Our work on this idea started all the way back when we were coming up with problems in the world and writing them on sticky notes. What our sticky note said was the snow takes too long to pick up. Out of all of our problems that was the one that we liked the most.
We came up with many different solutions to this problem. We considered ideas such as using heat to melt the snow, dumping the snow in a big hole, using fans or covers to keep the snow from falling on the driveway in the first place, etc. The heating idea took too much energy; the big hole was too expensive to dig, and we were uncertain about the fans and covers. So we decided to focus on making a robot that would replicate the functionality of a common snowblower. But building an autonomous snow blower is challenging because one must be very careful not to throw snow in the wrong direction and damage objects. So we came up with a design that separates out the throwing aspect into a simple stationary device so that the roving autonomous robot is only tasked with collecting and dumping snow.
Our first step to building this prototype was to decide on which material to use. Since Nico had been in Lego robotics for 7 years we decided to go with what we were most accustomed to. We first built a mechanism that would move up and down to lift the snow. We used a collection of gears to accomplish this. After building this part of the robot we had to find something to be able to move it. We used a lego technic set that was an RC car. This car included suspension and big wheels for traction over uneven surfaces. The final step to finish the lego base of the robot was to connect the two pieces together. To even the weight of the car we attached the Mindstorms computer towards the back to prevent it from tipping and steering off course.
After piecing together the parts of the robot, we focused on creating the stationary thrower. To be able to start this we needed to look at a regular snow blower to be able to better understand the process. We found that the part that throws the snow includes something called an impeller. This is a piece behind the auger that spins very fast to throw the snow up and out of a spout/tube. We decided to separate out the impeller and replace the auger with a slope that the snow would slide down into the impeller. Since we clearly could not use legos for this part of the project we decided to use an electric motor and a large round PVC pipe to mount it on. To mount the motor we needed it to not be angled, so we sanded the place in which we would mount the motor flat. For the part that spins and throws the snow up the tube, we decided to design a 3d printed model on Tinkercad and print it. This way we could get exact measurements so that the arms of it would not hit the side of the PVC. For the motor to be able to spin this piece, we needed to have a motor shaft extender. When this piece arrived, our 3d model had to fit tight on it to keep it secure. As this impeller was spinning, it needed a place to release its materials; for this, we cut a part of the PVC out for the fake snow to escape. From the hole, we connected a long tube of water bottles to project the snow out of the device.
Throughout the process, we had many problems with the impellers. The first impeller, which took 16 hours to print, was unfortunately dropped shortly after it was removed from the machine. The second impeller worked well, but the motor was not fastened tightly enough, and so catastrophe struck. The motor started to move off center, causing a wobble, which caused the impeller blades to collide with the PVC coupling which then destroyed the impeller instantly. From this experience, we learned that the motor needed to be well mounted to prevent any movement. This caused us to reprint the impeller yet again (as well a spare impeller) the night before the Innovation Expo. We then ensured that the impeller was correctly installed before the Expo.
As it was the summer, there was no snow available to us. We improvised by buying some fake snow on Amazon called Snow Wonder which provided the effect of real snow for the Expo. Snow Wonder is a non-toxic superabsorbent polymer that creates a snow like substance when mixed with water. After feeling it for the first time, we decided that it was so like real snow that you barely tell the difference between real and fake snow.
After our project was finished (or so we thought) and ready to test we realized that the thrower’s slope was not steep enough for the snow to slide down. Since we found this out the day before the Expo we ended up pushing the snow down with our hands. In the future, we will make the slope steeper. We also ran into a different problem. This was that the lego mechanics that should've lifted the snow did not lift high enough for the snow to reach the top of the thrower’s slope. In the future, it will be stronger and will be able to lift higher. Once we expand upon all of our ideas we will make our project into a more finished product that hopefully, people will want to use. Who knows, we might even change the whole project since innovation is a crooked path.