Taking table tennis to a new level...

I recently received a table tennis robot from one of my friends. I am so excited and I can't wait to use it for the first time. Because of my tight schedule between classes and studying I don't have much time to work on my table tennis. And when I feel the need to practice there is no one around to play against.

In my residence there is not a lot of guys who like to work on their table tennis game, they usually just pitch for a match and play. So I will never be able to work on my technique with a partner because the way it usually works is, a lot of guys show up to play table tennis and than you have to start playing matches otherwise the waiting period is going to be too long for the players in line.

Now I have this wonderful machine that I'm borrowing this week, just for me. I will be able to work on my footwork and a variety of forehand and backhand strokes. The nice thing about the table tennis robot is that you can adjust the shooting frequency, the placement of the ball and the spin on the ball. All of the different settings are sent via remote, so you don't have to walk all the way to the robot to change the settings. You can even program this machine to shoot balls in a sequence making it possible for you to practice different drills.

Check out the website I created for our table tennis team: Huis Marais Table Tennis

Good News!!!

This week has been a very tough week but it ended up being one of my best weeks so far. I had a practical for three of my 5 modules and for each practical I had to do theoretical preparation. By far the hardest part of a practical is the theoretical preparation. If you end up doing your calculation and circuit design on the same day as the practical, then you are done for. I know that this is going to sound bad but that is what I did this week, I pretty much did my practical preparation on the day of practical. All of those days ended up being long and tiring. I had to do it because most of my time went into fixing and doing preparation for my E-Design demo that I had to do on Thursday. This was more important than all of my other practicals.

So for this weeks E-Design we had to create a remote for our previously built gate. The lecturer gave us two buttons, a Renesas G12 and a programmer to program the G12. They also gave us an infrared LED and a receiver which we had to connect to the G14, the main controller of the gate. Each of us were given a hexadecimal address for our specific remotes so that our remotes doesn't open other students gates.

We had to send information from our remote to the gate using Manchester coding. The information had to be sent in binary and had to be decoded at the gate. The three instructions that we had to send was open, close and stop. One button opened the gate and the other button closed the gate and if both buttons were pressed at the same time then the gate had to stop.

Building and coding the remote was quite easy but the most challenging part was to decode the information that was sent. So I sampled the information for decoding using a timer and an edge triggered pin. If the pin was triggered the timer had to start and only read information from the receiver at an interval of 889 micro seconds.

Everything worked fine at the end of the day and I managed to get all of my marks for the demo that day. This was my first successful demo, all the other demos had some sort of problem on the day of the demo.


The good news is that I now have a much better chance of passing this module which had me all negative and sleep deprived.  

Before I forget, I just want to mention that I took part in a table tennis tournament this weekend and I made it all the way to the semi-final. I must say, best week so far.

E-Design... making my life horrible!!!

I had a tough couple of months and it's only the beginning of the year. This term hasn't been going good at all. I am in my third year of study, electrical and electronic engineering, and I am starting to feel how it is getting a bit tougher but at the same time as though the work hasn't changed. It's a weird feeling and I don't know how to explain it.

This year we have a module called E-Design which we'll have in both semesters. E-Design is a practical module where we have to design and build an electronically operated gate. We were given a basic PCB with a specific layout, Renesas RL78-G14, LCD screen and number of other components needed to design and build the gate.

Our first task was to build a 5V power supply, it wasn't that hard to build because we were given about 12V from a DC power supply and we had to use a voltage regulated circuit to step the 12V down to 5V. After finishing the power supply we had to connect the RL78 to an external UART and then we connected the RL78 to the LCD screen and display a message on the LCD screen showing the current operating mode, test or normal mode. For know nothing has to happen in normal mode except for switching into test mode and displaying a welcome message .

The whole setup gets connected to a computer for testing via the external UART. Different commands are then sent to the RL78. When in test mode characters received that are not commands must be stored in a buffer. The contents of the buffer has to be displayed when the display command gets received. There are commands for opening and closing the gate, reading the current of the DC geared motor and switching the buzzer on and off. There is also a check status command which receives the status of the gate, opened or closed.

For this module we have 4 demos that we have to do, the 4th demo will be the final product, we have tests that we write on specific parts of the project that we had finished and then finally a report that we have to write. The requirements for passing the module is maintaining an average of 50% in all the different assessments. So that is not good news for me because, believe it or not, I failed the first two demos and the first test. Things aren't looking to good for this module but I believe that I can still pass this module. One of my goals while doing my undergrad is not to repeat a module.

So I failed my first 2 demos not because I could not do the work but because I had some bad luck when I had to go and demo my project, The first time my PCB was faulty and while trying to solve that problem I managed blow up my RL78 board and I had to buy a new one. I was allowed to demo the following week but only for half of the marks.

The second time wasn't very different than the first time, one of my my friends who already went to demo his project told me that the lecturer didn't have a problem with the pin of the gate popping out and that the lecturer didn't subtract any marks for that. I thought that I was also going to get full marks for that section, so I went to demo my gate. Before the demo I told the lecturer that the pin pops out and he told me that it was fine and that the pin on his gate also pops out. Feeling confident, that I was going to get all of my marks, we continued with the demo.

When we tested if the gate opened and closed the pin popped out, still chilled and calm. because the lecturer said it was fine And then all of a sudden the lecturer said that it is going to be a problem and that he has to subtract marks. Now I was stressed because I told him before hand about the pin and he didn't have a problem with it and the same thing happened to my friend and he received  all of his marks when his pin popped out. Keep in mind that at this point in time my DC motor could rotate clock - and counter clockwise.

I told the lecturer that I was actually hoping to get all of my marks for that section, it was 5 marks out of the the total that was 12 marks, and he just looked at me and said that that is how it is and if I wanted to I could go and fix it and come back and demo my project again. At this point I was thinking to myself, do you really want to lose 3 out of the 5 marks because a pin popped out... just go fix it and come back... So that is what I did. Keep in mind that there was no need to solder or program anything I just had to take the wire and bend it into a shape so that it would not pop out if the gate closed or opened.

Finishing up the gate I decided to give it a test run... I could not believe my eyes for what I'd seen, all of a sudden my DC motor wasn't rotating in any direction. The DC motor could rotate but not with the control of my RL78 board but by connecting an external power supply to the motor. Now instead of only losing 3 marks for this section I was going to lose 5 marks, and that because of a stupid pin. And that is how I managed to fail my second demo as well, dumb luck!

There are still two more demos left and I have to ace both of them if I want to pass this module, I believe that the tests aren't such a big problem because I can just study for them.