Category: Projects
2011
02.04

WEC 2011

Last weekend I had the privilege of attending the 2011 Western Engineering Competition (WEC) at the University of Sasketoon. The activities were a blast and the Senior Design competition was great. After presenting our design, we felt that we did really well. The other teams also did great jobs and I’m sure it was very tough for the judges to make their final decisions. Sadly, we did not win, but we had a great time competing and getting to know fellow students from across the country. We took some video of our robot/tractor and I have embedded them below.

WEC 2011 – It’s alive! from Benjamin Bergman on Vimeo.

This was the first time we had our robot running in it’s final configuration at WEC 2011 Senior Design.

WEC 2011 – Hay Bail Challenge from Benjamin Bergman on Vimeo.

In this challenge, we had to remotely control the robot to lift a “hay bail” (a marshmallow, in this case) and place it in a small cup. This was one of the easier challenges for the day.

WEC 2011 – Pasture Crossing Challenge from Benjamin Bergman on Vimeo.

In this challenge, we had to remote control our robot tractor and drive it across the “pasture” (represented here by a steep, ~40˚ slope covered in a plastic tarp and a layer of very soft dirt). We had to avoid hurting any livestock or the environment (ie. the trees). While it looks like we did quite poorly, everyone got about the same distance on this one.

WEC 2011 – Grain Sorting Challenge from Benjamin Bergman on Vimeo.

In this challenge, we had to separate the “wheat” (marbles) from the “chaff” (rice) using our robot. The robots built by most of the other teams used the vex panels themselves (they have lots of holes) to filter out the marbles, but this was slow and required agitation. Our robot used some rails on end that left gaps barely wide enough to catch the marbles and let the rice immediately fall to the ground.

WEC 2011 – Manure Moving Challenge from Benjamin Bergman on Vimeo.

In this challenge, we had to remotely control our robot to move a pile of “manure” (loose dirt) from it’s initial location across a line. Our performance in this challenge was not great as it was hard to maneuver our robot in the tight space, plus our scraping mechanism did not reach as low as we would have liked.

WEC 2011 – Barrel Race Challenge from Benjamin Bergman on Vimeo.

In this challenge we had to autonomously get our robot to navigate a figure 8 around a pair of “barrels” (pop cans) and then complete a lap of an oval track. The oval was no problem, and in our testing we could do it very quickly, but the preceding figure 8 in the soft dirt made it impossible to line up for the lap. None of the competitors were able to complete this challenge. Since it was worth 50% of our demonstration mark, that put a lot of weight on our presentation.

WEC 2011 – Barrel Race Lap Demo from Benjamin Bergman on Vimeo.

After the competition, we wanted to demonstrate our completion of a lap of the barrel race track, just for fun. Some other teams also demoed their lap code, but ours seemed to be the fastest.

WEC 2011 – Attempted Marshmallow Destruction from Benjamin Bergman on Vimeo.

During building, we found that our gripper arm had a lot of torque, so after competition we tried to cut a marshmallow in half. Sadly, the gears kept slipping since we had stressed out all of our mounts during competition, but we had fun anyway.

WEC 2011 – Attempted Pop Can Destruction from Benjamin Bergman on Vimeo.

After competition we tried to crush a pop, but our gears kept slipping as the mounts had been stressed during competition.

WEC 2011 – ROV from Benjamin Bergman on Vimeo.

After playing with our robot for a bit, we decided to attach a phone to the arm. This clip was just to get a “first person” clip, but we later set up an IP webcam server from a phone to remotely control it. It was a bit laggy, but tons of fun.

2011
01.25

As some of you are aware, I am a member of the University of Manitoba SAE (Society of Automotive Engineers) Formula Hybrid team. The major project that I have been working on for a while now is a CAN bus controller Arduino shield. The system is based on the one designed by Mike Sefton last year. We are using the same CAN interpreter because the manufacturer was generous enough to donate some chips to us. These chips work well, but they are designed to be used with an OBDII reader, so we are using a few work arounds to get the system to work for us the way we need.

