I tried to understand "almighty" processors being used everywhere. From MP3 players to refrigerators and even coffee machines.Why do we love to complicate things? I agree with John E , who described a design similar to the one , that I published (with Bob Pease blessing) about 30 years ago in Popular Electronics. Hundreds of trackers are using it and it has only 4 photo resistors and simple differential-servo system.I had tons of positive feedbacks and never heard anything negative on it , except that some people did not understand how servo works and what kind of transistors to use on an output.Sixty phototransistors?Isn't it a bit of overshoot?It would be great for navigation , but to move solar panels we do not need such a sophistication.Just my humble opinion.....I always loved analog.
I built a a simple tracker in the mid-80's using 5 small, matched solar cells, voltage comparators and two shading strips. I forget how the motors were driven, just that it wasn't very pretty and it used dual battery packs. It worked really well, though.
I've also seen a cone shaped design which had 4 parallel holes with CdS cells at the bottom and a reference cell at the tip.
Have fun making the circuit and entering the program. I hope the focus of the device shifts to its multiplexing purpose. Everyone is focused on the solar application, but the sensors can be anything.
The program compares TWO banks (vertical and horizontal) of 30 analog sensors EACH. It uses one-byte precision or a maximum of 256 digital values. 256 divided by 30 sensors gives approximately 1 in 8 chance of two sensors having the same value. If you modify the PIC program to sense all 64 possible switches of the MUX into one pin of the MCU, you should consider right justifying the bits to get 10 bits of precision or 1024 values. This involves modifying the code at comments provided in the code. Contact me with any questions.
Yep, the analog quad cell / baffle arrangement worked well for detection but in a purely analog system, the servo motors were always being tickled. Digital lets you add hysteresis, averaging and any other sort of condition mediation you'd like. It's also stepper friendly. It works pretty well here in Hawai'i but I did much of my tracker work in Seattle, land of grey skies.
Everyone usually manages to settle on a solution that works for their situation ( cost, available parts, space, time, etc.. ) It's fun to learn from the diversity.
At 40-60K$ for a home PV system, I want to see every watt I can possibly get. I wonder if the contractor panels have to be marked" this side up"?
Nice work, Jerald. What I find interesting about your design is that it uses a solution that a human brain would use. No human would calculate the sun's position in order to find it quickly. Asking, "where's the sun?" should work for machines, too.
Truchard will be presented the award at the 2014 Golden Mousetrap Awards ceremony during the co-located events Pacific Design & Manufacturing, MD&M West, WestPack, PLASTEC West, Electronics West, ATX West, and AeroCon.
In a bid to boost the viability of lithium-based electric car batteries, a team at Lawrence Berkeley National Laboratory has developed a chemistry that could possibly double an EV’s driving range while cutting its battery cost in half.
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This discussion will examine what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.