The Human Hamster Wheel

Because I have already graduated, my username is soon to be deleted, so I thought I would write one last post updating everyone on the hamster wheel.  First of all, the hamster wheel is up and running and it is spectacular!!!!  The generator is hooked up and generating power.  There is also a circuit (that I made for advanced lab class) that monitors the output of the hamster wheel and lets you verify how much voltage you are producing.  This summer we had a frame built for the generator, and it bolts onto the steel frame below the base holding it in place.  We also made a poster about the hamster wheel and other alternative energy sources. 

This summer Dr. Sheldon and I used the hamster wheel in a presentation during Alumnae Weekend.  Unfortunately that meant we had to carry the wheel up the the Psychology Building through Main Hall.  And then it was too big to fit into Psych 101!!!!  So then the wheel ended up living in the hallway of the Psych Building for a while.  The hamster wheel also made quite a few appearances this spring semester for admissions events.  The last week I was at school, we moved the wheel back to the lab, and I realized that we never officially named the hamster wheel.  So I dubbed the wheel Henrietta, after Joseph Henry and henry, the unit of inductance, because that is kind of related to how a generator works.  So now we have Henrietta and Al (and his friends the crab and the ebola virus).

Thanks again to everyone who worked on the wheel.  It was definitely a team effort!!!  Building the hamster wheel was one of my favorite things that I ever did in college, and I will cherish the memories always.  Goodbye everybody.

Now for an update on the wheel.  We have had a lot of smaller build days in the last couple of months and finished a lot of fitting things together that needed to get done.  We repainted the base, because we wanted it to look a little more professional than it did when it was all the colors sprayed on everywhere.  So now it is a more organized multi-colored base.

 We painted the metal spokes and fixed a gap in the mesh inside of the ring.

Then we attached the metal spokes, replacing the wooden ones that were only meant to hold the wheel in the right shape until the metal ones were ready.  This was a little difficult, because we had to avoid all the metal plates that were reinforcing the ring and in some cases we had to go back later and drill through those metal reinforcing plates to attach the rest of the bolts.  

We also had to work out how to attach the pillow block bearings that support the spokes holding the wheel up.  One side has to be attached, but one side must be removable so that the hamster wheel can be separated from the base.  We ended up drilling into the top of the base and bolted one pillow block bearing down.  On the other side we drilled into the top of the posts as before, but then we cut the tops from two bolts and attached them like two pillars that hold the pillow block bearing in place.  When the pillow block bearings are in place, nuts keep them from coming out of place, but the one side is still removable for transportion purposes.

 Then we finally got the wheel spinning for the first time last December.

Since then we have had a lot of little builds fixing little things that needed to be fixed mostly.

Then we had to get working on the generator.  We designed it, ordered the parts, had some pieces machined, and got it set up and running just 15 minutes before the TV crew came to interview us.  You can watch the story at this link:

http://www.wset.com/news/stories/0208/499977.html

I think one of the flyers to get people to work said that there would be fame and glory, and look, I was right.

The generator is up and running, and it does light up some lightbulbs, but it’s not quite right yet.  The metal frame that attached the pulleys and the generator is a little weak, and so unless Dr. Sheldon is standing on it, it starts to bend upward.  Then the belt is no longer tight enough, so the pulley stops turning and everything gets messed up.  We figure that if we attach a metal bar under the metal sheet, then it will keep the metal sheet from torquing upwards.  We are also going to add a second bearing to stabilize the axle.

When we first set it up, we also had it just stacked on piles of books, so we still need to build a stand for the generator and maybe be able to bolt it to the metal frame at the bottom of the hamster wheel base so that it will not slide around at all.

So that is where we are now.  We have a couple more things to get done before it is good to go, but we are doing an admissions thing with it this weekend, and then we are trying to somehow figure out how to incorporate it into the Science Day.

Thanks to everyone who has worked on the wheel, and everyone who has supported us and inquired into the wheel.  We are really proud of it!!!!

Oh, I forgot to mention that Amanda made us a giant hamster named Al who spends a lot of time hanging out in the wheel.  So now we need a really good name for the hamster wheel.  So if you have any ideas, please comment or email us.

It turns out that we had some learnin’ to do about sizes, and names of parts. Other than the wood with metal reinforcements for the wheel, we decided on the following:

Generator driver parts:
Pillow block bearings
Size 4L, V-belt pulleys (2×10in, 2×1.75in)
½ in axle/bore size

Hamster wheel special parts:
5/8in threaded axle, pillow block bearings
4 spokes: 1.5in square tubing, machined end fittings, welded to ends and axle

By accident, cut hwheel axle too short, but since it is threaded, we machined a “nut” that is attached to a ½ in axle (to go to pulley). It would have been easier to keep one side of the axle sticking out so that it was long enough to go right into a pulley, and get a pulley with a 5/8in bore.

The lab manager, Amanda, made a hamster of appropriate size, named Al. We will eventually post pictures.

See picture of what it will look like:

Physics major, Carly Torisky ‘06 thought up the Human-Sized Hamster Wheel (HSHW) when she was a junior.

She argued that we make hamsters run endlessly without getting anywhere for our entertainment, and perhaps we should pay them back by running on a hamster wheel that generates electricity to light and heat their cage. 

Many people ask “why would you build a Human-Sized Hamster Wheel?” sometimes with surprising disdain or disbelief.

I am sure we have all heard of physics groups and classes in school building trebuchets or catapults. They are planning on storming a castle about as much as we are planning on giving extra large hamsters exercise.

In both cases, we are building a device in order to get the experience of working together as a group, the experience of working with our hands, the experience of engineering a large and complex structure. The group work aspect has been very important for the college, especially this year; the build days have been open to the college community, and we have had an amazing amount of support and teamwork from first year men and women and upper-class men and women alike. 

