be driven down. That lowered cost helps increase the granularity of the collected data because it can make the deployment of more sensors affordable.
The potential drawbacks include the fact that the ability to transmit the collected data can be dependent on the quality of the mobile device’s wireless connection (if you are not planning to retrieve the device frequently). Moreover, if casual users of cellphones collect the data (as opposed to professional researchers), then you may have greater variability in the quality of the data because of collection inaccuracies. In our experience, these drawbacks often can be mitigated or overcome by planning for potential wireless outages and developing strong “work-arounds,” providing good training materials and procedures for users to follow, simplifying the process of data input, automating the collection where possible, and shifting the calculation and analysis off of the mobile device to the server-side of the collection process.
5. Does mobile measurement have the potential to cross over to other markets, specifically to measure and monitor consumer behavior? Are platforms being developed for this?
Monitoring consumer behavior isn’t exactly our field of work. So we can’t comment too much about this issue and ongoing trends. But we imagine that, as mobile devices become much more a key part of the purchasing process through mobile payment systems such as Google Wallet or text message money transfers, these transactions will be sources of data for tracking consumer behavior.
6. How can interested parties become involved with and contribute towards the success of Nexleaf’s projects?
Anyone who is interested in our work can visit our website, www.nexleaf.org, for more information and can follow us on Twitter, at @Nexleaf. They are also welcome to contact us at firstname.lastname@example.org.
As mobile technology evolves, greater opportunities are available in providing solutions to pertinent social and environmental issues. Nexleaf Analytics has developed an innovative method of measurement that yields powerful data. Utilizing sensor technology that already exists in mobile devices in addition to connecting devices to WSNs creates a promising outlook for data collection and analysis of real world systems. Continued work in the development of mobile measure technology is significant. These methods revolutionize the use of simple objects to provide solutions that promote change and improve everyday life.
For more information on Nexleaf Analytics’ work visit www.nexleaf.org, follow on Twitter @Nexleaf, and check out a video interview with Dr. Nithya Ramanathan about Project Surya (http://www.fastcoexist.com/1680766/turning-the-worlds-cell-phones-into-a-network-of-sensors).