![1] Piezoelectric
• Piezoelectric acceleration sensors measure acceleration, vibration,
and shock by converting mechanical energy into electrical signals.
• They rely on the piezoelectric effect, which is the ability of certain
materials to generate an electric charge when subjected to
mechanical stress.
• The sensor consists of a piezoelectric crystal sandwiched between
two electrodes.
• When the sensor is subjected to acceleration, the crystal deforms,
generating an electric charge that is proportional to the magnitude
of the acceleration.
• Piezoelectric acceleration sensors are widely used in various
industries, such as aerospace, automotive, and industrial
applications, due to their high sensitivity, low noise, and wide
frequency range.
5](https://image.slidesharecdn.com/accelerationandvelocitysensor-230409214018-faf52dc6/85/acceleration-and-velocity-sensor-pptx-5-320.jpg)
![2] Piezoresistive
• Based on the world's leading MEMS silicon
micromachining technology, the
piezoresistive acceleration sensor has the characteristics
of small size and low power consumption
• It is easy to be integrated into various analog and digital
circuits.
• It is widely used in automobile crash experiments, testing
instruments, equipment vibration monitoring, etc...
6](https://image.slidesharecdn.com/accelerationandvelocitysensor-230409214018-faf52dc6/85/acceleration-and-velocity-sensor-pptx-6-320.jpg)
![3] Capacitive
• The capacitive acceleration sensor is a capacitive
sensor with great changes based on the principle of
capacitance.
• The capacitive accelerator is irreplaceable in certain
fields, such as airbags, mobile devices, etc.
• It usually adopts the micro-electromechanical system
(MEMS) technology, which is economical in mass
production, thus ensuring lower cost.
7](https://image.slidesharecdn.com/accelerationandvelocitysensor-230409214018-faf52dc6/85/acceleration-and-velocity-sensor-pptx-7-320.jpg)
![4] Servo
• The servo acceleration sensor is a closed-loop test
system, which has good dynamic performance, a large
dynamic range, and good linearity.
• The vibration system of the sensor is the "m-k" system
, which is the same as the general acceleration sensor,
but there is an electromagnetic coil on the mass m.
• When there is acceleration input on the base, the
mass deviates from the equilibrium position, and the
displacement is detected by the displacement sensor,
amplified by the servo amplifier, and converted into a
current output.
8](https://image.slidesharecdn.com/accelerationandvelocitysensor-230409214018-faf52dc6/85/acceleration-and-velocity-sensor-pptx-8-320.jpg)
acceleration and velocity sensor .pptx
- 1. Acceleration and Velocity Sensors B3 GROUP-11
- 2. 2
- 3. Acceleration Sensor • An acceleration sensor is a device which measure how something speed ups or down. • It is usually composed of a mass block, damper, elastic element, sensitive element and an adaptive circuit. • During the acceleration process, the sensor uses Newton's second law to obtain the acceleration value by measuring the inertial force applied to the mass. • According to the different sensitive elements of the sensor, common acceleration sensors include capacitive, inductive, strain, piezoresistive, and piezoelectric type PRESENTATION TITLE 3
- 5. 1] Piezoelectric • Piezoelectric acceleration sensors measure acceleration, vibration, and shock by converting mechanical energy into electrical signals. • They rely on the piezoelectric effect, which is the ability of certain materials to generate an electric charge when subjected to mechanical stress. • The sensor consists of a piezoelectric crystal sandwiched between two electrodes. • When the sensor is subjected to acceleration, the crystal deforms, generating an electric charge that is proportional to the magnitude of the acceleration. • Piezoelectric acceleration sensors are widely used in various industries, such as aerospace, automotive, and industrial applications, due to their high sensitivity, low noise, and wide frequency range. 5
- 6. 2] Piezoresistive • Based on the world's leading MEMS silicon micromachining technology, the piezoresistive acceleration sensor has the characteristics of small size and low power consumption • It is easy to be integrated into various analog and digital circuits. • It is widely used in automobile crash experiments, testing instruments, equipment vibration monitoring, etc... 6
- 7. 3] Capacitive • The capacitive acceleration sensor is a capacitive sensor with great changes based on the principle of capacitance. • The capacitive accelerator is irreplaceable in certain fields, such as airbags, mobile devices, etc. • It usually adopts the micro-electromechanical system (MEMS) technology, which is economical in mass production, thus ensuring lower cost. 7
- 8. 4] Servo • The servo acceleration sensor is a closed-loop test system, which has good dynamic performance, a large dynamic range, and good linearity. • The vibration system of the sensor is the "m-k" system , which is the same as the general acceleration sensor, but there is an electromagnetic coil on the mass m. • When there is acceleration input on the base, the mass deviates from the equilibrium position, and the displacement is detected by the displacement sensor, amplified by the servo amplifier, and converted into a current output. 8
