adrammelech
Posts: 2
Joined: Tue Apr 23, 2019 7:11 pm

Is the Raspberry Pi suitable for this project? (Solar Tracking a PTC)

Tue Apr 23, 2019 7:18 pm

Hello everyone.

I'm a fourth year mechanical engineer, and my grad project is going to be in something called a parabolic trough collector, the model we have doesn't include a solar tracker, so we're going to build one, and the solar tracking part is on me, (un)fortunately :D.

In the past few months I read a book on python (automate the boring stuff and dusty's object oriented programming in python), to get myself accustomed to the language, as I am really interested in webscraping, which python has a ton of modules on. I found out that the Raspberry Pi also operates on python, and the question is: can a solar tracker be done using the raspberry pi? with a motor and a sensor to track the best angle for maximum power. Or is the arduino best suited for such a task?

Thanks!

User avatar
Gavinmc42
Posts: 3927
Joined: Wed Aug 28, 2013 3:31 am

Re: Is the Raspberry Pi suitable for this project? (Solar Tracking a PTC)

Wed Apr 24, 2019 12:31 am

The Pi can do it, bit of an overkill unless you want to log data with it as well.
A parabolic trough would only need tracking in one axis?

A Pi and Arduino are both overkill, a simple analog tracker can be made without the need to code anything.
Google should find plenty of circuits.

My first use of Pi and Python was for solar panel and battery/power monitoring.
It uses a model A and is still working fine apart from corrupted SDs every few years.
I'm dancing on Rainbows.
Raspberries are not Apples or Oranges

adrammelech
Posts: 2
Joined: Tue Apr 23, 2019 7:11 pm

Re: Is the Raspberry Pi suitable for this project? (Solar Tracking a PTC)

Wed Apr 24, 2019 12:27 pm

Gavinmc42 wrote:
Wed Apr 24, 2019 12:31 am
The Pi can do it, bit of an overkill unless you want to log data with it as well.
A parabolic trough would only need tracking in one axis?

A Pi and Arduino are both overkill, a simple analog tracker can be made without the need to code anything.
Google should find plenty of circuits.

My first use of Pi and Python was for solar panel and battery/power monitoring.
It uses a model A and is still working fine apart from corrupted SDs every few years.
I've never thought of using an analog tracker circuit! How much knowledge do you need to understand those circuits though?

As for data logging, I'd like to data log values from the temperature sensors we'll use as well to learn more and showcase it to my prof, even though we have a commercial data logger (which I forgot its name).

thanks for confirming that the PI can do it!

User avatar
Gavinmc42
Posts: 3927
Joined: Wed Aug 28, 2013 3:31 am

Re: Is the Raspberry Pi suitable for this project? (Solar Tracking a PTC)

Thu Apr 25, 2019 1:52 am

I've never thought of using an analog tracker circuit! How much knowledge do you need to understand those circuits though?
You only need to know how to google the right words ;)
https://www.electroschematics.com/8019/ ... er-system/
Much simpler than trying to learn Python ;)

TMP112 and TMP75 are the i2c temperature sensors I use the most.
No problem with 5m cables on Pi's.
For solar PV panels I add an i2c isolator to protect the PI from ESD etc.
For these Pi's I use PiCore Linux, it runs from ram which is better for 24/7 apps

Most of my new stuff is done with Ultibo.
So not only can this be done with PI's I have done it three different ways.
Probably many other ways to do it too.
I'm dancing on Rainbows.
Raspberries are not Apples or Oranges

User avatar
omegaman477
Posts: 148
Joined: Tue Feb 28, 2017 1:13 pm
Location: Sydney, Australia

Re: Is the Raspberry Pi suitable for this project? (Solar Tracking a PTC)

Thu Apr 25, 2019 11:44 am

Although a Pi is somewhat overkill, having the underlying Linux O/S provides so many advantages (remote access, remote code maintenance, logging, watch dog applications,)

If this is a remote application, or highly experimental, consider an RPI.

Otherwise Arduino's will easily manage the task, and generally will provide far better power consumption (may or may not be an issue).

Personally being a Grad project I would use a Pi, and log the crap out of the rig, sense and record everything (position, times, solar levels, power/voltage/current levels, battery state, enviro, rig, system temperatures, night time events). Important to any Engineering (academic) project is not just if it works, but also the data you collected so you can plan how you will make system improvements etc. I worked as Eng Lecturer for some years and I always reinforced that with any project or experiment, expect it to fail, but plan how you will still show success with the data you collected, lessons you learnt. Engineers are paid to solve problems, not assemble kits. I have often granted top marks to failed projects due to their recovery plan and the lessons learnt, over projects that just switch on and work with no issues.

If your running long term logging, consider a USB stick for backup of the log data, in case of SD failure. Just a CRON job daily to copy all the log files onto the USB stick. Cant do that (easily) with an Arduino. Also consider an independant power source (own battery/UPS hat) for the RPI so it can keep logging during system wide failures, and manage its own clean shutdowns. This is a must with all solar powered projects. You want to know why it went down, not just that it did go down.
..the only thing worse than a stupid question is a question not asked.

User avatar
Gavinmc42
Posts: 3927
Joined: Wed Aug 28, 2013 3:31 am

Re: Is the Raspberry Pi suitable for this project? (Solar Tracking a PTC)

Fri Apr 26, 2019 2:44 am

Personally being a Grad project I would use a Pi, and log the crap out of the rig,
Yep, that's what I use Pi's for.
It is kind of cool ssh-ing into a Pi 100km away or the next building's roof and changing shell script on the fly :D

Once you get used to "Cron' it is so useful.
For shorter time frames "Watch" is good.
Try to avoid always running Python.
I'm dancing on Rainbows.
Raspberries are not Apples or Oranges

Return to “Automation, sensing and robotics”