I have a project where I need to sense movement(1-5mm) on 4 axles and when one of the 4 sensors move it must send a signal to a buzzer and light up a LED.(4 LED’s one LED for every axle)
Example if axle 3 starts to move it must activate the buzzer and light up LED number 3.
Can you please point me in the right direction by telling me what sensor I can use and what micro controller board will be able to do all this that I require.
Any help or suggestions would be appreciated.
What I think I need is:
Arduino board
Strain gauge x4
amplifier
Thank you for contacting RobotShop.
For the microcontroller board, we suggest you to use an Arduino board for the simple reason that you can find a lot of examples and sample codes online to help you get started.
Here is some examples :
@bdaouas
Thanks for the reply
I need a sensor that can detect very small linear movement(1-5mm)…Say I have a point A and B and they are fixed, I need to detect when point B moves closer or away from point A, and the distance I want to measure is 1mm-5mm.I have looked up IR and ultrasonic and I am not sure if they can detect so close to the sensor(1-5mm) that is why I thought a strain gauge would work well if you fix it to point A and B and when point B moves away from point A the resistance increases, but I am no expert that is why I am seeking advice…please give me advice or tell me if I am wrong.
You can surely use strain gauges to detect if a point B moves closer or away from a point A (with the appropriate amplifier) but a force/pressure needs to be applied on point B to vary the electrical resistance of the strain gauge.
The strain gauge works in a way, that when the material (on which the strain is attached on) is expanded, the electrical resistance of the strain will increase.
On the other hand, when the material is compressed, the resistance will decrease. In both situations, a force/pressure will be needed to detect the motion.
A rangefinder (Infrared or Ultrasonic) attached let’s say on point A, will measure the distance from this point to a moving point B (no need for external pressure to be applied).
This ToF Range Finder Sensor might interest you. In its datasheet, this sensor should be able to measure absolute range from 0 to 100mm.
The measurement steps/accuracy need to be verified though to confirm that it can do the job for your application.
I had a look at the ToF Range Finder Sensor and it looks very promising. Say I want to use 4 of the sensors, what additional parts do I need apart from the LED’s and a buzzer?Will this work with the arduino?
You will need the microcontroller. You can use an Arduino UNO for example.
As the ToF Range Finder Sensor Breakout Board has a 2.8V operating voltage as input and logic, it will require additional hardware for voltage regulation and level shifting.
A simpler way, is to use this ToF Range Finder Sensor that already includes its own level shifting and regulation on the board. You can find the wiring diagram and an Arduino sample code here.
In addition, as you want to use 4 of these sensors, and since these sensors are using I2C, you probably can’t use them with the same address on the same SDA and SCL pins.
Therefore, you will probably need an I2C multiplexer as this one.
