Why is it so hard to remember to use hand sanitizer between going into the store and driving back home? We tried hanging a bottle off the windshield wiper stalk, but it gets in the way and is hard to use and share with passengers. The ideal thing would be to have a hands-free pump in the car that reminds you to use it.

You don’t have to wire this to the ignition or anything — all you have to do is power it with the cigarette lighter (or straight-up outlet, if you’re lucky). Every time you turn the key, this pump powers up and performs a little song to remind you to use it. Electronically speaking, it couldn’t be simpler — an Arduino UNO reads your hand from the distance sensor and activates a servo that dispenses three short pumps of isopropyl alcohol. Check it out in action after the break.

Want a hands-free solution for the house? Just build something you can step on.

We once saw a Romeo and Juliet production where the two families were modern-day mob families with 3-piece suits and pistols. If they made King Richard III set in this week, the famous line might be: “Hand sanitizer, hand sanitizer, my kingdom for hand sanitizer!” Even if you have a supply stashed in your prepper cache, you have to touch the bottle so you could cross-contaminate with other users. Public places often have automatic dispensers to combat this, and now you can too. [Just Barran] shows the device in a video, you can see below.

Sourcing parts for projects is sometimes a problem, but right now we are betting the hand sanitizer will be the hardest component. Of course, the Internet is ripe with homemade brews that may or may not be effective based on beer, grain alcohol, or a variety of other base materials.

[Barran] has a big junk box. so he snagged an Arduino and an ultrasonic sensor. The part that is a little tricky is pulling down the pump. The basic idea is to use a servo motor to pull some fishing line. To engage the bottle, there is a small bit of plastic from a notebook cover and the fishing line goes to both sides of it. One side of the fishing line is fixed and the other is what the servo pulls.

We might have used a solenoid to push the button, but we like the servo method for its simplicity. In the end, it does look like it works well. Changing the bottle out probably requires a little surgery since there is a screw holding the plastic bracket in and you might have to update the fishing line lengths. That might be an impediment for a commercial project, but for your own use, it doesn’t seem like it would be a problem.

Fishing line is more useful than you might think. We’ve even seen it used as belts in 3D printers.