Extra update: A Night Before The Exhibition!

EXTRA UPDATE: A NIGHT BEFORE THE EXHIBITION!

Hiiii guysss!!!  💙💙💙

Tomorrow is the day of exhibition !!! 

Are you exciteeeeeeeeeeeed yet!!!??? 😆😆😆😆

Because we are already hyped enough over here! 😁

Hmmm....what to do a night before the exhibition??

First of all, of course its makan time!! 😋😋😋😋
Thanks to our member Qyla for bringing back foods from her hometown to serve our starving stomach while preparing for the very last stage on our project!

Wew!! Chicken, beef, fish, karipap and SAMBALLL!!!! 😋😋😋

Now that we have filled our stomach and its time for seriousness. As from last week, the mechanical part is not fully solved yet, we still haven't figure out a way to let the DVD mechanical part stand and how to let the motor gently connect to the gear. But for now, everything is solved by doing some mechanical build up work, we managed to come out with a stand that are able to stand firmly. Also, the motor can now connect to the gear wheel and there is also a long and stable stage for us to place our specimen! yeayy!!!

Mechanical look of the lever.

Also, following from week 7, we faced a problem where the current supplied to the motor is not high enough, causing the motor to be not able to spin. We need to give it a manual push for it to spin and to move out the gear. The good thing is that, we bought a lithium ion 18650 and an AA battery and that solved our problem!

The reason we are using 18650 and AA cell is because 18650 provide voltage of 3.7V and AA cell provide 1.5V (total of 5.2V) which are still able for the motor and IC/motor driver to hold and function. If we were to use two 18650 cell, that will be a total of 7.4V and the motor together with the IC might burn out anytime because the maximum input voltage for L293D is 7V and for motor DC is 6V. We connect the 18650 and AA cell in series and they managed to give the motor enough current to spin without the need to give it a manual push in order to initiate spin.

Lithium ion 19650 and AA cell connected in series

The exact way to do this is to connect the IC pin 8 to positive terminal of the lithium ion, and the negative terminal of the AA cell is connected to the breadboard ground. the positive terminal of the AA cell is connected to the negative terminal of the lithium ion cell. A battery holder is strongly recommended to be used in this case to provide a stable connection between the batteries and the cables. By doing this, our motor now have enough power to move and yet it is not over voltage! (yeayyyy woohoo!)

Now that the lever can move up and down without the need to give it a manual push to start the spinning motion.

Upper view of the robotic lever

After the hard work of 7 weeks, our microscope with a robotic lever is now fully ready to see you all and perform at its best tomorrow! 😉😉

See you there guys! 😃😃

Event Details

Kuala Lumpur Engineering Science Fair (KLESF) 2017

(Booth C34 & C35)
The Mines Exhibition Centre

9am - 6pm

Polarizing Microscope Using Smartphone

XOXO 💘,

Team Sotong