Sen-14209 PocketGeiger Type 5 on a Rocket Flight

Hello,

I am building a cubesat that will be launched aboard a rocket, inside a locker in the pressurized crew capsule. One of the onboard experiments calls for radiation level sensing. I see that the PocketGeiger Type 5 (SEN-14209) needs to remain still, otherwise it will give false readings. The cubesat will be experiencing high levels of vibration, acceleration, deceleration, and freefall throughout the flight. Is there any way to differentiate the noise from genuine radiation readings?

Once the rocket engines shutdown, and the capsule disconnects, there will be moments of weightlessness and free-fall. Do you think that the sensor will be able to pick up usable readings during this period? It will be approximately 300km in altitude at its apogee, and outside the atmosphere, so hopefully vibrations will be minimal for a little while.

We also do high altitude glider experiments and regular high altitude balloon flights carrying cubesats up to 33km in which the sensors will undergo vibration, acceleration, deceleration, and free-fall. We use Arduino for all of these experiments, as they are cheap and accessible for teachers and their students. The PocketGeiger Type 5 would be perfect for our experiments, as it is small and light-weight. I just need to figure out a way to overcome the vibration issue.

Any advice would be greatly appreciated!

I’m not going to be able to answer for sure…but I would reason that if it survives the vibrations experienced during launch + point of max accel, it would likely work fine from when/where the vibrations slow down to a level that doesn’t interfere?

If you already have some vibration data, I suppose you could feed that to a speaker/geophone/something that vibrates at the same amp/freq, and shake the hell out of the geiger here on the ground to test its potential reliability?

Third, you could always just test it and see! heh…isolate/dampen it as much as possible and hope for the best

Finally, it might be more helpful to ask the MFR https://cdn.sparkfun.com/assets/learn_t … 501401.pdf

I am in touch with the founder of the company that designed this particular PIN diode sensor. He said, “The pocket geiger contains a vibration suppression circuit. It is effective against pulsed sporadic large vibrations. For example, car vibrations. However, if there is a steady or constant vibration, such as a vibrator, the suppression circuit is always active, so the radiation measurement cannot be made.”

I can’t find a reference to PIN diodes being vibration sensitive, and the PIN diode data sheet posted on Sparkfun does not seem to mention vibration sensitivity.

So, you really have to wonder why the detector assembly is so sensitive to vibration. And, what is it on the assembly that detects vibration and produces the “noise” signal?

Seems like a major drawback to the use of this detector, possibly rendering it useless in rockets or small planes. If the manufacturer would provide some insight, that could be very interesting.