I want to use a sensor to detect force for a small robotic gripper. I tried using 20kg FSR(Force Sensitive Resistor), but it is not very accurate. Are there any other sensors that can be used?
Thank You
Yes but the sensor should be able to detect force as low as 0.1N. Also, it would be great if you could suggest any other way, I am planning to make something similar to an exoskeleton but just for 1 finger. So I need to detect force and stop the actuator in time to prevent squishing.
That sensor can be configured a number of ways, including being able to detect force as low as 0.1N Read the datasheet AND the integration guide. Use the recommended circuit and a puck.
0.1N is a problem for a 20kg (~200N) FSR.
So what is the range of force you want to detect, and at what accuracy?
Thanks everyone for all the information, the range of forces I want is 0.1 to 100N(even 60-70 is fine). Shohld I buy a 6 or 10kg sensor?
wvmarle:
0.1N is a problem for a 20kg (~200N) FSR.
This is not necessarily so. By varying the feedback resistor and drive voltage of the op amp circuit, the Tekscan A201, for example, can be configured to read force ranges of 0N to 4N, 0N to 111N, 0N to 445N, and even 0N to 4450N. Or any range in between. To the specs noted in reply #1, so they say.
In any case, I recommend following Tekscan's advice: "always contact our support team before purchasing your sensor – we will ask the right questions to make sure the sensor you choose will achieve your specific goals."
Also, since the OP wants at least 1:1000 resolution (0.1N to about 100N), a better ADC than the 328's 10-bit will be needed.
Sgr41:
Yes but the sensor should be able to detect force as low as 0.1N. Also, it would be great if you could suggest any other way, I am planning to make something similar to an exoskeleton but just for 1 finger. So I need to detect force and stop the actuator in time to prevent squishing.
You'll need a small loadcell to get anything like that range with repeatability, and you'll probably have to correct for gravitational forces on the gripper itself as 0.1N is only 10gf.
Thanks everyone, all the information was really helpful, I am trying a few things and hopefully it works. @MarKtI cannot use a loadcell because i am going to mount it on a glove, it needs to be flexible lke the FSR but thanks for the info i got to learn something new.
I also wanted to know if the sparkfun myo muscle sensor/emg sensor would do the job. I know it would work if i just want to start and stop the motor but can I use fuzzy login with it to adjust the grip proportional to the emg signals?