Code Progress is Still Progress

It’s been a long time since I’ve updated, and to those following my project I apologize, I know how annoying it is to see an interesting project on the net stall for years. (well, at least I hope my project the info I’m putting is useful/interesting/inspiring to others)

Long story short, I left my old job last December, moved cities and started a new job in a different industry. Needless to say, life has been busy, and I haven’t had as much time for my projects as I’d like, which may or may not be a good thing depending how you view it. Moving 1,154 km away from my Dad’s basement workshop hasn’t helped either. No more driving to my parents place to do machine work in my spare time. I’m left to slowly acquire my own tools now.

I haven’t forgotten about the quadruped, and have even managed to get some work done on it. I’ve powered up the motor drivers and haven’t found any major design errors yet, which is a good sign. Motors are spinning, and potentiometers are being sensed properly. I still need to do a bit of work to tap the 0-80 holes to mount the angle sensors, and machine the drive shafts a little bit to engage said angle sensors properly, before I can get the PID controller working properly to move the joint to the appropriate angle.

I’m also considering moving to brass gears, at least on the motor. I’m not overly concerned about the Delrin gears stripping, as there shouldn’t be a massive loads on them that cause outright concern, but I am having trouble mounting them securely to the motor shafts. As it ends up, Delrin is a bit flexible, enough so that it won’t hold a set screw securely, and even with a set screw the motor shafts end up spinning inside the gear. Moving to a brass screw should solve this problem, and is likely the easiest solution, albeit a little bit expensive.

On that note, you may have noticed I’ve put up ads. For the longest time I’ve been against ads on my personal website, but web hosting and robotics as a hobby does cost money. I haven’t really settled on whether or not I’ll keep the ads yet…

Syndicated 2010-08-22 03:52:31 from Roko.ca » Robotics

A Blast From The Past (Sumo Style) Part I

It’s been a busy summer (and then winter), involving getting a new job and moving to a new city, so I haven’t had much time to work on my robots much recently, let alone update my blog! So, instead of posting any updates on my robots (those will come later on when I get more work done), I’ve dug up some information on one of my older Sumo Robots, aptly named:

Chomp!

Chomp! in Competition

Chomp! was my first sumo robot, and first robot beyond BEAM robotics. Built in my High School years, it competed for the first time in the 2000 Western Canadian Robot Games, and placed first in the 5kg Autonomous Sumo competition. Although slow and lumbering, this robot had a good (for the time) vision system and protective skirt system that deployed on startup.

The brains of the Sumo was the rustic Basic Stamp II, powering an L298 H-bridge that controlled 4 motors, one per wheel. An aluminum frame held the robot together, and a custom made decals gave the robot a nice fierce personality

Back before the days of commonly available Sharp IR Rangefinders, I used a solution involving Modulated IR sensors (40 kHz) and modulated IR LEDs. By toggling the LEDs on or off, from a single sensor I could determine if the robot was to the left, right or front of me. A far cry from ‘1.21 GW‘, my current mini sumo, but it worked, and helped get the robot first place!

Chomp! preparing for Battle, before deploying protective skirts

Chomp! went on to compete in the 200 WCRG for the next year or two, but other robots rapidly improved over the years, and Chomp! became too slow and the protective flaps too weak for stronger robots.

Chomp! actually had a sister (brother?) robot, named “Fatal Discharge”, which never ended up working right. Unfortunately, this was before I figured out enough about motor controllers to know that the L298 wasn’t quite up to the task.

After Chomp!, I went on to build “Event Horizon”, which was a moderately successful robot, and one of the first in Canada to have a vacuum system for increased traction. But more on that later…..

Syndicated 2010-06-04 02:40:53 from Roko.ca » Robotics

Quadrupeds Need a Whole Lot of Motor Controllers

It’s been a while since my last update on the Quadruped’s build progress, but I finally got my PCBs back for the motor controllers. Since the robot has twelve motors, I need six motor controllers in total (Each of my controllers controls two motors). They’re an updated version of the h-bridge I prototyped last fall, [...]

Syndicated 2009-06-05 04:35:02 from Roko.ca » Robotics

Some Random Stuff

One of my co workers working on a GPS project of his own managed to aquire some Sarantel Helical antennas, and got some for me as well. I’m planning on using them with the U-blox GPS module I have had sitting around. (I origionally bought the GSP module for a MUAV autopilot I’ve been slowly [...]

Syndicated 2009-05-09 16:45:44 from Roko.ca » Robotics

2009 Western Canadian Robot Games I

I spent the second half of last week scrambling to get my mini sumo robot, 1.21 Gw into a working condition for the robot games. I populated the circuit boards mentioned in an earlier post but as I grew low on time I decided to put those aside for this year. Instead of trying to [...]

Syndicated 2009-05-05 18:23:00 from Roko.ca