Hi, I appreciate that many on this list are software oriented, but do we have any people with experience of measuring fluid parameters?
The WMT has an ongoing Project to improve the sustainability of water in the 'Model' River Allen. This follows the route of the real River through the Model Town and has, until now, been managed and maintained by volunteers and staff turning the mains water tap on and off. We have mapped out some requirements to do it automatically and a bit more sustainably by catching rainwater and pumping it in and out of the sump at the bottom of the river system. The current stage of development is that a bog garden has been established at the 'source' of the river to clean the water, but otherwise the rest is ongoing. (The Linux dimension will be fulfilled by the use of Raspberry Pi's for processing and control and for the web-based GUI.) We have plenty of ideas, but not a lot of practical experience at the moment. Our main problem is how to monitor the level of water in a number of places in the river system, eg in the water barrels that are storing the rainwater and (probably) in the sump. We would also like to measure flow through the river system at one or more places. Obviously we can use electro-mechanical means to do this (float sensors, paddle wheels attached to a pickup, etc), but we have been looking at various electronic methods, such as: https://www.efxkits.co.uk/liquid-level-sensor-and-types-of-level-sensors/ but commercial sensors tend to be expensive and although I reckon we could do the electronics for at least some of those, we have to keep everything dry. Has anyone ever done anything like this? Ideally, for level, an ultrasonic sensor with a good level of water resistance would be ideal (it won't be immersed, but it will be exposed to rain, mist etc). The capacitive sensor requires RF, which brings it's own issues and the other types may provide readings that are too coarse to monitor rate of change of level. I haven't found anything much yet that will give us flow measurement in a 'river'. The commercial types tend to be fairly cheap but designed to go into pipes. However, we should be able to come up with something using hall effect sensors, so I'm more interested in level at the moment. Any ideas, links to projects that have done this? -- Terry Coles -- Next meeting: Bournemouth, Tuesday, 2017-05-02 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR