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SunTrial: Final Documentation

See the final documentation for our solar-powered game at www.suntrial.com. Watch the video below for footage of people playing the game and having a blast!

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Sundisk: Update

Circuitry:

Initially Becky and I thought that we would use a miller engine to power our Sundisks, but after trying four motors and having no luck getting them to spin, we decided to simplify the circuit to include just the solar panel, capacitor, and motor (as well as a switch to start/stop the spinning). The new circuit looks like this:

The 25V capacitor seems to give the motor enough of a jolt to start spinning, and the 1F capacitor keeps it spinning for a while, even if the intensity of the sun lessens. 

This video shows the simple circuit in action:

Gameplay:

We were able to play test our game mechanics in our games class. The rules we used were pretty simple:

  1. 2 teams of 4 people, 5 disks.
  2. Players run around to check in on disks.
  3. When a player reaches a disk they can either flip the disk over or roll the dice to randomly change the disk’s score.
  4. You can not guard the disks; you must check on a different disk before returning to check on the same disk.
  5. You can tag players from the opposite team while they are in the process of checking the disk; when this happens, both the tagger and the tagged must leave that disk to check on another. 
  6. The team with the most points tallied on the disks at the end of 3 minutes wins the round!

The general feedback was positive; people seemed to really enjoy the game, and the gameplay was pretty smooth overall. There were some comments about knowing when a player was “at a disk” or not, and it seems as though that can be easily resolved by better defining the checking space. Number of players, timing and spacing of the disks all seemed to work pretty well.

Construction:

The construction of the disks is going rather slowly, but they are looking really nice! This was my first foray into laser cutting, and I am now addicted. Here are some pictures of our disks in construction.

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Final Project: Sundisk

Becky’s image of our concept.

Proposal:

For our final project in Big Games and Sustainable Energy, Becky and I are working on a solar-powered game.

The main game pieces are going to be solar-powered disks that lay on the ground. One side will power one team’s counter, and when flipped the opposite team’s counter will be powered. When enough light has been captured (enough energy is stored) this will trigger the motor to turn a bit and increment the team’s counter.

Multiple disks will be in the play area, and players will need to run around and flip disks over to catch light advantageously for their team. The team with the most points after a period of play will win the game!

Strategy:

Strategy enters into the game because each disk will have a solar panel on each side. Team counts can go up to a point before they start going down again. Players will have to determine what will be more beneficial for their team: flip the disk so that their team is gathering light (and hopefully gaining points) or flip the disk so that their opponents are gathering light (and hopefully losing points after passing the threshold). 

Metrics for success:

Becky and I have fairly simple metrics for success.

Materials:

We are as of yet unsure what materials we will specifically use for the construction of the disks, but we know we are going to make a Miller Engine as outlined by Solarbotics. Ideally we’d like to use a dual-shaft motors inside each disk (so we can display team points on both sides of the disk), something like this motor.

Here is a list of possible parts for the miller engine:

Becky’s initial concept post for this project can be found here.

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Beambots: The Creeper

Resources and parts:

Please note: The parts listed above are probably not ideal for this circuit. However, they are the ones that I used!

Process and further information:

I created the circuit on a breadboard first using the voltage detector with part number 3812s. This made the circuit slightly different in that I needed to the diode to go from power to the detector and not detector to ground (as in my final circuit). I also needed to use a PNP transistor instead of an NPN transistor, and the motor needed to go between the transistor and ground as opposed to between power and the transistor. It’s equally as easy to build either circuit, so depending on what parts you can find build either one! Also, the TC54 works exactly like the one Solarbotics recommends, but was easier to come by (at least in my experience). 

Here is an image of my final circuit on the breadboard:

Breadboarding was relatively easy; the hard part was freeform soldering it into a shape that would stand up! I had to put the circuit together several times before it worked and looked somewhat tidy!