In addition, energy conservation and alternative sources is a central topic in the public eye these days; in the case of the HSHW, not only is it a group design and build, but we can use the device to demonstrate and educate about alternative power sources and conservation.

The HSHW is hooked up to a generator, and when a person runs on the wheel, they will be generating electricity that can be used to power household items. In addition, the system can be switched to a solar panel, so that users can compare power generated by human energy to power generated by solar energy.

And all else aside, the Human-Sized Hamster Wheel has been just plain fun!

http://physics.randolphcollege.edu/sps/rchwheel.mov

I got a little behind on the blog with all the end of semester busy-ness, but I will soon be caught up again.  This building day we had quite a few tasks to complete: finish attaching all the braces, fix the metal base, fix the wooden base, paint both the wheel and the base, attach wire mesh to the inside of the wheel, and attach temporary axels.

First thing we had to get the rest of the braces on the rungs attached.  Last time we ran out of screws, so Winncy and Cat finished up today.

While they worked on that Yanpainq worked on fixing the metal frame.  The corner pieces were a bit too long and we were worried about someone tripping over them, so he cut two of them in half and reattached the pieces to the four corners.

We also had a slight problem with the wooden base.  Last time we accidentally attached one of the side supports so that the wooden posts didn’t quite fit right in the metal frame.  We wanted to remove the old side support and reattach a new one making sure that the post fit better.  The point of the metal frame was to absorb the pressure from the wooden posts when the wheel was in use, but it couldn’t do that if it didn’t fit quite right.  First we removed the old side support.  We measured, drilled the holes, and attached the new side support just like before.  We also cut off the edges with the Saws-all and sanded it smooth.

We spent a lot of our time painting.  First we painted a primer onto the metal parts on both the base on the wheel.  Then we got to the fun part of painting.  We decided to paint the base a kind of multi-colored chaos pattern, which was quite a bit of fun to paint.  Ready, set, go!!!!

After a lot of paint wars and chaotic painting and breathing in of paint fumes, it looked kind of like this:

The professors stayed safely out of the paint fumes and off to the side to take pictures.

Fortunately when we moved on to the hamster wheel, we painted it in a much more organized fashion.

In case you can’t tell, we are kind of going with a rainbow theme. =)

After we finished painting the wheel, we had to attach the mesh around the inside.  This is to prevent people from getting their foot caught between the slats and is especially important if we let children run on it.  After a lot of team effort, we finally got the mesh attached.  Unfortunately though, we ended up with a little gap in the mesh that has to be fixed later.

Then all we had left to do was to attach some temporary axels.  We had metal ones fabricated, but we wanted to attach wooden axels to hold the wheel in the right shape.  It tends to sag under its own weight, so we had to force it into a circular shape to fit in the 76 inch axel pieces.  Then Dr. Sheldon got to use his nail gun (now that it is working again) to attach the axels.

Of course we had to paint those axels too, so that they didn’t feel left out and then we touched up the paint on the wheel a little bit.  Finally, we posed for a picture in which we tried to fit as many people as possible into the wheel.

Today’s workers were Cat Khoo, Winncy Cheung, Yanpainq Oo, Reeju Pokharel, Nema Marjana, Kacey Meaker, Tatiana Toteva, and Peter Sheldon.  Thanks to everyone who helped today.  Almost done!!!!

Dr. Sheldon and I went shopping again for one of the last hamster wheel builds.  First we returned some of the little metal plates that we were going to use to brace the inside corners before we decided to use the T-braces and the angle braces instead.  Then we had to get another 2″ x 6″ to fix the one brace on the base that was kind of messed up.  And finally, my favorite part, we got to pick out paint so that we can paint it tomorrow.  I decided that we should paint it rainbow colors, because it will look really cool when it spins.  And also, the colors have to do with light and we are comparing it to solar power, so it seemed related.  Rainbows are also just pretty and physics-y, so it seemed like a good idea to me.  We picked out six colors for the rainbow and got some primer for the metal parts.  I hope it is a nice day tomorrow, because we are going to be painting for a while.  I’m really excited!!!!

I almost forgot that we applied for a grant proposal to support the building of the hamster wheel.  We applied for the Sigma Pi Sigma Undergraduate Research Award.  According to the website, “The Sigma Pi Sigma Undergraduate Research Award program provides, on the basis of an annual competition among the active Chapters, calendar year grants to support local Chapter activities that are deemed imaginative and likely to contribute to the strengthening of the SPS program.”  It was kind of stressful getting the grant proposal written out, because we were also doing one for the Science Day at the same time.  It’s kind of hard, because you want to write the best grant possible, but it was kind of hard to know what they are looking for and if our project is going to get funded or not.  But hopefully we will get funded and if we don’t, it will still be good experience for me to have worked on it.  Cross your fingers. =)

Today we had a mini-building session, because some people were coming to take pictures of us for college publicity type stuff.  The photographers seemed minorly disappointed that the wheel was not up and running, but they still stayed to get some pictures.  It was too crowded in the first floor lab, so we wheeled the hamster wheel out to the back porch of Martin to work on it.  We didn’t really want to lay it down, so we worked on it while it was upright.  They took some pictures while we attached a couple more brackets and screwed in some of the missing screws on the existing brackets.  It was kind of funny that every time we started to screw something in, the wheel would move or slide away.  Also, the photographers seemed more interesting in us pretending that we were working than seeing us actually working, but I guess that’s how it works.  Then it started pouring down rain, so all of us crowded under the overhang trying not to get too soaked (or electrocuted from our power tools).  Then it was just about time to go, so we took the (now slightly wet) wheel back to its home in the lab, and went to warm up in the physics lab/office.  Hopefully we will get some more of the work done soon so that the wheel can be finished by the end of the semester.