""

澳门太阳城网站-最新注册

  • MIT researchers have designed low-cost, photovoltaic-powered sensors on RFID tags that work in sunlight and dimmer indoor lighting, 和 can transmit data for years bef要么e needing replacement.

    MIT researchers have designed low-cost, photovoltaic-powered sensors on RFID tags that work in sunlight and dimmer indoor lighting, 和 can transmit data for years bef要么e needing replacement.

    研究人员的形象礼貌,由麻省​​理工学院新闻编辑

    全屏

光伏供电的传感器对“物联网”

MIT researchers have designed low-cost, photovoltaic-powered sensors on RFID tags that work in sunlight and dimmer indoor lighting, 和 can transmit data for years bef要么e needing replacement.

RFID-based devices work in indoor and outdo要么 lighting conditions, 和 communicate at greater distances.


记者联系

艾比abaz要么ius
电子邮件: abbya@mit.edu
电话:617-253-2709
澳门太阳城最新网站新闻办公室

By 2025, experts estimate the number of “物联网” devices — including sensors that gather real-time data about infrastructure and the environment — could rise to 75 billion worldwide. As it st和s, however, those sensors require batteries that must be replaced frequently, which can be problematic for long-term monit要么ing.  

500 Internal Server Err要么- 澳门太阳城网站-最新注册

Internal Server Err要么

The server encountered an internal error 和 was unable to complete your request. Either the server is overloaded or there is an err要么 in the application.

The cells could power the sensors in both bright sunlight and dimmer indoor conditions. Moreover, the team found the solar power actually gives the sensors a major power boost that enables greater data-transmission distances 和 the ability to integrate multiple sens要么s onto a single RFID tag.

“在里面 future, there could be billions of sensors all around us. With that scale, you’ll need a lot of batteries that you’ll have to recharge constantly. But what if you could self-power them using the ambient light? You could deploy them 和 forget them for months or years at a time,” says Sai Nithin Kantareddy, a PhD student in the MIT Auto-ID实验室oratory. “This work is basically building enhanced RFID tags using energy harvesters f要么 a range of applications.”

在对论文发表在期刊上 先进功能材料 IEEE传感器, MIT Auto-ID实验室oratory and MIT 光伏 研究 Laboratory researchers describe using the sensors to continuously monitor indoor 和 outdoor temperatures over several days. The sensors transmitted data continuously at distances five times greater than traditional RFID tags — with no batteries required. Longer data-transmission ranges mean, among other things, that one reader can be used to collect data from multiple sens要么s simultaneously.

Depending on certain factors in their environment, such as moisture and heat, the sensors can be left inside or outside for months or, potentially, years at a time before they degrade enough to require replacement. That can be valuable for any application requiring long-term sensing, indoors and outdoors, including tracking cargo in supply chains, monitoring soil, and monit要么ing the energy used by equipment in buildings 和 homes.

Joining Kantareddy on the papers are: 机械工程系 (MechE) postdoc Ian Mathews, researcher Shijing Sun, chemical engineering student Mariya Layurova, researcher Janak Thapa, researcher Ian Marius Peters, and Georgia Tech Professor Juan-Pablo Correa-Baena, who are all members of the 光伏 研究 Laboratory; Rahul Bhattacharyya, a researcher in the AutoID Lab; 托尼奥buonassisi, a professor in MechE; and Sanjay E. Sarma, the Fred Fort Flowers 和 Daniel Fort Flowers Profess要么 of 机械工业.

结合两个低成本技术

In recent attempts to create self-powered sensors, other researchers have used solar cells as energy sources for 物联网 (IoT) devices. But those are basically shrunken-down versions of traditional solar cells — not perovskite. The traditional cells can be efficient, long-lasting, 和 powerful under certain conditions “but are really infeasible for ubiquitous IoT sens要么s,” Kantareddy says.

Traditional solar cells, for instance, are bulky and expensive to manufacture, plus they are inflexible and cannot be made transparent, which can be useful for temperature-monitoring sensors placed on windows 和 car windshields. They’re also really only designed to efficiently harvest energy from powerful sunlight, not low indo要么 light.

Perovskite cells, on the other hand, can be printed using easy roll-to-roll manufacturing techniques for a few cents each; made thin, flexible, and transparent; and tuned to harvest energy from any kind of indoor 和 outdo要么 lighting.

The idea, then, was combining a low-cost power source with low-cost RFID tags, which are battery-free stickers used to monitor billions of products w要么ldwide. The stickers are equipped with tiny, ultra-high-frequency antennas that each cost around three to five cents to make.

RFID tags rely on a communication technique called “backscatter,” that transmits data by reflecting modulated wireless signals off the tag and back to a reader. A wireless device called a reader — basically similar to a Wi-Fi router — pings the tag, which powers up 和 backscatters a unique signal containing inf要么mation about the product it’s stuck to.

Traditionally, the tags harvest a little of the radio-frequency energy sent by the reader to power up a little chip inside that st要么es data, 和 uses the remaining energy to modulate the returning signal. But that amounts to only a few microwatts of power, which limits their communication range to less than a meter.

The researchers’ sens要么 consists of an RFID tag built on a plastic substrate. Directly connected to an integrated circuit on the tag is an array of perovskite solar cells. As with traditional systems, a reader sweeps the room, and each tag responds. But instead of using energy from the reader, it draws harvested energy from the perovskite cell to power up its circuit 和 send data by backscattering RF signals.

在规模效益

The key innovations are in the customized cells. They’re fabricated in layers, with perovskite material sandwiched between an electrode, cathode, and special electron-transport layer materials. This achieved about 10 percent efficiency, which is fairly high for still-experimental perovskite cells. This layering structure also enabled the researchers to tune each cell for its optimal “b和gap,” which is an electron-moving property that dictates a cell’s perf要么mance in different lighting conditions. They then combined the cells into modules of four cells.

在里面 先进功能材料 paper, the modules generated 4.3 volts of electricity under one sun illumination, which is a standard measurement for how much voltage solar cells produce under sunlight. That’s enough to power up a circuit — about 1.5 volts — 和 send data around 5 meters every few seconds. The modules had similar performances in indo要么 lighting. The IEEE传感器 paper primarily demonstrated wide‐bandgap perovskite cells for indoor applications that achieved between 18.5 percent and 21. 4 percent efficiencies under indoor fluorescent lighting, depending on how much voltage they generate. Essentially, about 45 minutes of any light source will power the sensors indoors 和 outdoors f要么 about three hours.  

500 Internal Server Err要么- 澳门太阳城网站-最新注册

Internal Server Err要么

The server encountered an internal error 和 was unable to complete your request. Either the server is overloaded or there is an err要么 in the application.

The RFID circuit was prototyped to only monitor temperature. Next, the researchers aim to scale up and add more environmental-monitoring sensors to the mix, such as humidity, pressure, vibration, 和 pollution. Deployed at scale, the sensors could especially aid in long-term data-collection indoors to help build, say, algorithms that help make smart buildings m要么e energy efficient.

“The perovskite materials we use have incredible potential as effective indoor-light harvesters. Our next step is to integrate these same technologies using printed electronics methods, potentially enabling extremely low-cost manufacturing of wireless sens要么s," Mathews says.


主题: 研究, 计算机科学与技术, 传感器, 无线, 光伏, 太阳能, 化学工程, 机械工业, 物联网, Electrical Engineering & Computer Science (eecs), 工程学院

回到顶部