Not only would you need so many, but I would also need it to only run once every two weeks since we are in a drought and have watering restrictions. I guess the idea of this article is not this product but to showcase an application to spark other ideas.
$299 for one sprinker head is very expensive. I would need at least 6 of these for my yard and I don't see myself spending that much. I wonder if they would be able to control costs by using a z-wave controller and the sprinkler as a plain z-wave device. The cost of the wifi, pi subsytems is likely to be the major part of the bom cost.
What are the engineering and design challenges in creating successful IoT devices? These devices are usually small, resource-constrained electronics designed to sense, collect, send, and/or interpret data. Some of the devices need to be smart enough to act upon data in real time, 24/7. Specifically the guests will discuss sensors, security, and lessons from IoT deployments.