How to Choose an Acceleration Sensor?
Analog output vs digital output
This is the priority parameter to be considered, it depends on the interface between the system and the acceleration sensor. Generally, voltage of analog output is proportional to the acceleration, for example, 2.5V voltage corresponds to an accelerated speed of 0g, 2.6V voltage corresponds to an accelerated speed of 0.5g. Digital output usually uses pulse width modulation (PWM) signals.
If the microcontroller you use has only digital input, such as the BASICStamp, you can only select the acceleration sensor with digital output. However, you have to occupy an extra clock unit to process the PWM signal, which is also a burden to the processor.
Number of measuring shaft
For most projects, the acceleration sensor with two shafts is able to meet most applications. However, for some special applications, such as the controlling of UAV, ROV, an acceleration sensor with three shafts is more applicable.
Maximum measured value
If you just measure the dip angle between the robot and ground, an acceleration sensor of ±1.5g is enough. However, if you need to measure the dynamic performance of a robot, an acceleration sensor of ±2g is enough. If your robot may start or stop suddenly, you need an acceleration sensor of ±5g.
Generally speaking, the more sensitive the better. The more sensitive sensors are more sensitive to acceleration changes within a certain range, output voltage changes are greater, thus the measurement is easier. More accurate measurement values can be obtained.
The bandwidth here refers to the refresh rate actually, namely the quantity of readings in per second. For the application to measure the dip angle, a bandwidth of 50Hz is enough. However, if dynamic performance is required, such as the vibration, you may need a sensor with a bandwidth of more than 100 Hz.
For some Microcontrollers, the resistance of sensor connected must be less than 10kΩ when carrying out the A/D transformation. For example, the resistance of Analog Devices's analog acceleration sensor is 32kΩ. It can't work normally on the PIC and AVR control board. So it’s suggested to read the controller manual carefully before purchasing the sensor, so as to ensure that the sensor can work normally.