Thanks, Arefin. I did most of the design and SolidWorks work, as well as a bit of CNC machining for a few of the parts on the robot.
Although I really have to thank our team machinist (Gary Morin) and our team’s CNC sheet metal sponsor (R&D Precision) for turning around so many parts this year. Gary has been working almost non-stop at nearly every team meeting for the last four weeks fabricating parts on our lathe and mill (our school’s insurance policy unfortunately forbids students under 18 from operating the lathe or mill), while the students have been prototyping ideas and making all the non critical +/- 1/16" or +/- 1/8" parts and assembling the robots.
I like to draw inspiration from a variety of sources (including our past robots as well as those of other teams), and then meld it all together into a unique design of our own.
Another interesting bit of information about our 2009 robot: we only have six 1/4-20 screws on the entire robot*. Four are on the two pneumatic cylinders (because the rear pivot and clevis both use Ø.25 clearance hole), and two are on the trailer hitch. We used to almost exclusively use 1/4-20 due to it’s availability at Home Depot, however a #10/32 screw is about 58.3% of the weight of a 1/4-20 screw. (That adds up fast when using steel fasteners).
There’s a lot more interesting details, some visible in the render, some purposely suppressed, that will be released in due time. If you stop by our pit (at CTR or Championships), we’ll have a lot more information about the interesting features of the robot, although most likely I won’t be in the pits much due to event volunteering. Eventually I’ll also have the students post the CAD models and drawings on the team website.
Everything else is #10/32 socket cap head (most common) or button head, or #8/32 button head.
If you look at the full resolution (2560x1920) version of the render, you’ll see two 3/4" bore x 4.00" stroke cylinders.
As for their function, that’s up to you to figure out.
That is exactly what I was thinking. If you guys are able to control the speed of the shooting and angle I am sure you will be a force to be reckoned with at the comps. Nice job on the 3D design!
I’d have to disagree with that statement as most of the superstructure looks to be 1x1x.0625" square tube, which is insanely light. Plus he also said solidworks calculated 90lbs with out control system or compressor. So it really depends on how you define “heavy”
After just finishing several more renders, it appears I forgot to set some of the components in PhotoWorks, like the front chassis rail and the timing belt sprockets. Anyway, a different angle of the front of the robot.
P.S. Does anyone know a really good way to run real roller chain in SolidWorks (especially with different size sprockets)? I know you can do linear and circular patterns, but it’s just so much easier to make a belt-like loop and override the mass properties to the correct weight (25 pitch chain is .090 lbs/ft). I’ll switch to real chain if an easy way exists.
We did a weigh-in of the practice robot (which is a lot more complete than our competition robot, as we send the practice robot to the Suffield Scrimmage) with most of the control system mounted (including CRIO, PD Board, Side Car, 2 Jags and 4 Victors) and the pneumatics compressor and two accumulators. We also put an entire 4’x8’ sheet of polycarbonate to simulate the panels we have yet to cut out. We were missing some parts from the robot, but no more than about 10 pounds worth.
When we weighed in, we were at 99.5 pounds. Adding the other ten pounds of parts still to be installed, and we’re still ten under. And the mounting for everything weighs almost nothing, as we’re using 1/16" polycarbonate with 3/4" x 3/4" x 0.050"-wall aluminum angle with lots of rivets for making everything. Incredibly lightweight and strong.
This is just a beautiful model. Congratulations.
I won’t get a chance to see you in CT for I will be in Manchester, Atlanta and SolidWorks is a sponsor for Boston. Between FIRST, BOTS-IQ and others - I spend alot of weekends at Robot events.
I know you and your team will do well. Best wishes.
Marie
So we completed our practice robot this morning in time for the Suffield Scrimmage, and are working on completing our competition robot either tomorrow or on Monday. We’re making a minor design revision to our elevator which should be completed tomorrow*. And as soon as we have both robots fully completed, we’ll shoot some good photoshoot-style photos and I’ll post one of them up here on CD-Media.
But until then, a quick teaser from our practice robot. The competition robot has been painted/wirebrushed identical to the render, and is just waiting to be bolted together and wired/plumbed.
Yes, I know the foam on the front of the robot is being shredded. It’s getting replaced with black neoprene roughtop belting identical to the shooter tomorrow. The bumpers on our practice robot are also recycled from our 2007 robot, although the competition robot will use bright new orange bumpers. Also, our competition robot is going to use black pheumatic belting instead of the neon yellow given in the KoP.
When purchasing the stock for the rollers, I cheaped out and bought PETG instead of polycarbonate tube as originally intended, to save $80. And subsequently, it didn’t work as well as intended, so we didn’t really use it at the scrimmage today. Word of advice: if you have the money, just do it right the first time.
Don’t worry; no part of this robot ever extends beyond the bumper zone.
Actually, everything above the bumper zone is at least 3/8"-1/2" inside of the robot perimeter.