With the Dual Tech/Hybrid, both sensors will need to sense changes which will trigger it on, causing false alarms to be extremely low. A quick rise in temperature in the room can cause the PIR to go off while wind can move an object and trigger the microwave sensor. There is technology that incorporates both PIR and Microwave sensors to have less false alarms. Dual Tech Motion Sensors: How Dual Tech/Hybrid Sensors Work Its ability to penetrate material “see through walls” can cause frequent false alarms. Microwave sensors can cover a larger area than PIRs, but are more expensive and can be vulnerable to electrical interference. Figure 3 shows how the Microwave sensors work.įigure 3: Frequency shift on an object causes the signal to be amplified, detecting motion. If it does detect a frequency shift, the motion detector is activated. It sends out high radio frequency and measures the reflection off an object by sensing for a frequency shift.
View Microwave Motion Sensors: How Microwave Sensors WorkĪs the name implies, Microwave sensors uses continuous waves of microwave radiation to detect motion, similar to how a radar speed gun works. (Source: Adafruit/Lady Ada) See related product Figure 2 shows the inside of the Fresnel lens, where you can see the “sections” on it.įigure 2: Inside a Fresnel lens. The optic physics behind the Fresnel lens is a whole other interesting area to look into if you have time, but in this case, it gives the PIR sensor a much larger detection area making it more efficient. The white plastic that you see on the PIR is called a Fresnel lens. Figure 1 from Adafruit shows a great example of how it works.įigure 1: PIR sensing heat source movement and outputting pulses. When the sensor senses a differential change between the two slots, this causes a pulse, which is what it detects as “movement”. The PIR has two slots made of a special material that is sensitive to infrared. PIRs have a pyroelectric sensor that detects levels of infrared radiation – everything emits some low-level radiation, but a human body emits a good amount of heat.
The way it senses movement is by sensing the change in temperature between the background and a warm body. They are small, low power, easy to use, and inexpensive. The PIR is a motion sensor that you might have seen when you enter a restroom or an office space, usually having a white cover. Passive Infrared Sensors: What is a PIR Sensor? There are three types of motion sensors that are used frequently: Passive Infrared (PIR), Microwave, and Dual Tech/Hybrid. It can be an energy saver by shutting off lights in a building when it senses no motion anymore, which is used regularly in office buildings or restrooms. They can be used for burglary alarms or security cameras, activating these devices when it senses motion in the vicinity. Technical specifications of the sensor are described in its User's guide.Motion sensors are popular when it comes to security and energy efficiency. The Motion detector can be directly connected to the digital BT inputs of the CMA interfaces (CoachLab II/II+ and VinciLab).įor CLAB and WiLab you can use Motion detector BT55i.
#Motion detector free#
Acceleration due to gravity - free fall, objects dropped or tossed upward.Simple harmonic motion, such as a weight hanging on a spring.Walking toward and away from the sensor.
The Motion sensor can be used for studying a variety of motions including: The rod can be used for clamping into a suitable holding device, e.g. The sensor is supplied with a steel rod, which can be screwed into a mounting thread.
These threads can be used to mount the detector to a stand and they are compatible with typical tripod mounting hardware. The motion detector has mounting threads on the bottom and both sides of the unit. For smaller objects or objects that are not very flat, the maximum detection distance will be smaller. a wall) that is perpendicular to the detector. Note that the maximum detection distance of 12 m can only be reached under ideal conditions, i.e. The maximum range is 6 to 12 m, depending on the size, shape, orientation and surface of the object that is detected. The minimum range of the motion detector is 0.20 meters. While the Motion detector is operating, a slight clicking sound from the sensor will be heard. The sensor measures the time it takes an ultrasonic pulse to travel from the sensor to the object and determines the distance from the object based on the measured time and the speed of sound. The Motion detector 0664 is a sonar device that emits ultrasonic pulses, which reflect off an object.
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