Aside from some simple changes to the circuit, there are two major changes to the system. First, I added a the NUP2105L chip to the CAN bus to give us some over-voltage protection. The major cause of failure last year was over-voltage, which is always a concern when dealing with electric vehicles. The second change was to allow an outside system to communicate with the CAN controller over a serial connection. Last year the CAN devices were controlled directly by the Arduino, but this year the Arduino is basically a middle man that can do some processing of commands if needed.

For the hardware design, I decided to try out a few open source tools. I first tried KiCad because it was more cross platform and a fully integrated suite. There were some things I didn’t like about it though (although I may have just been looking in the wrong place for the feature I thought was missing) so I decided to try out gEDA. I personally liked the feel of gschem better than KiCad’s schematic editor, and the PCB software seemed quite good to me too. The workflow between tools is a bit less intuitive, requiring a few terminal commands, but I am quite comfortable with the command line, so I can see myself using gEDA much more in the future.

The files for the hardware design are posted here: HARDWARE

The firmware for the Arduino is posted here: FIRMWARE

The firmware is currently a very basic repeater but will likely see changes once we start figuring out what specific features we will need. Feel free to post a comment or send me an email if you have any questions about the design.

2011
01.14

Last term I took a course that involved a lot of FPGA programming. We used Altera’s DE2 development board as well as their example labs (Digital Logic and the first few Computer Organization labs). While the labs were quite enjoyable and very educational, it was a LOT of work compared to labs in other courses. This was also my first experience with Verilog (or any HDL for that matter) which didn’t help. Getting help with these labs was a bit tough as my classmates were all in the same boat, plus the professor and TA hadn’t done the labs yet. I have decided to post my solutions to these labs in case someone else down the line needs help with them too. I have included a README file with the code with a little more information and emails (or comments on this post) are welcome.

As an aside, I am currently hosting my code at github.com, but am debating switching to Gitorious (they seem to be more open source friendly) or possibly self hosting (Gitorious can be self hosted, or I might try cgit or Redmine). Does anyone have any thoughts on these? Perhaps other suggestions? I would love to self host, but the redundant offsite backups these services provide is always nice. Perhaps I will have to invest in a secondary, offsite server so I can do my own.

2011
01.10

New scope!

I just got my new oscilloscope in the mail today! Note to others who might buy this scope, it is a Rigol DS1052E that I got for Christmas and it was purchased from DealExtreme. Apparently they ship the Chinese version, so it came with the Chinese power cord and the menus were all in Chinese. Thankfully I had spare PC power cables I could use, and setting the menu language to English wasn’t too bad as the knobs and buttons are in English and the main menu had just enough English to get to the language select. One thing that DE did that was nice was they added a “gift” note to the box (for only $0.01 extra!) to save me from duty fees, I guess. Thanks DE!

I haven’t used it much yet, but the first photo might give a glimpse into one of my current projects.

(Also, sorry to the photographers out there for the poor lighting in these shots; I took them late at night and was a bit lazy in setting up lighting.)

2010
08.18

Weird circuit

So a couple days ago I was tearing apart a bunch of old computers I had kicking around, pretty much just a bunch of PIIs and older. I figure they aren’t really of much value used as originally intended, but I don’t want to see them end up in a land fill or piled up in someones backyard in India, so I’m stripping them down for components for electronics projects (if anyone needs any older computer parts (including CD-ROMs, floppy drives, power supplies, sound cards, CRT monitors, etc.) or components they suspect would be on an old motherboard, feel free to drop by).

Anyway, I pulled this one PCB out of the front of a computer that seemed a bit odd. All there is to it is a triple digit seven segment display, a single resistor (I suspect to regulate power to the display), and a huge amount of jumper pins. I think I count almost 100 pins. The thing faces out through the front of the computer case, I assume as a CPU frequency display (an older computer we used to have had a similar thing). What weirds me out is that I don’t recall there being any cable connected to this thing. I wasn’t really being too careful when disconnecting headers from the motherboards, but I really don’t recall ever unplugging this thing. Even if I had unplugged it, the majority of these pins look like they are just jumpers. There are two small 2×5 sections of pins that I suppose could have been headers for some other connector, but I don’t really see the necessity of all the jumpers.

Update: I have got the display powered up and played with the jumpers. Che out the new post.