“We started with the idea of creating an interactive demo for fairs and it turned into one of the best side projects - the Bubblemaker!
We tried to create an engaging demo-game for events which should show the example of what you can build with our products. An interactive smart water meter demo with LwM2M and IPSO sensor (The Internet Protocol for Smart Objects) support. This simple solution for measuring the flow of liquids uses cellular or Wi-Fi connectivity to connect to the cloud and report the information on water usage or, in case of this demo, how much water was pumped through the system. Our demo also has options to measure the temperature, acidity, and pressure of the water.That’s why our Bubblemaker is based on the implementation of the Anjay LwM2M Client for Nordics devices.
Smart water meters are devices equipped with technology that goes beyond traditional water meters. These intelligent meters use mostly wireless communication and Internet of Things (IoT) capabilities to automatically collect and transmit water usage data to utility providers or homeowners.
The LwM2M (Lightweight Machine-to-Machine) protocol was designed to standardize messaging and device management for resource-constrained IoT devices. The LwM2M protocol optimizes bandwidth-efficient consumption by using space-efficient binary payloads and supports different wireless transport protocols such as NB-IoT, LTE-M, Wi-Fi, and SMS transport. It provides a uniform data format for easy interpretation of data, standardized device management processes, and support for FOTA (Firmware Over The Air).
Anjay is a library that implements the OMA Lightweight Machine-to-Machine protocol. Supporting multiple integration layers, it ensures the development of lightweight IoT devices.
Coiote IoT Device Management Platform allows you to manage your LwM2M devices throughout their entire lifecycle. Coiote IoT DM supports device onboarding, data management, data visualization, automated tests, firmware updates, monitoring & alerting, and cloud integrations.
Let’s Build
Our demo, as a game project, has options to change sensors and pump settings. It is possible to use a single water meter with an electrical or hand pump as well as two water meters with two hand pumps. This tutorial shows the usage of an nRF9160 DK with two water meters and one temperature sensor. Also, this demo has a variant where the water is pumped by an electrical pump. In addition, you can drive the electrical pump using CoioteDM!
NoteOnly the water flow meter sensor and the LED strip are needed parts. Other sensors can be excluded easily. For this go to the Add or exclude the sensors.
The bubblemaker supports the following LwM2M Objects:
- Security (/0)
- Server (/1)
- Device (/3)
- Connectivity Monitoring (/4)
- Firmware Update (/5)
- Sensors:
- Temperature (/3303) with multiple DS18B20 sensors on single 1Wire line
- Pressure (/3323)
- Acidity (/3326)
- On/Off switch (/3342)
- Push button (/3347)
- Water meter (/3424)
- Power Control (/3312)
We need to connect our sensors to the device. We have designed and manufactured the special PCB shield to wire everything up for easier connection of all required components. The actual PCB shield is designed for two temperature sensors, two water meter sensors, two acidity sensors, two pressure sensors, an LED strip, and a relay module for an electric water pump.”