Differences
This shows you the differences between two versions of the page.
Both sides previous revision Previous revision Next revision | Previous revision | ||
michka:research:microbial_fuel_cells:cardiff5 [2016-09-21 09:11] – michka | michka:research:microbial_fuel_cells:cardiff5 [2016-09-21 09:56] (current) – michka | ||
---|---|---|---|
Line 1: | Line 1: | ||
=====MFCitizen @Cardiff===== | =====MFCitizen @Cardiff===== | ||
- | **September 7th-9th, 2016** | + | **[[http:// |
- | **[[http:// | + | |
+ | {{: | ||
====Abstract==== | ====Abstract==== | ||
Line 51: | Line 52: | ||
===1.1 Getting mud for the Mudwatt=== | ===1.1 Getting mud for the Mudwatt=== | ||
+ | |||
+ | {{: | ||
We started the working session by walk to the seaside in Barry (Wales, UK), to collect: | We started the working session by walk to the seaside in Barry (Wales, UK), to collect: | ||
* a kind of clay slush | * a kind of clay slush | ||
+ | {{: | ||
+ | {{: | ||
* a more sandy slush | * a more sandy slush | ||
+ | {{: | ||
+ | {{: | ||
+ | |||
… to feed the Mudwatts that Paul got previously. | … to feed the Mudwatts that Paul got previously. | ||
Line 62: | Line 70: | ||
We filled the Mudwatts first thing when we arrived at the workshop, following [[https:// | We filled the Mudwatts first thing when we arrived at the workshop, following [[https:// | ||
+ | |||
+ | {{: | ||
+ | {{: | ||
We labeled them as follows: | We labeled them as follows: | ||
Line 67: | Line 78: | ||
* the sand-slush one was called **S** (for **“Sable”**) | * the sand-slush one was called **S** (for **“Sable”**) | ||
* the garden soil one was called **J** (for **“Jardin”**) | * the garden soil one was called **J** (for **“Jardin”**) | ||
+ | |||
+ | {{: | ||
===1.3 First performance measurements=== | ===1.3 First performance measurements=== | ||
Line 91: | Line 104: | ||
We decided to use our freshly prototyped PTS (the INA219 current sensor on an Arduino Uno, see section 3 for details) on the B Mudwatt to see how much power was coming from out there. | We decided to use our freshly prototyped PTS (the INA219 current sensor on an Arduino Uno, see section 3 for details) on the B Mudwatt to see how much power was coming from out there. | ||
+ | |||
+ | {{: | ||
Right after connexion, the load voltage was 1.03 V, and the current measured was around 10 mA, but decreasing very quickly. | Right after connexion, the load voltage was 1.03 V, and the current measured was around 10 mA, but decreasing very quickly. | ||
Line 165: | Line 180: | ||
* sometimes, templates come up in large .zip files with components from a manufacturer, | * sometimes, templates come up in large .zip files with components from a manufacturer, | ||
* open the template in Eagle, and check that it is the right one. | * open the template in Eagle, and check that it is the right one. | ||
+ | {{: | ||
* if you are using, as we did, a fiber-glass support with a copper layer on top, keep in mind that were you cut, you are removing the copper, and therefore the electrical connexion. | * if you are using, as we did, a fiber-glass support with a copper layer on top, keep in mind that were you cut, you are removing the copper, and therefore the electrical connexion. | ||
* export the G-code to Eagle’s plug-in connecting it to the CNC | * export the G-code to Eagle’s plug-in connecting it to the CNC | ||
+ | {{: | ||
* beware that the G-code is defined in the right unit - metric or imperial system. | * beware that the G-code is defined in the right unit - metric or imperial system. | ||
* make the CNC run | * make the CNC run | ||
+ | {{: | ||
* this part of the process is quite technical, as the dimensions there are challenging Paul’s CNC sensitivity. Paul had to try out several times, and play with : | * this part of the process is quite technical, as the dimensions there are challenging Paul’s CNC sensitivity. Paul had to try out several times, and play with : | ||
* the number of passes of the CNC on each cut | * the number of passes of the CNC on each cut | ||
Line 177: | Line 195: | ||
===2.4 Building Shantaram et al.’s PHS=== | ===2.4 Building Shantaram et al.’s PHS=== | ||
+ | |||
+ | {{: | ||