Next I attached the solar panel with a little solder and TONS of hot glue (my favorite electronics accessory!). I added 1/4” audio plugs on the corners to stabilize the beambot and help it stand up; this was a good idea for stability, but added to the weight of the already heavy robot, and ultimately made it very hard for the motor to turn.

Here is the final completed beambot. I added some flags for flourish, and called it “The Creeper” because of its sluggish tendency.

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A Week in the (Relative) Dark

The assignment: Either build your own device that uses kinetic energy to run itself or some other device, or replace something in your life with a pre-made device that uses to kinetic energy as a power source. 

Initial concept: Initially I wanted to replace my bathroom light with a light that was connected to my bathroom door. Because the bathroom door can provide a lot of torque, I thought it would be possible to attach a motor with a lot of gears so that when you opened and closed the door just once it would turn the motor enough times to turn on a small light for a few minutes. This would eliminate the need to turn on the bathroom light.

Results: In short, this didn’t work out for me. I ended up purchasing a motor (above) that was pretty powerful and could have certainly handled powering a light for ten minutes without me having to turn away for hours. However, without additional gears it would not have been able to power a bright enough light after having been turned just 180°. The gears added a significant build challenge for me, one that I am not sure I would have surpassed in the time allotted. Furthermore, my plans for installing this device required a lot of mounting into walls and onto doors, and as I don’t own my apartment I didn’t want to cause too much damage to my bathroom interior.

Alternative concept: I had purchased a crank flashlight to use as a replacement for my bathroom light as a backup plan. Instead of turning on the light in my bathroom, I intended to use the crank light from the time I received it to the due date of this assignment. 

The light I purchased: I ended up purchasing this very inexpensive light from Amazon. It had varied reviews; the flashlight also is supposed to do other things like power a radio and charge your cell phone, and people reported positively about the light but negatively in regard to its other features and long-term durability. I needed the light only for a short time, so I decided to go with it. 

Reasonable usage: Turns out, the crank flashlight worked really well! I could crank it for a minute or two and get bright enough light for 5-10 minutes of bright light before it started to dim (assuming I cranked it like crazy).

Day 1: I cranked this light a few minutes before hopping in the shower. It stayed on almost long enough but got really dim towards the end. I had to crank some more for teeth brushing. 

Day 2: Cranked the flashlight more today, kind of a pain before hopping in the shower early in the morning. Bright light for a flashlight, but rather creepy when used as a primary light in my super-dark, windowless bathroom.

Day 3: Breakthrough! Cranked the flashlight the night before while watching a show so this morning I would not have to crank it, I could just hop in the shower. This was a most excellent plan! Now if only I could remember to crank it randomly throughout the day it would make the experience a lot more convenient. 

Day 5: Still cranking the light night before, good plan. Instead of cranking again for teeth brushing I have cheated by opening the door to let natural light in. Brighter than flashlight and a lot less creepy. Also, easier to dry hair this way for sure. 

Conclusions: After over a week of using this flashlight, I am glad to be rid of it. It worked very well, and while it takes some planning to fit it into my morning routines it wasn’t that big of a deal. However, I’m glad to not have to continue using it because it was really eery in the bathroom with just this faint blue light (so eery, in fact, that I shot footage for a creepy video in my bathroom using the light from the crank flashlight, the concept of which I thought up while taking my regularly unnerving morning shower). Granted, the flashlight was reasonably bright for a flashlight, but 5 super bright LEDs can’t compare with three 60-watt lightbulbs. 

An interesting side note: I found myself listening to the radio a lot on my crank flashlight. I think I did this mostly because it was novel and I haven’t listened to the radio in ages, but still I really enjoyed cranking it up and turning it on when working or especially when cooking meals. 

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Renewable Energy with Industry Byproducts

This information has been compiled for a presentation and class reference.

