Journal

My documentation of the whole journey from start to finish:

Week 1

The final project is due within the next 4 weeks of our school curriculum and I have already prepped for the final project by purchasing the electronics 2 weeks before hand which all have arrived this week. My project's code and electronics will be based on an existing project done by a youtuber called Teaching Tech. This is his video: https://www.youtube.com/watch?v=VSH3wM5euVE&t
For This project there will be several sections of the build that will be considered to be the main modular set up. This consists of 1. Main body platform. 2.Housing of electrical components and receiver 3.suspension system.

Main body platform contents:

1. Sheet of laser cut out plywood.
2. Housing for 12v motors.

Housing of electrical components contents:

1. Arduino Uno
2. 14.8v 15000MAH Li-Po battery
3. 5v 12v power converter
4. RC Flysky FS-R6B recevier
5. Jumper cables and wires
6. Drive motor shield for Ardunio uno

Suspension system contents and control surface:

1. 3D printed road wheels, sprocket and tracks that use m3 screws as links.
2. Laser cut side panel for mounting suspension
3. Suspension system using rubber bands as springs
4. RC FlySky FS-CT6B remote controller

Equipments needed/used:

3D printer
solder iron
laser cutting machine
computer to speak to arduino

Designing the main body:

Before I had entered the course i had actually designed and modeled serveral of my tanks and therefore I thought I could use the research and development used for my final product as shown here.

As the days went and I started to buy and recevie the parts needed for this project I started to think perhaps my model might not fit all the components within a reasonable size just yet which is actually an issue which tank designers have been facing since the dawn of tanks till this very day. The designs now focuses on the practicality side of things like layout of components and technologies therefore I have proceded with that approach too by starting from the ground up by how the body and layout should be structured with a more "boxy" approach to simplify the design which has led me to make a cardbaord reference piece using scrap from the fablab.

And so I went on to design the new model using the cardboard piece as dimensional and layout reference and this time I will be making the detailed version with the outer most dimensions of the components translated into block/over simplified forms just without the rubber bands. Though I have started designing the tank in TinkerCAD which looks like this:

In the midst of modeling out all the parts, I had also used other people's designs taken from thingiverse. However, most would prove unusable in their raw state so I had to modify them to my needs using tinkercad. Their thing numbers are: 2456987 (tracks), 2414983 (running gear pre modded),3622109 (track tensioner pre modded)

*Note:this version is to help me visualise and understand what is needed for the last prototype.

Week 1.5

For the sake of production and print time, I have made a new print profile on cura for my ender 3 that focuses more on a fast functional print rather than something that took too long to produce and was not practical for its purpose in case any parts broke or needed to be changed. these are the profiles

Week 2

This week I had begun production and fabrication of the materials starting with suspension. the overall process took me 6 days to print out everything along with spare parts and just took me 1 hour to assemble everything, although I did have to remake and redesign some of the parts to allow for intermeshing to occur properly. In the end it was all well and good but one major issue was the back strut, it had constrained the rear suspension from moving or functioning properly and thus caused a sloped back on the tank.

I have decided to remove it and have improved the sloped back issue but it is still there but most likely due to the motors being too heavy and thus causing some slope otherwise it was fine.
However after assembling the whole thing, I noticed that the motor placements and the runnig gear were clashing with the main body of the tank that was laser cut. I tried to redesign a new motor mount/bracket around the main chasis

(left:old, right:new)

But decided to just invert the mounts onto the top side of the chasis to save time on development of a new mount and printing time which amounted to this:

After assembling the main body and all the mechanical components, I added in the electrical items which consists of the 1.5A 14.8v LiPo battery, BEC, Adruino uno and motor shield.

Week3

This week I have started on programming and getting the arduino to work with the RC set. However, I have met several challenges along the way.
I am follwing closely to "teaching tech"'s code provided and all seems to be going well. In his video he had adapted his code to have servos on his tank but here I have removed them as my tank is not intented to have servos but in the future if they are needed I can easily add them back.

Week 3.5

After wiring up and coding everything, I ran into several issues. Regarding the electronics of the tank mainly in the motor where by they wouldn't move and they would make a humming sound when given an input by the receiver. I had assumed it was the code and consulted many individuals with experience in arduino coding but to no avail.

Week 4:

When this week came about I had received help from a teacher and an intern to test out the motors on the Power Supply Units in school to determine if they were working or not, unfortunately after some testing they weren't working. as a result a teacher had allowed me to scavange for some continous stepper motors from previous builds and take them home to continue production/fabrication. As soon as I had gotten home, I went on to design a new motor bracket and added some leftover track links to accommodate for the extra space needed to mount the new motors as the previous bracket was just a bit too small.

Week 5:

Week 5 in fabricating this tank had been halted so that I may take the time to study for my upcoming exams. After my first exam I had taken a bit of time to continue working on my tank but came to the realisation that my RC transmitter and Li-Po battery had spoilt as the battery was puffed up and the transmitter was not lighting up as it should. What was made worse was the fact that my replacement transmitter had also spoilt due to my mistake of attaching 12v into it when it was supposed to take 5v. Following these unfortunate events my BEC broke at the contact point that outputs the 12v to the motorshield. This mean I couldn't power the 2 continuous stepper motors I had gotten from the teacher. Despite this I couldn't do anything about it as my exams started to come closer.

Week 6:

After my second exam, I had sought help from a hobbist shop that specialised in RC components to see what could be done. The people there had helped me revamp my whole electrical system. A new type of BEC was picked to replace old BEC. a new transmitter was issued along with a power distruber and a pair of 12v continous. To replace my battery they had also given me a Li-ion battery with a switch.

Week 7:

Once we had done all the electrical wiring it was time for the coding part. Admittedly i was not very fluent in it but was able to complete it with their help and now the tank runs like a charm. unfortunately we werent able to use the RC controller due to the receiver not being used here so we had to use a simple 2.4ghz controller with 4 push button inputs but was nontheless able to move the tank in all directions. A(backwards), B(forwards), C(left) and D(right).

Week 7.5:

I worked with the hobbyist shop one more time and it was to programm the tank itself. Personally i typed out everything but both i and the people there thought out the code until it worked.

This is the end result:

End

This brings me to the end of the journal of my Final EP1000 project. Currently the project is no where near complete and has much to be desired. Therefore i will be improving and constantly working the over all design to further perfect it and reach its goal as a universal testbed/platform for experiments. This project has indeed acted as an introductory bridge into the world of electronics and RC compnonents, next step would be to make something more complex like multi staged suspension controlled by singular buttons thus giving interesting geometry. As for things right now that could be changed, the suspension system could become more compact to allow for more effecient use and the inserts could also be changed to be more rigid.