This was basically the same process as stated above, with a digression in updating Eagle to read the library files for the Maxim1797 layout, and getting compatibility issues with the CNC plug-in. | This was basically the same process as stated above, with a digression in updating Eagle to read the library files for the Maxim1797 layout, and getting compatibility issues with the CNC plug-in. | ||
Last but not least, soldering the small surface-mount Maxim1797 and its tiny leads to the chip was quite a challenge, which Paul has adressed with years of hand-made-machines crafting experience. He drops a spot of superglue below the chip to paste it to the PCB, and then solders each lead with a tiny soldering iron tip. | Last but not least, soldering the small surface-mount Maxim1797 and its tiny leads to the chip was quite a challenge, which Paul has adressed with years of hand-made-machines crafting experience. He drops a spot of superglue below the chip to paste it to the PCB, and then solders each lead with a tiny soldering iron tip. | ||
+ | |||
+ | {{: | ||
+ | {{: | ||
+ | {{: | ||
+ | {{: | ||
This being said, god bless through holes components ! | This being said, god bless through holes components ! | ||
Line 197: | Line 222: | ||
===2.5 Beam robotics “Solar engine” PHS=== | ===2.5 Beam robotics “Solar engine” PHS=== | ||
+ | |||
+ | {{: | ||
When discussing about a lower-tech charge pump circuit, Paul mentionned the Beam robotics circuits, which are often made of basic through-hole off-the-shelf components, and are powered by renewables. | When discussing about a lower-tech charge pump circuit, Paul mentionned the Beam robotics circuits, which are often made of basic through-hole off-the-shelf components, and are powered by renewables. | ||
Line 209: | Line 236: | ||
Anyway, we prototyped and tested the circuit (replacing the motor by a LED), and it worked perfectly well. A 2200 uF proved to be way to small to really see the circuit effect on a LED. We replaced it by a 10 F supercapacitor, | Anyway, we prototyped and tested the circuit (replacing the motor by a LED), and it worked perfectly well. A 2200 uF proved to be way to small to really see the circuit effect on a LED. We replaced it by a 10 F supercapacitor, | ||
+ | |||
+ | {{: | ||
===2.6 Through-hole-components-based charge pump=== | ===2.6 Through-hole-components-based charge pump=== | ||
Line 223: | Line 252: | ||
====2.7 Joule Thief PHS==== | ====2.7 Joule Thief PHS==== | ||
+ | |||
+ | {{: | ||
===2.7.1 Literature review=== | ===2.7.1 Literature review=== | ||
Line 276: | Line 307: | ||
==2.7.2 First prototype and next steps== | ==2.7.2 First prototype and next steps== | ||
+ | |||
+ | {{: | ||
While searching all the information mentionned above, we wanted to do a quick test with a basic JT design. | While searching all the information mentionned above, we wanted to do a quick test with a basic JT design. | ||
Line 312: | Line 345: | ||
====3. Performance Tracking System==== | ====3. Performance Tracking System==== | ||
+ | |||
+ | {{: | ||
===3.1 Why INA219 current sensor ?=== | ===3.1 Why INA219 current sensor ?=== | ||
Line 374: | Line 409: | ||
===4.1 Graphite electrode=== | ===4.1 Graphite electrode=== | ||
+ | |||
+ | {{: | ||
Paul built a graphite electrode of out graphite rods we bought at The Works, an Arts & Crafts shop. | Paul built a graphite electrode of out graphite rods we bought at The Works, an Arts & Crafts shop. | ||
+ | |||
+ | {{: | ||
He cut down the rods in smaller chunks, drilled them, and used an old bicycle stainless steel cable to assemble them like a collar. | He cut down the rods in smaller chunks, drilled them, and used an old bicycle stainless steel cable to assemble them like a collar. | ||
+ | |||
+ | {{: | ||
+ | {{: | ||
Then, he tightened them up with a second bit of bicycle staineless steel cable (a choice of material advised by Johann, from the Flower Power pot project). | Then, he tightened them up with a second bit of bicycle staineless steel cable (a choice of material advised by Johann, from the Flower Power pot project). | ||
+ | |||
+ | {{: | ||
A quick multimeter test showed that the overal resistance of the assembly was about 3 ohms. | A quick multimeter test showed that the overal resistance of the assembly was about 3 ohms. |