Tag: marine sensors

Posted on

Reanalysis of the first results

Sunday 13th of October 2019

After 10 busy days full of working and adjusting our work, we finally managed to make the temperatures measured at the port presentable and in a good format.

After ten days of hard work the team (Zacharie, Katrijn, Sylvain, Wilfried, Medard and field expert Victor) finally have the confidence to test there sensors in the field

After reanalysing the data of 3 and 4 October and comparing them with the GPS shield output we can come up with the following results:

Results of the sensor left at the port of Cotonou

The conclusion of these measurements is that the system is too unstable to produce good results and the gps module uses a lot of battery. After removing the GPS module and stabilizing the system we found the following results:

The conclusion of these measurements is that the addition of shock absorbers  proved very beneficial, there was one power cut that happened during the recollection of the system. The results can be positioned in time in a reliable manner.

On monday, when we will analyse the results gathered during the weekend, we will see if these conclusions can be hold in a real experimental set up.

Posted on

Putting the system to the test

Friday, October 11th 2019

Report and pictures: Medard Honfo, Katrijn Baetens

After several days of preparation, a stable system was developed so we have the confidence to put the system to the test on the lake itself. After the last verifications our team (Zacharie Sohou, Katrijn Baetens, Medard Honfo, Sylvain Amoussou) and Mr Victor Okpeitcha,an oceanographic ingeneer of IRD/IRHOB took “une pirogue”, a local type of boat, to deposit three thermometers. The stations were next to existing stations of IRD/IRHOB, this will help the validation of our system and avoid double work.

Map of the positions were the sensors are released.
Station 1 (yellow) in the middle of the canal.
station 2 (orange) in the middle of the lake, this was not evident, luckily we got help from local fishermen
Station 3: A permanent station installed by IRD/IRHOB (blue)

Methodology used to install the sensors:

Step 1: fix a perforated pipe in the water

Step 2: Put the sensor inside, the sensor will float on the water

Step 3: close the system and put a lock on it

Fixing the sensors was not always straightforward
Posted on

Adding a shock absorber to the system

Tuesday the 8th of October 2019

Reporter: Médard Honfo

Pictures: Katrijn Baetens

Today we kept improving the system, we noticed the data gaps originated from small shocks that the batterie containers were not able to absorb, hence we searched for different methods to add a shock absorber to the system. The pictures show some of the ideas we had, in the end we kept it simple and just added some padding to the box. In the evening we put the box back to the port for a second test.

Investigating different methods for a shock absorber

 

 

 

 

 

 

Posted on

First data gave insights in how to improve the sensor

Monday 7th of October 2019

Report and figure: Sylvain Amoussou

Pictures: www.lastminuteengineers.com

We analyzed the data of the first prototype. The prototype has been activated at 5 pm on Friday, October 2019 as Wilfried described in the last report.
The figure shows the temperature measured by the prototype from 5 pm local time on Friday. The figure1 (a) shows that the temperature is almost constant from 5 pm to around 7 pm, the temperature decreases and oscillates overnight. The figure 1 (b) show the temperature from 12 am to 8am UTM time. The temperature still oscillated from 12 am to 5 am UTM. But after that, the temperature is almost constan, the oscillations started  when the sun went down and stopped when it went under.

Data gathered with the prototype during 3 October (a) and 4 October (b)at the port of Cotonou.

Today we also further improved our model:

  • The prototype has stopped for during the night, luckily it started back independently.
  • We verified the voltage on the batteries. We noticed that the remaining voltage was 6,28 V which is half of the 12V of the fully charged battery pack. We still need to further investigate if this is acceptable.
  • In the future we would like to use a gsm module in stead of a gps module, this will allow to transfer data without having to open the box. We found a solution to charge the lithion/ion battery that charges this module.
Electronic scheme from https://lastminuteengineers.com, a very helpfull site for developing arduino projects