Lost and Found

In our den, we have an entire wall covered with bookshelves loaded with hundreds of books.  Some of the shelves are over 8 feet high.  We use the top surface of the bookshelves to store different items like pictures and our collection of Menorahs.


The Valley of Lost Items

In the corner where two of the bookshelves connect at 90° angles, there is a gap of approximately 10” x 10” between them that goes all the way down to the floor.  Two years ago, as my mom was dusting the top of the shelves over there, she accidentally knocked over one of the picture frames and a menorah. They both fell right into that opening and all the way down to the floor. “Oops,” mom said, but then she forgot about it.  When Hanukah came this past year and my mom couldn't find the missing menorah, she suddenly remembered her oopsie moment from the year before.
She complained that getting it out was going to be a real hassle since we’d have to first remove the books and then the shelves themselves just to get back there. “Oh well,” mom said, “unless one of us is going to grow octopus tentacles, we’ll just have to wait until we move out.”

“Why wait,” said my Dad, “when the mad genius (i.e., me) can invent a super-fabulous picker-upper thingy right now?”  As usual, he had his rules though. His condition was that the books and shelves must remain where they are and that I could not use my hands to pick up the fallen items.  Not sure if he was picturing me hanging from my ankles and being lowered down into that crevice to pick everything up by hand, but no matter.

Anyway, I got to work and with his help designed a robotic arm (we call it the RCRA – Remote Controlled Robotic Arm).

I figured that in order for it to be useful it should be able to achieve the following:

1. Have remotely controlled claws
2. Have a source of light so we can see in that deep and dark corner
3. Provide images in real time so that claws can be used accurately
4. Have a way to raise and lower it up and down without hitting anything on the way

As you can see from the plans, The RCRA has a flashlight, a wireless camera, and two claws that are each controlled separately.
  
RCRA Plans (Remote Controlled Robotic Arm)

After several weeks of work (and a lot of help from my dad) the robotic arm was finished.  For its construction, we salvaged many parts that were lying around the house (like my sister’s broken remote controlled car, motors from one of my older robot projects, etc.).


RCRA Details (Arm with the remote control)

The whole arm turned out to be small – 10” long x 3” wide and only weighs 9 oz.  The claws can open up to 5” so that it can grab and lift very wide objects.  Each claw is controlled by its own motor so they have a lot of grabbing power.



After experimenting with it for a while, we decided to take it for a test drive behind the shelves.  We powered the arm and lowered it.  After a short descent, we started seeing images and before long I could see our long lost menorah and picture frame displayed on the laptop screen.


Video image showing a menorah and picture frame

The video survey worked out so well that we decided to lift the items immediately.  It took several tries (as you can see in the movie). The RCRA hooked onto the menorah but then as it was lifting it, the claws slipped and the menorah fell.  That turned out to be a good thing actually because it made it easier for me to position the claws around the shaft.

 
Recovered Items

After that it only took a few more seconds and our lost and forgotten treasures—cobwebs and all—were recovered. I love when technology works!