The latest iteration of Amazon's battery-powered Ring doorbell adds a new feature to capture the early details of events most competitors would miss without needing to be plugged in. It tops Ring's battery-powered range, which starts at £89. The look and basic function of the Doorbell 4 is very similar to Ring's older models. It has a camera with night vision, motion sensors and a large doorbell button. When someone pushes the button Ring's signature chime plays and an alert is sent to your phone. You can view a live feed and speak through the doorbell using the app from anywhere with internet.

This paper investigates an unmanned aerial vehicle (UAV)-assisted wireless powered mobile-edge computing (MEC) system, where the UAV powers the mobile terminals by wireless power transfer (WPT) and provides computation service for them. We aim to maximize the computation rate of terminals while ensuring fairness among them. Considering the random trajectories of mobile terminals, we propose a soft actor-critic (SAC)-based UAV trajectory planning and resource allocation (SAC-TR) algorithm, which combines off-policy and maximum entropy reinforcement learning to promote the convergence of the algorithm. We design the reward as a heterogeneous function of computation rate, fairness, and reaching of destination. Simulation results show that SAC-TR can quickly adapt to varying network environments and outperform representative benchmarks in a variety of situations.

For years, SimpliSafe's only option for outdoor video monitoring (other than the Video Doorbell Pro) was its indoor-only SimpliCam wrapped in a weatherproof rubber sleeve. Now, the company is finally offering a proper, battery-powered outdoor cam, complete with a weatherized shell, a spotlight, and people detection. Available now for $170, the SimpliSafe Wireless Outdoor Security Camera is a svelte, cylindrical camera with a swiveling magnetic base, Wi-Fi connectivity, Alexa and Google Assistant support, and a rechargeable, replaceable battery that promises to deliver between 3 and 6 months of battery life on a single charge. Equipped with two antennas, the new SimpliFi outdoor cam is capable of connecting to 2.4GHz Wi-Fi networks, but it won't work without a SimpliSafe base station. To get a base station, you'll need to purchase one of SimpliSafe's alarm systems, which start at $230 for a four-piece kit.

With this completely new and battery-powered iteration of the Nest Cam, Google's smart home division continues to raise the bar when it comes to security cameras, setting a standard for usability (especially during setup) that most other device manufacturers can only dream of. From a hardware perspective, the Nest Cam is a radical refresh of the old teardrop-shaped Nest Cam Indoor, designed with a tough, plastic, cup-shaped housing that adheres magnetically to its surface-mountable base (it looks very similar to the now-discontinued Nest Cam IQ). It's reasonably weather resistant, carrying an IP54 rating (meaning its enclosure will keep out enough dust to prevent failure and that it's protected from water sprayed from a pressure washer at a reasonable distance), so it can be used indoors or outdoors. The 2021 version of the Nest Cam carries an IP rating of 54, meaning its enclosure will keep out enough dust to prevent failure and that it's protected from water sprayed from a pressure washer at a reasonable distance. The new Nest Cam can run on battery power, and Google says it should deliver between 1.5 and seven months of run time before it needs to be recharged, depending on usage.

It's been three years since Google launched the Nest Hello, a wired video doorbell with facial recognition that helped set the standard for smart doorbells. In that time, many competitors have appeared, but few have come close to the quality and reliability of that device. The Nest Doorbell (battery) is a Google-made video doorbell that can run on battery power (it can also operate on wired power, if you have that infrastructure and wish to connect it to your existing doorbell chime). In our tests the device performed excellently, didn't give any problems, and proved itself to be a worthy sister device to the original Nest Hello. A large, round black circle with a camera in its center is at the top of the new Nest doorbell. A small LED below that indicates when the camera is recording or processing video.

Eufy's SoloCam E40 eliminates a couple of pain points common to many home security cameras. Powered by a rechargeable battery, the E40 offers a wire-free installation that removes such logistical challenges as finding a convenient electrical outlet or installing entirely new electrical wiring that can make outdoor installations vexing. Secondly, it includes 8GB of onboard storage that stores about a month worth of video recordings, so you don't need to buy a cloud subscription to get the maximum security benefit from the camera. The E40 has a rectangular body similar to the EufyCam 2, enabling it to stand freely on any flat surface. It comes with a compact wall mount that screws into the back of the camera and can be affixed to a wall with the accompanying hardware.

Within electrical distribution networks, substation constraints management requires that aggregated power demand from residential users is kept within suitable bounds. Efficiency of substation constraints management can be measured as the reduction of constraints violations w.r.t. unmanaged demand. Home batteries hold the promise of enabling efficient and user-oblivious substation constraints management. Centralized control of home batteries would achieve optimal efficiency. However, it is hardly acceptable by users, since service providers (e.g., utilities or aggregators) would directly control batteries at user premises. Unfortunately, devising efficient hierarchical control strategies, thus overcoming the above problem, is far from easy. We present a novel two-layer control strategy for home batteries that avoids direct control of home devices by the service provider and at the same time yields near-optimal substation constraints management efficiency. Our simulation results on field data from 62 households in Denmark show that the substation constraints management efficiency achieved with our approach is at least 82% of the one obtained with a theoretical optimal centralized strategy.

Google is refreshing its Nest lineup with three new products and a refresh for the wired indoor Nest Cam. Among the newcomers are Google's first battery-powered Nest Cam and Doorbell, as a recent leak indicated. You'll be able to install them just about anywhere around your home, and connect them to a wired power source, if you prefer. The battery life depends on how many recorded events the devices detect and factors like the temperature and settings. Google says the Doorbell's battery will run for up to six months on a single charge, while the Nest Cam can run for up to seven months before you need to juice it up.

In recent years, the use of lithium-ion batteries has greatly expanded into products from many industrial sectors, e.g. cars, power tools or medical devices. An early prediction and robust understanding of battery faults could therefore greatly increase product quality in those fields. While current approaches for data-driven fault prediction provide good results on the exact processes they were trained on, they often lack the ability to flexibly adapt to changes, e.g. in operational or environmental parameters. Continual learning promises such flexibility, allowing for an automatic adaption of previously learnt knowledge to new tasks. Therefore, this article discusses different continual learning approaches from the group of regularization strategies, which are implemented, evaluated and compared based on a real battery wear dataset. Online elastic weight consolidation delivers the best results, but, as with all examined approaches, its performance appears to be strongly dependent on task characteristics and task sequence.

Researchers have figured out a way to rapidly recharge ultra dense batteries capable of powering flying cars, theoretically making them suitable for everyday use. The breakthrough with electric vertical take-off and landing (eVTOL) vehicles could enable the commercialisation of next-generation transport systems in the near future, according to the researchers from Penn State university who made the discovery. "I hope that the work we have done in this paper will give people a solid idea that we don't need another 20 years to finally get these vehicles," said Chao-Yang Wang, director of the Electrochemical Engine Center, Penn State. "I believe we have demonstrated that the eVTOL is commercially viable." The research was published today, 7 June, in the scientific journal Joule.