How Does the Motion Detection Feature of Video Locks Safeguard Your Home?
In the realm of smart locks, motion detection plays a vital role in ensuring home security. When a stranger lingers or loiters at the doorstep, the smart lock's motion detection feature is triggered. The lock's camera captures snapshots of the individual and sends them to the user's mobile device, providing round-the-clock protection for the household.
Currently, the mainstream technologies for human motion detection in the smart lock market include PIR (Passive Infrared), Doppler Microwave Sensing, and PCR (Phase Coherent Radar) sensing. Let’s delve into each of these technologies in detail.
Infrared sensing (PIR)
Infrared sensing (PIR) operates based on the principle of pyroelectric infrared detection, triggering the sensor by capturing changes in infrared energy. Human body temperature typically ranges between 36-37°C, emitting infrared radiation at a specific wavelength of approximately 10 μm. When a person passes by, the specific infrared radiation emitted by their body triggers the pyroelectric element, generating an alarm signal. PIR sensors have low power consumption and are cost-effective, making them a popular choice for many smart lock manufacturers. However, the signal amplitude of PIR technology is easily affected by various heat and light sources.
Doppler Microwave Sensing Technology
Doppler microwave sensing, commonly referred to as electromagnetic radar sensing, uses the Doppler effect to detect the position and relative motion speed of moving targets. When a moving object enters the sensing range, the sensor detects changes in the radar signal waveform, triggering the microwave sensor to generate an alarm signal.
Compared to infrared sensing technology, Doppler microwave sensing is unaffected by temperature, humidity, or brightness. Additionally, it can penetrate plastic, allowing for concealed installation, which enhances its aesthetic appeal. However, Doppler microwave sensing can only detect moving individuals and is ineffective for stationary or sleeping individuals. Currently, the application of Doppler microwave sensing technology in the smart lock market is limited, with key adopters including the Yingdeman brand under Sanmu Smart.
PCR Radar Sensing Technology
PCR radar sensing technology operates on the principle of using ultra-wideband to perform high-precision micro-movement detection, allowing it to detect human breathing signals, which then trigger the sensor to generate an alarm signal.
PCR radar sensing technology has strong anti-interference capabilities and is not affected by environmental factors such as temperature, humidity, or smoke. It offers high recognition accuracy and can be powered by batteries, making it widely used in smart wearables, smart homes, IoT, and other scenarios. Since PCR radar can penetrate plastic, the sensor can be installed discreetly, making it more aesthetically pleasing.
RCR radar sensing technology is the most advanced generation of human sensing detection technology available today.
From the above analysis, it can be seen that the mainstream human movement detection technologies in the smart lock market each have their own advantages and disadvantages. PIR technology is widely used in smart door locks due to its low power consumption and low cost. Doppler microwave sensing technology is less commonly used. PCR radar sensing technology, which is the most advanced human sensing technology, is rarely used due to its technical complexity.
As video locks and networked locks become a trend in the market, movement detection technology is increasingly being applied by manufacturers to smart door lock products to provide users with better home security services. Some industry professionals even say: "A product with video intercom functionality, like a video lock, feels incomplete without movement detection, compromising its safety protection." This reflects the importance of movement detection and the market's preference for this feature.
However, on the other hand, for video lock products with movement detection functionality, power consumption can be a significant challenge. Although the technologies used generally have low power consumption, once movement detection triggers an alarm, the smart peephole module is activated, which increases the overall power consumption. For most products, users can personalize the activation or deactivation of this feature based on their needs, but this doesn't fundamentally solve the power consumption issue unless the battery capacity is increased, like in the new Ezviz DL31FVS smart facial recognition video lock, which is equipped with a 20,000mAh lithium battery. However, such locks are rare in the market.
Regardless, the presence of movement detection functionality fundamentally increases the security performance of video locks. Through the technical principles shared in this article, we hope to clarify the current state of technology development in smart locks and gain insight into their future trends. It also prompts a consideration: How can smart locks safeguard users' home security in a more secure and efficient way, and can high security and low power consumption coexist?