pic: Inventor Fun

There ain’t nothing to this CAD stuff

Looks good… Might we see a different view to this? maybe an iso, or a side view?

More shots Here
Check it out.

Lat’s just hope that there aren’t steps in '06, or any type of somewhat steep incline for that matter. It doesn’t look like you have enough ground clearance to climb anyhting. But straying away from the negatives, it looks like a pretty solid design, good work… Could you let us in on speeds you calculated/are expecting from the drive base? Also, where would your overall base weight come in at?


Speed is 6.5 FPS
Weight as shown is 70 Lbs.

Rod i am always impressed by your designs, how you always have such detail in your designs. I was wondering if you had considered going with a 2 speed tranny to make your drive base a little more versatile. i figure it will add at most 10 lbs and if you gear it so it gives you 11-12 fps i think you will have a very solid competitive chassis. And with the way i calculate things that is still in my “half base, half manipulator” rule.

I like the way you think Greg, 229 ran a 2 speed transmission this year (13fps and 6fps) and it was extremely useful for blitzing the opposing alliances home row. Is the center wheel lowered or is this a flat 6? Awesome design once again. I can’t wait to see what you add to the top! :slight_smile:


Wow, you already know what the 06 game is?!

I must have missed the memo. :rolleyes:

We would like to prototype a few 2 speed trannys first. We as a team are not convinced that a 2 speed gives you that much advantage (We have been wrong before). It would be fun to do when we get a year round build location.
Center wheel is 1/8" lower.


I like the way you think, I like the way you filleted the cutout in the bottom plate. I remember an earlier version where the cutout had sharp corners. Maybe you are cutting to much out of the bottom plate. Perhaps a different cutout design that has smaller triangles but more of them. I am not sure I like the idea of using the motor mount as the rear bumper, but I like all the room up front for the arm/manipulator. I like how it all fits into a nice neat package, but is still easy to get to everything. Overall, I think the good points way outnumber the bad. I think that you might have to much time on your hands.


i think this is a pretty cool design; i like the use of the rods as structural members. what material thickness are you using, and why’d you choose to go with this option?

also, i notice that the rods on the sides don’t run the length of the chassis, and i’m not sure how thick the base plate is; are there any concerns about the frame flexing (especially in the center)? or are you counting on support from the added superstructure that’ll (probably) come with an end effect?

I remember seeing something very similar to this before. I know you can make a good argument for the weight of this setup (forces a lighter arm and a lower CG) but I think 70lbs is pretty heavy for what you’ve got going on there.

Also, unless I’m looking at it wrong, it seems like those rods could get bent into the wheels causing a jam.

Anyway, keep up the nice work! :slight_smile:

The rods are 3/8" Stainless Steel. The base plate is 1/4" Alum. The superstructure will add some support. I chose to use rods to get away from the “Box”, and try something new.

Very nice example of how powerful Inventor can be. Great job!

Very nice! I would love to be able to do that but lack the patientce (not to mention time) to do such a nice job in inventer.

Nice utilization of the rotery encoders and protecting them because i know my team has destroyed 1 too many because of lack of planning and protection.

Very nice job indeed, I have lots of comments now, heres a few:

-Why did you go with the 3 bar frame on the outside? Its innovative but I’m not so sure how productive

-Very Nice use of the encoder, could you tell us more about that?

-Based on the First’s history of changing size requirements every year, you may want to investigate another place to mount the battery, plus it looks a little tight there, changing it might be a pain if you don’t have much room to work with. This might also apply to the wiring too, its a bit tight.

-I got more, but for now that looks great. Good job.

Looks like a very open design - lots of room to move things around or make changes.

I vote for the 2-speed tranny. That was one of the keys to 103’s success in 2005 - it was geared for about 6 fps and 14 fps (which was great for banzai runs to the opposing home row!).

Did you couple the speed encoders to the axle with flex couplings? If not, I strongly recommend you do - the Greyhill encoders don’t take kindly to side loads on their shaft bushings, plus it’s just good engineering practice. That way you don’t have to be quite so precise with the axial alignment.

Nice Inventor work, too!