Each time I try building one of these things I get a little bit closer to achieving a solid heliostat design. This one still needs some improvements, but it does at least work well enough to try it out in the sun. I will post more on it in the near future, but, for now, here are some pictures to get the ball rolling.
Each of the 6 1ft^2 mirrors is adjustable. This way, the light can be focused on a smaller target. I originally planned on adding 12 mirrors total, but I decided to keep it at 6 for now while I try things out.
For now, I’m only shining the light through a medium sized window.
This picture doesn’t really show it, but the reflected light does a good job of lighting up the room. Standing in front of the light beam feels just like standing in front of the light from the sun.
This 12V, 2.5A power supply is used for powering the Sun Harvester Driver Board. More specifically, it is sized to work with the NEMA 17 Stepper Motors also sold in the store.
Since the majority of this store’s customers are outside the U.S., it makes sense to provide an international power supply. This is why multiple types of plugs are provided with the power supply. Simply choose the one that matches your outlet and you’re good to go.
After a LOT scheming, plotting, designing, assembling, testing, and documenting, two new circuit boards have finally been added to the ranks of the Sun Harvesting circuitry and are now available for purchase at the Cerebral Meltdown Store!
First up is the Sun Harvester Driver Board. There are of course many other driver boards to pick from, but this one is designed specifically for use with the Arduino Sun Harvesting System. You now have the option to make all of the connections to the driver board with an Ethernet input and screw terminals. This marks the first step in making the Arduino Sun Harvesting Circuit “soldering iron free”. (This is just for the driver board. For now at least, there is still some soldering required in other parts of the circuit.)
Next we have the Sun Harvester Shield Driver Board Breakout Board (Yes I know, I’m bad at naming things). This breakout board connects to the Sun Harvester Shield and makes it easy to attach multiple Sun Harvester Driver Boards to the circuit.
More information for both of the circuit boards can be found at their respective links. Keep in mind that I still have a bit of documenting left to do along with some proof reading. It will be a few days before I’ll be able to do much work on it again though, so hang tight!
OK guys, clearly I’m bad at naming things, but at least my titles are descriptive. The “PC based Arduino Sun Harvester Program Interface / Solar Radiation Data Analysis Program Update” is exactly what it sounds like, it’s an update to a PC based program that I put together about one year ago that is able to do two things, interface with the Arduino Sun Harvester Program and also help you figure out how much energy you can get from heliostats, stationary collectors, or dual axis sun trackers.
Over the last few months I have been quietly working on several different additions to the Open Sun Harvesting Project. This is just a quick preview as I still have a lot to do, but everything is rapidly coming together at the same time it seems.
The first addition that will be released in the coming weeks is the Sun Harvester Driver Board V1.0. This driver board is based on the Big Easy Driver by Brian Schmalz, but has been modified in several different ways to integrate more easily into the existing “Sun Harvester” circuitry. For example, two stepper motor drivers are assembled on just the one PCB, and an ethernet port has been added to make it more “plug and play”.
A breakout board has also designed to make it easy to add additional driver boards to the circuit. So if you want to add another machine, all you have to do is run another ethernet cable and two wires for power from the breakout board to the driver board.
Finally, if you are wondering what the silver thing with all the gears on it is, it is a nearly finished heliostat that I have been working on. This design has been in the works for nearly a year now. I’ve obviously tried construction other heliostats in the past, but none of them turned out very well. This was due in large part because I didn’t own adequate tools for the job. Over the last six months or so though I have invested in the equipment required to do it right. Of particular use is the CNC controlled plasma cutter that I added to the shop!
I do eventually want to have a full heliostat available for purchase from this website’s store, but that will still probably be quite a long way off. In particular, I still have to test this design, make jigs so that I can assemble it quickly, and also come up with the cash required to buy all of the parts required to make them in bulk.
Anyway, I still have lots to do, so I guess I had better get back to it!
The above video shows a group of students from Khalifa University, located in UAE, showcasing their very well thought out project consisting of a heliostat array design, collector, and control system. Even on this small scale, it is reported to be able to generate steam.
It was the video’s narrator, Fatima Adly, that originally contacting me asking for clarification on how different parts of the Arduino Sun Tracking / Heliostat Program worked. The same algorithm that calculates the sun’s position and heliostat angles is in fact incorporated into their program. They also added much more to the program such as wireless control via PC and tablet along with a backup tracking system.
I’m not sure what the breakdown of responsibilities were, but Fatima does seem to have done her fair share of the work. For example, there was more than one instance of her contacting me around 4:00am (her timezone) to try and work out one bug or another. When exactly she slept I do not know, but one thing that is clear is that she is a extremely hard worker!
The pdf and code files below were provided by Fatima.
I finally got around to making a video of the CNC machine I built over the winter. I have built a few different CNC machines in the past, but none of them were especially accurate. I took my time with this one though, and it actually turned out really well. Finally! I have a CNC that cuts out circles that actually look like circles!
It probably took about 100 hours to design and build this machine, so obviously I’m going to show it off now that it’s finished! I only have the video for now, but if people show enough interest I might do a full write up on it.
This heliostat was built by Josema of Spain. The machine itself is controlled by the Arduino Sun Harvesting Program featured here on Cerebral Meltdown.
You may have noticed that the mirror is mounted on top of a solar panel. This is because this heliostat also doubles as a sun tracker! Here is a quick video he made of it switching between heliostat and sun tracking mode.
Josema reports that the machine has great tracking accuracy due in large part to the worm gears he is using. These worm gears were originally used to move the power windows in cars. If you are interested in designing / building your own machine, this type of worm gear would be a great starting point.
This next picture shows Josema’s DIY electronics circuit wired together, which appears to be quite similar to the circuit used in the Arduino Sun Harvester Shield. Very Cool!
You can find more pictures of Josema’s heliostat on his blog. (The link should go to the Google translated version.)
You can also find his forum post on this site here.
The Stepper Power Control Boards which allow you to control multiple machines with the Sun Harvester Shield are now in stock! I only have 14 available right now, 8 without screw terminals, and 6 with screw terminals. It’s possible that they will sell out fairly fast since people will need to purchase one for every machine that they want to control. Thus they will most likely buy multiple boards at a time.
I will order and assemble more boards as soon as I’m able though, so hopefully they won’t be out for long when they do sell.
You can find out more about the Stepper Power Control Board without Terminals here,
and more about the Stepper Power Control Board with Terminals here.