With the growth of population, humans are facing a severe shortage of water resources. We need a more reliable monitoring method to deal with the increasing pollution. Nowadays, water quality monitoring of rivers mainly depends on manual monitoring. There are a few automatic monitoring stations but their construction and maintenance costs are high. We hope to achieve more intelligent river monitoring at a low cost.
Introducing Sardine, an IoT system based on a sensor network with many small wireless intelligent buoys (with low-power sensors), an unmanned port system (including an unmanned ship with sampling equipment and an unmanned port with ship charging and water sample conveying equipment), a set of water sample analysis equipment and a data center.
Intelligent buoys are widely arranged at critical position of the wate rway. The water quality indexes will be detected at certain times including temperature, pH, turbidity, TDS. The water quality data will be sent to the data center. When multiple neighbor sensors send a pollution alarm, the data center will send instructions to the port to send the unmanned ship to the contaminated area and then return with water samples for analysis. Analysis equipment will do the job.
The details of the whole system of Sardine are listed in detail below:
****Deployment point/Device principal structure****
The buoys are arranged according to《Technical Specifications Requirements for Monitoring of Surface Water and Waste Water》 (HJ/T 91-2002) and are maintained on the surface by anchoring. The outermost layer of the buoy uses a flexible waterproof material to wrap the lower perimeter to avoid damage from smash. The entire device uses plastic and plexiglass (for solar panel) to achieve complete closure to prevent any moisture from invading.
The buoy is equipped with a 2000mAh (3.7V/4.2V full) Lithium battery pack and flexible solar panels, in all directions, which can charge the battery in sunlight to ensure that it can keep working.
The frequency is once a day so the power consumption will be extremely small. In fact, the monitoring frequency has been greatly increased (manual: 12 times per year generally). When the battery is low (with minimal chance), the data center will send unmanned ships equipped with charging equipment to the designated buoy, fix it and wirelessly charge it to ensure that it can maintain operation.
All monitoring sensors and equipment are available for purchase, and we agree that the following sensors can be used in buoys:
Temperature and pressure Sensor using MS5541C, ±0.01C.
The pH electrode: E-201-C electrode of INESA, ±0.2.
Conductive electrode: DJS-10E.
Turbidity Sensor: TS turbidity Sensor.
GPS module: NEO-6M.
Solar charge and discharge Controller: AT89S52.
1A Lithium battery charging controller: TP5410.
Controller module and wireless communication module can choose OCROBOT Honeybee, which is an Arduino development board compatible with Italian production.
All above are low-power sensors/controllers, Because of the limitation of words we don’t tell in detail.
Each buoy is inserted into SIM card and uses 5G communication technology to convey information. When the buoy is not working, the buoy reports the status of the buoy battery and position once a minute, while in the working state, the buoy sends monitoring data to the data center after testing the water quality.
When the data obtained by the base station positioning exceeds the allowable error of the positioning, the GPS is turned on to accurately locate the buoy in order to retrieve the buoy.
When pollution occurs, the data center automatically sends unmanned ships to sample. The size of the unmanned ship is larger, the high-definition camera can be arranged to transmit the scene picture in real time when sailing, and it is convenient for the staff to judge the scene better. Of course, the transmission of video data also uses 5G technology. The electricity facilities of the unmanned ship and the analysis station are connected to the municipal power supply to ensure an adequate supply of electricity to the ship and the analysis station, which guarantees their reliable working status.
The analysis station will be built with all kinds of necessary instruments so that is can reach high accuracy like in labs.
All the data from all things will be sent to the data center so that it can independently instruct all the things without human orders. Of course, operator can directly control the ship but most of the time it’s not necessary.
Environment protection is always delayed action, but Sardine can help human to keep monitoring the environment so that we can realize what is happening to the environment on earth and evaluate the water environment better at lower cost. By establishing more accurate model, we can more accurately figure out the environmental capacity and the water self-purification capacity. Analyzing these data will help us to avoid excessive discharge and direct us how to deal with the relationship between industry and environment. The development of the economy will be “greener.”
Lucid waters and lush mountains are invaluable assets.