Our relationship in the food sector plans to measure liquid levels and report on line at hundreds of locations in Europe using ultrasonic sensors and with a modest budget. Wifi as a connection method was excluded so we practically had to limit ourselves to NB-IoT, Sigfox or LoRa. Based on this customer demand we conducted market research on Make or Buy possibilities of a necessary IIoT Gateway. We started from a device based on a standard industrial Raspberry Pi architecture and/or motherboard.
The general requirements were as follows:
- Wide-ranging deployability and future expansion possibilities
- Think of switching functions (LED lighting on sensor device, warning signals, etc.) in addition to sensors and/or a (touch)screen for local operation/feedback.
- For this we use Node-RED as IoT wiring software.
- Possibility for local printing of information on a printer device
- Robustness of electronics in (rough) practical conditions of the food sector
- Availability and sufficient support for a certain period of 5 years.
The more specific technical requirements relate to
- Interfacing with at least RS485
- Connection of a display (optional touch)
- Choice of LPWAN interfaces
- Support of Ubuntu Snaps
This market investigation ultimately showed that in this case the best choice can be made by:
- Create your own IIoT Gateway using an existing ARM / RPI motherboard.
- Develop additional LPWAN modules or combinations (e.g. existing semi-finished products) in order to have freedom of choice in the LPWAN techniques NB-IoT, Sigfox or LoRa.
- In view of the budget, a Pycom FiPy module has been looked at for the last time as a semi-finished product.