Basics/Inspiration

A few weeks ago a friend of mine sent me a link to an article about an anaerobic digester that used waste water and leftover grain byproducts from the process of beer making to create methane gas, which can be used by the beer companies to power processes in their plant. The company that makes the digester and converts the byproducts into energy is Purpose Energy in Massachusetts. Magic Hat has partnered with Purpose Energy and is currently using their system.

From: http://www.salon.com/wires/image.html?image=140f36c0-09cb-43e5-92c3-2b684da54157@news.ap.org.jpg

How it works: Purpose Energy leases the space on which their digester is located. Magic Hat pays Purpose Energy to process their waste. Purpose Energy converts the waste into fuel (methane gas) which is sold to a Vermont power company, and is in turn sold back to Magic Hat.

System Advantages

Anaerobic digestion systems are initially expensive to implement, but like many green products it will save the company money in the long run. Not only does it create a small amount of renewable energy that the company can sell or use in their plant, but it also eliminates the need for waste removal (which is extremely expensive) and it lessens the burden on local waste systems (such as the waste water system). The business is also lessening the amount of greenhouse gases released into the atmosphere since they are catching the methane and carbon dioxide. For farmers, processing waste with a digester has the bonus of reducing odor around your farm, lessening harmful bacteria in their manure, and providing excellent fertilizer for their farm.

Anaerobic Digestion Process

Where are digesters used and what can they break down? Anaerobic systems are used in sewage and waste water systems. They can be used on farms to break down animal and plant waste. Anaerobic digesters can break down most organic compounds (even paper!), the exception to this general rule being wood.

The image below shows the general process of how a byproduct would be used throughout the digestion process.

http://www.skyrenewableenergy.com/renewable-energy/bio/

This is one example of how an anaerobic digester is constructed and functions. 

From: http://www.empoweringwind.co.uk/ad.htm

Finally, here is a diagram that shows the process of byproduct breakdown within the digester.

http://upload.wikimedia.org/wikipedia/commons/2/2b/Stages_of_anaerobic_digestion.JPG

Digesters can digest a single type of substrate or multiple substrates. They can also be single stage or two/multi state digesters, meaning that there are multiple digestion tanks that handle different steps of the digestion process.

The time to break down the substrate into all of its usable parts varies based on the kind of digester you have and what you are digesting, but generally will take 14-40 days (sometimes more, sometimes less).

Government Incentives

There are many available government incentives that can provide partial funding of a digester. Not only are there rebates available when you are using/implementing renewable energy, but there are also grants specifically from the USDA and state chapters of agricultural departments. 

In this article from BioCycle, the costs for an anaerobic digestion system were approximated at $1 million dollars. The farm received grants from the USDA and the Michigan Department of Agriculture that totaled $600,000. This leaves $400,000 that the farm needs to come up with on their own (in this instance the farm took out a mortgage). It’s no wonder that only about 2% of dairy farms use anaerobic digestion (according to this article written in late 2009).

With new incentives and financial assistance programs, hopefully the trend will lean towards anaerobic systems in the future. I personally would hope that common sense would also play a role in future decisions about sustainable opportunities on farms. Statistics in California from this article outline the scale of missed energy opportunities: currently only 1% of the manure in CA is being used to create energy. There are 5 digesters in the state, which generate .37MW of power; if California could harness their full energy potential, they could generate well over 105MW! Each cow per day could potentially generate 1.24 kWh of energy per day, and there are 1,420,000 cows in California.

Conclusions

If you read only one article on this topic, I would highly recommend this one written for the Green Economy Post by Chris de Morsella.

While anaerobic digesters don’t generate a huge amount of energy, they can provide enough power and heat for farms (and other companies that choose to use them!) so that they can maintain their operations independently. Furthermore, the benefits of anaerobic digestion are vast and go well beyond just renewable energy. Morsella summed it up best in saying:

Of course it is really really hard to sex up a song singing the praises of digesting manure, but it is a song… a message… that is important to get out there. A sustainable green economy will require us to become much better at how we handle our crap…. literally.

Reference Links:

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THEME BY PARTI