As anyone who has been faced with a recently-manufactured household appliance that has broken will know, sometimes they can be surprisingly difficult to fix. In many cases it is not in the interests of manufacturers keen to sell more products to make a device that lasts significantly longer than its warranty period, to design it with dismantling or repairability in mind, or to make spare parts available to extend its life. As hardware hackers we do our best with home-made replacement components, hot glue, and cable ties, but all too often another appliance that should have plenty of life in it heads for the dump.
If you’re lucky enough to have a swimming pool, well, you may not feel all that lucky. Pools are great to have on a hot summer day, but keeping them crystal clear and pH-balanced is a deep dive into tedium. Sure, there are existing systems out there. They cost a kiddie pool of cash and are usually limited to particular pool parts. Existing DIY solutions are almost as bad, and so [segalion] is making waves with a dumb, brand-agnostic pool automation system called Raspipool.
Sensors for pH, ORP, and temperature are immersed in pool water flowing through a bypass pipe that runs between the filter and the pump. The basic plan is to control the pumps and sensors with a web-enabled Raspberry Pi, and have the Pi send action and threshold notifications straight to [segalion]’s poolside lounge chair. Each piece is dedicated to a single task, which allows for easy customization and future expansion.
[segalion] is trying to get more people involved so that Raspipool can keep really make a splash. Be sure to check out the project wiki and let him know if you can help or have suggestions.
Many of us have projects that end up spanning multiple years and multiple iterations, and gets revisited every time inspiration strikes and you’ve forgotten just how much work and frustration the previous round was. For [Daniel Riley] AKA [rctestflight] that project is a solar powered RC plane which to date spans 4 years, 4 versions and 13 videos. It is a treasure trove of information collected through hard experience, covering carbon fibre construction techniques, solar power management and the challenges of testing in the real world, among others.
Solar Plane V1 had a 9.5 ft / 2.9 m carbon fibre skeleton wing, covered with transparent film, with the fragile monocrystaline solar cells mounted inside the wing. V1 experienced multiple crashes which shattered all the solar cells, until [Daniel] discovered that the wing flexed under aileron input. It also did not have any form of solar charge control. V2 added a second wing spar to a slightly longer 9.83 ft / 3 m wing, which allowed for more solar cells.
Solar Plane V3 was upgraded to use a single hexagonal spar to save weight while still keeping stiff, and the solar cells were more durable and efficient. [Daniel] did a lot of testing to find an optimal solar charging set-up and found that using the solar array to charge the batteries directly in a well-balanced system actually works equally well or better than an MPPT charge controller.
V4 is a departure from the complicated carbon fibre design, and uses a simple foam board flying wing with a stepped KF airfoil instead. The craft is much smaller with only a 6 ft / 1.83 m wingspan. It performed exceptionally well, keeping the battery fully charged during the entire flight, which unfortunately ended in a crash after adjusting the autopilot. [Daniel] suspects the main reasons for the improved performance are higher quality solar panels and the fact that there is no longer film covering the cells.
We look forward to seeing where this project goes! Check out Solar Plane V4 after the break.