Let's Make Robots! | RobotShop

An easily tunable sensor mounting system

Accurate and simple way to mount a sensor

Let's say you have a sensor on your beloved (or hated) bot.

You want to fix it so you can easily tune the distance between it and the floor (for example).

You can use a bunch of screws and add more or less washer to it, but what if you want something accurate because with washer your accuracy will be limited by their thickness?

This is what i did:

In my case, in my current test platform, i wanted to use a ps2 mouse and they can be quite stubborn with the distance from the floor.


I was thinking about it while playing with a pen in my right hand. And then, (macgyver theme song) i had an idea.

Maybe i can use some spring to fix the mouse, so if i want to tune it, i just have to screw/unscrew some bolt.

What i used:

A bunch of bolts and nuts:

Some cheap bic pen, 3euro for 4:

Bic pen

I had to fix the mouse on another sheet of epoxy because i add to lower everything:

Used some nylon washer to avoid some nasty shortcircuit :

Now, just extract the spring from the pen:


Size of the spring in cm (0.9055 inch)


Put all the pieces together:


Closed up view:

Now, if you want to raise your sensor, juste screw a little at a time, and if you want to lower it, just unscrew, easy.



Thing that can be updated:

I wanted to try thermoforming some plastic to make the white mount in the photo, next time i'll take more time to do something better.

I'll drill slower too, because plastic tend to melt really fast, and i'll use a bigger drill bit, i threaded the plastic when using a too small one.


ps1: i'm so used to spam ctrl+s to save when i write, that's annoying...

ps2: next time, i'll remove the dust BEFORE taking photo

ps3: the first photo looks a bit crappy, dunno why, higher res next time ?

ps4: my first contrib to lmr, yeah!

ps5: dont know if this should be posted as tip/walkthrough

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Cool tip :) Inspiring, thanks :)


Thanks to your tip, I was able to solve a problem that had been annoying me for some time. 

My bot kept getting stuck on those metal "deviders" on the floor that seperates wood flooring and capted areas. Know I can just tighten the screws and change to hight that the bot can cross over. 

And keep us updated on your project! It looks like you are going to use a mouse to track the movement of your robot? Maybe mapping? 

This is a great tip!  And great photos too.  

Like you, I also had to make a system to adjust my sensors(to keep them parallel with the ground, my robot is based on an R/C car not a purpose built robot base). However, I chose a slightly different approach.

Instead of using a spring, I used an extra nut. Saves a couple of fine ballpoints (destroying a pen is an awful thing to do with such a powerful device; the pen, after all, is mightyer than the sword ;-) ). I must admit the springs do look good though, and it's nice to be able to adjust with just one nut.

However, it might be a better solution if you have the sensor platform mounted higher than the rest, because then the springs will have to be strong enough to carry the platform (and everything mounted on top of it).

Just putting it out there!