I had a blast making bristlebots with my 4th grade science club a few weeks ago, so I started thinking up new ways to make simple vibrobots to give away as gifts.
I came up with this very simple Cockroach Virbobot. It only costs about $2.50 and 20 minutes of time to make. Super cute and super simple.
Step 1: Supplies
Soldering Iron + solder
Hot glue gun
(A helping hand is nice as well)
Wire cutters or strong scissors
1.5V solar panel ($1)
Small DC Vibrating Motor (AKA Pager motor) ($1)
Two paper clips
Scrap wire (I used the ends from a couple of resistors i had cut down. They can be anything.)
Super Cute Option: Googley eyes
I bought a pack of 10 solar panels off ebay for $10. Great for a lot of projects.
I bought my motors from the online store Electric Goldmine for $1.10 each. I like the ones they have because they trigger at only 0.5V, whereas most trigger at around 1.5V. The lower trigger voltage you can get the better because it means that your roach will work under less sunlight. If you do buy from them be SURE to get the motors with the blue casing, not the silver. Silver ones suck for a variety of reasons.
If you don't want to buy these in bulk, I have a kit and prebuilt ones for sale on my website. It's a fun project you can do with kids or makes a great little gift you made yourself.
Step 2: Solder The Motor
Do the same to the other side.
You want the wires point out.
BE CAREFUL! You don't want to use too much solder, nor do you want to put your soldering iron on the tab for too long. Too much heat and you'll melt the motor.
(Another reason I love the motors from Electric Goldmine is that they have very big solder tabs that are easy to solder. You want the ones with the blue casing, the pure silver casing ones melt with the slightest touch.)
Step 3: Connect to Solar Panel
Positive and negative don't matter in this case.
I like having my motor be hanging in the middle. You can have it any which way you like.
No, you don't need anything else.
No, you don't need a diode.
No, you shouldn't try fitting a capacitor in there. (I tried, it's not worth it.)
Step 4: Paperclips
Then bend them in half. We're making nice little Vs here people.
Using the Helping Hand and Hot Glue Gun, glue the legs on.
Again, the position of the legs all depends on you and how you want the roach to stand. I like my roaches short and slightly angled forward. This way I can point him at the sun for max power.
(As someone was so kind to point out, don't let the paperclips tough the wires the run to the motor, otherwise you'll get a short. If you're worried, just throw some hot glue between the legs and the motor wires.)
Step 5: Enjoy!
To make your roach extra cute I usually add on some little antennas via a single strip of thin wire.
You can also go full crazy and add googley eyes to make him extra personable.
I've made quite a few and given many away. Below are a few I have in my room (including one with a capacitor, something that didn't work at all for me) to give you an idea of different ways to do the legs.
If you'd like one I have some for sale on my website, etsy store, and available as kits.
If you want a cheap and easy project you might as well put some together.