New design

One of the primary goals of this project was simplicity and low manufacturing cost, with previous design that goal was hard to achieve, so we changed the design, or rather architecture of the system.  In the diagram bellow you can see new system design, the goal here is to reduce total parts count per plant and also reduce total price per plant, so the first thing to do is to dumb down individual Plant pod device. The plant pod device still has sensors for temperature, humidity and barometric pressure, light intensity and specter sensor, low liquid level sensor and piezo transducer. We removed LCD display per plant, moved it to the Plant pod hub and added simple single addressable LED indicator per device. The plant pod hub device now has multiple liquid connections, inputs and outputs, device collects nutrients and water from the system infrastructure, mixes it in corresponding ratio (Per plant) and dispatch it to the Plant pod device, which now has only one liquid connection. This approach allows  us to have independent Plant pod device, that you can take with you. For example, imagen roof top garden that you can visit and take the plants you want with you and then place them in the kitchen, ready for usage when you need them. In your kitchen you would only need to supply power for the operation of the piezo transducer (Aeroponic mode). The Plant pod hub now uses two peristaltic pumps instead of the individual electromagnetic valves, removing the need for pressurized system infrastructure.

After completing these two main parts of the system (Plant pod and hub) we will continue to develop other parts of the system (Infrastructure, environment control, etc.).

Proof of concept

Here are some side projects developed as a tools for POC for the Plant pod project:

Time lapse camera

Using ESP32 CAM board, this allows us to document plants progress during tests. ESP sends pictures directly to Azure blob storage.

Plant growing module (Space PVC pipe)

These are some PVC pipes used to hold the test plants, we used Al. foil and kepton tape to prevent light ingress to the root area. One will be configured in aeroponic mode, using piezo transducer and the other one will be in hydroponic mode, using air pump to supply oxigen to the plants root system.

The plant pod device V3

Here is some rendering of the work in progress V3 Plant pod device

This is the bottom part of the device, it will also have top part that is connected to it using pogo pins and magnets. Bottom of the device will have electrical and liquid connections with twist on/off action for attaching it and removing from the system. We also included some thermal insulation layer between inner and outer shells of the device itself, to enable lower energy consumption in extremely hot or cold environments.