@Steve, You could easily use the crash sensor Richard linked to and you would only have to use one or two per side. However you would have to place them under a toggling panel with spring clips under each side to keep it level and armed. Very much like a Roomba uses with it's front panels. That way when K9 turned a corner and bumped the crash panel at any point along his side it would push in that panel and activate the switch.

That is using it with a pull-up resistor... It will work without one however (I have used them without a resistor so I can confirm that it does work sans resistor)... Remember they are basically a variable resistor all by themselves... Since you were going to use it in a go/ no go (on/off) situation I figured you weren't looking to use them linearly..... However, a 10k resistor will give it more stable (linear) readings. I am not sure if pin "float" happens on the analog ports of the ezb, but I do know it happens on the digital ports... A pull-up resistor will control any pin "float"...

That's great to know. Thanks Richard. So a little trial and error to help dial the readings in to what I need, and all should be well. I have a few 10k resistors knocking around should I need to use them for reading stability as you mentioned.

Thanks again.

@Dave depicts 2 different ways to use the flex resistor... The first on has it using a 10K resistor to pull high. The second picture with the arduino shows a 22K resistor and the flex being pulled low... You'll have to see which one works better.... One way may work better than the other... I have only used these with my old V3 so I am curious how the 3.3v ezb4 analog port will affect how they preform....

Humm, good to know these can be used without a resister.

Yes, I'm also looking forward to seeing how this works for you also. There are lots of uses for these. I've read that the readings from them are a bit hard to read if you use them for linear readings. Seems they read slowly at first and then when they get to the last 20% of the bend they really take off.

Readings from the ADC ports on the EZB do float badly. I'm using all of mine as an on/off (high/low) switch so it's not an issue with me. I've been wanting to add a pull up resistor to one just to see how well it stabilizes it.

That's cool. I'll have a play around when I receive them and post the results. Over the next week or two I'm going to strip out K-9's entire electrical system to re-wire/retrace everything, add additional sensors (hence the flex sensors), replace the damaged acrylic panel, and give him an Acer W3 tab for his display screen.

Lucky dog!

Tell me about it, lol. Well he has been a good boy so he deserves it.