In this workshop, participants could design their own soil moisture and water level sensors using rapid prototyping enabled by ink-jet printer with silver nano particle ink. As simple capacitive sensing is exploited for our moisture sensing, 2 conductive patterns separated by small gap can work as sensor electrodes. Therefore, there are various options on the electrodes design and potential that participants can come up with innovative ideas on the sensor design. During the workshop, participants sketched sensor patterns using PowerPoint and they printed them out on PET film using ink-jet printer. Then, they laminated the film for water proofing, cut its outline and put chip LED for moisture indication. Once the sensor film is ready, it will work as a moisture sensor by connecting to a measurement circuit that is used for a craft kit of soil moisture sensor “SenSprout”.

Unique and impressive designs are also important when we consider consumer version intended to be used by hobby farmers or gardeners, while currently available agricultural sensors mostly focus on toughness and ease of use. Thus, including consumer side people on the designing process through such workshop will be helpful to figure out attractive designs for possible users. In addition to that, some electrical engineers were joined to the workshop and they could give practical ideas on sensor design.

Through the workshop, all 17 participants could implement some sensor films and 13 participants could design their own patterns while the time was quite limited. There are several designs related with plant like plant pot, leaves and root which is also considered as the motif of original “SenSprout” sensor but designs that imply some company or product logos or animals were also proposed. These outcomes of the workshop should have interesting variety and inspiration on the soil moisture sensor design.

Since time is limited, it might be difficult to finish up all the implementation in time and there was no enough time to share and evaluate ideas each other. For further improvement, we would need to brush up the implementation processes to be accomplished more quickly and may need to ask participants some preliminary works.

The workshop was generally enjoyable for participants, gave impressive outputs and imply valuable aspects on sensor design. It would be interesting to iterate similar workshops with other participants.