- 9. Working Principle • Acceleration sensors work according to the principle of the piezoelectric effect. • Piezoelectric effect states that "the external force applied to a heteropolar crystal without asymmetric center will not only deform the crystal but also change the polarization state of the crystal and establish an electric field inside the crystal. • The general acceleration sensor utilizes the characteristic of crystal deformation due to the acceleration inside.Since this deformation generates a voltage, as long as the relationship between the generated voltage and the applied acceleration is calculated, the acceleration can be converted into a voltage output. 9
- 10. 10
- 11. Applications • Vehicle safety : the acceleration sensor is mainly used in safety performance as automobile airbags, anti-lock brake systems, traction control systems, and so on. • Game control : the acceleration sensor can detect the change of the inclination angle. Therefore, it is easy to control the directions of the objects in the game by tilting the handheld device forward and backward • Tilt correction of electronic compass : the acceleration sensor can measure the tilt angle, it can compensate for the tilt of the electronic compass. • Image stabilization : acceleration sensor to detect the vibration/shake amplitude of the handheld device. • Hard disk protection : the acceleration sensor is used to detect the free-fall state, thereby protecting the mini hard disk. PRESENTATION TITLE 11
- 12. Velocity Sensors A velocity sensor, also known as a speed sensor or a motion sensor, is a device that measures the velocity or speed of an object or system. It detects changes in position over time and calculates the rate at which the position is changing. In addition to measuring speed, some velocity sensors can also measure other parameters such as acceleration, displacement, and position. They can also be used in conjunction with other sensors such as temperature sensors, pressure sensors, and strain gauges to provide a more comprehensive picture of the performance of a system or component. PRESENTATION TITLE 12
- 13. Types of Velocity Sensors Magnetic Optical Piezoelectric Gps Sensors 13
- 14. Magnetic Velocity Sensors PRESENTATION TITLE 14 • A magnetic velocity sensor consists of a magnetic field sensor that measures the changes in the magnetic field caused by a moving object • The sensor is placed close to a rotating shaft or gear, and as the shaft rotates, it generates a magnetic field that varies with time. • The sensor detects these changes and converts them into a signal that can be used to calculate the speed of the rotating shaft. • They are commonly used in automotive and industrial applications to monitor the speed of rotating machinery such as engines, motors, and turbines.
- 15. Optical Velocity Sensors PRESENTATION TITLE 15 • These sensors use light to detect changes in position and measure the speed of an object or system. • an optical velocity sensor uses a light emitter and receiver to measure changes in the position of an object over time. • The emitter sends out a beam of light, which is reflected off the moving object and detected by the receiver. • The position of the object is determined by analyzing the changes in the reflected light, and the speed is calculated by measuring the rate at which the position is changing. • They are commonly used in robotics, aerospace, and industrial applications where high accuracy and precision are required.
- 16. Piezoelectric Velocity Sensors 16 • These sensors use a piezoelectric material that generates an electrical charge in response to mechanical stress or vibration. • Piezoelectric velocity sensors work by converting mechanical energy into electrical energy. • The sensor consists of a piezoelectric material that generates an electrical charge when it is subjected to mechanical stress or vibration. • As the object or system being monitored vibrates or moves, the piezoelectric material generates an electrical charge that is proportional to the velocity of the object. • They are commonly used to monitor the vibration and speed of machinery in industrial applications.
- 17. GPS Velocity Sensors 17 • GPS velocity sensors use GPS (Global Positioning System) technology to determine the velocity of an object or system. • The GPS velocity sensor works by measuring the changes in the position of a GPS receiver over time. The GPS receiver receives signals from multiple GPS satellites in orbit around the Earth. • By analyzing the time it takes for the signals to travel from the satellites to the receiver, the GPS receiver can calculate its position on the Earth's surface. • GPS velocity sensors can provide highly accurate velocity measurements, especially over long distances and high speeds. They are commonly used in a variety of applications, including navigation, aviation, marine, and automotive industries.
- 18. Applications • Accurate and precise measurements: Velocity sensors can provide highly accurate and precise measurements of the speed or velocity of an object or system. • Real-time monitoring: Velocity sensors can provide real-time monitoring of the speed or velocity of a system or component. • Non-contact measurement: Many velocity sensors use non-contact measurement techniques, such as optical or magnetic sensors • Non-contact measurement: Many velocity sensors use non-contact measurement techniques, such as optical or magnetic sensors • Integration with other sensors: Velocity sensors can be integrated with other sensors, such as temperature sensors, pressure sensors,etc PRESENTATION TITLE 18
- 19. Thank you