Day 4: Trash Can Caddy

My boys are not very reliable with respect to taking the trash cans from the house to the edge of the street and back.  It's not a very hard thing to do, but I get much pushback (we do have a relatively long driveway) whenever I ask them to do it.  What I need is a rugged device that'll do it for me!

The Trash Can Caddy! (red = wheels, orange = control box, blue = support structure)

One Step Beyond

I have a trash can much like this one.  I envision the Trash Can Caddy (TCC) to work like the following:

• The caddy slips under the trash can with wheels on the outside of the can.
• Under normal, resting position, the TCC wheels are not supporting any weight, so that the can remain stationary.  Alternatively, if you have multiple smaller trash cans, this system could be built into one of these caddies.
• When directed (likely timer-based given that most of us have schedule trash delivery), the TCC lifts the front of the can slightly to make its wheels load bearing.
• The TCC travels down the bottom of the driveway using accelerometers and GPS backup (think geo-fencing to ensure the TCC doesn't go out into the roadway) to direct its path.  The user would have to take the can down and back on several training runs to ensure that the TCC knew where and how to go.
• The final spot for the can it determined with high accuracy by using a RFID pad attached to a post that is sitting just off the side of the driveway that the user wants the can to be placed.
• The TCC senses when it's been emptied and makes its way up the driveway about a minute after that's happened.
• The TCC sends you a quick note that it was successfully emptied and returned to it's storage location (also using an RFID pad).

There are a number of issues that could stand in the way of this ambitious product:

• Safety: you'd have an autonomous vehicle roaming your driveway.  It could run somebody over or hit a car.  On the plus side, it'd not need to move fast (maybe 6" per second).  It could use ultrasonic sensors (like cars) and current sensors on its motors and be sensitive to turn off.
• Stability: you really don't want the TCC tipping over on it's way to the road.  Good sensors, software and a control system should help keep things rolling in the right direction.
• Wear and tear: your garbage can is going to get flung up on a truck to be emptied.  The TCC has to be rugged enough to withstand repeated pounding.  Sensors and the control box may need to be located on either side to avoid this problem.
• Battery life: The system doesn't need to be particularly light, so perhaps you can pack a reasonably good size Li battery into this.  That said, trash cans are often stored outside where it can be quite cold.
• Inside storage of cans: Growing up, we used to store our trash cans in the garage.  For this system to work, you may need to include an automatic garage door opener interface.  But that would make it even cooler.  The complication could be tight maneuvering around cars.
• Non-paved driveways: maybe solved by using off-road tires.
• Snow: In a measurable amount of snow, the device would probably not work.  The app could perhaps alert the user when snow is forecasted at their address and force the user to affirmatively say that the path is snow-free.
• Ice: the TCC may just get stuck sometimes.  As long as it doesn't tip over, not the end of the world.  User is notified whenever this happens.

Two Steps Beyond

Here are some, mostly marginally useful thoughts on further improvements:

• Set the accelerometers to be on guard when the can is back at it's home location.  Chirp or alarm if animals are entering.
• Better yet, add a locking mechanism on the top.  Quick one-button unlocking and then automatic relocking, to avoid animal intrusion in the first place.  Much better than the bungie cord system that I'm using now.
• Based on the amount of force required to lift the front of the TCC, measure and track the garbage produced by the household.  Present data in an easily understood way.  Compare to their neighbors and the rest of the TCC users.  Make suggestions on how to reduce.  If you are like me, you can also measure recycling weight and make the user feel good about how much avoided landfill they've offset.