pic: 4587-Sheet Metal Chassis V.2

[Greg Woelki]

Originally Posted by AustinSchuh

Big squares save even more weight for less machining cost.

This frame is quite beefy but keep in mind that the sharper the corners the higher the stress concentrations.

[Cash4587]

Originally Posted by Greg Woelki

This frame is quite beefy but keep in mind that the sharper the corners the higher the stress concentrations.

I've actually changed majority of the lightening holes to parallelograms. They look nicer to me, and I have used a pretty big fillet on all the corners (3/16 radius)I have not however put any Swiss cheese effect on the drive rails yet. They are not finalized, neither is the belly pan.
Seen here:
http://prntscr.com/40gv2q

[Greg Woelki]

Originally Posted by Cash4587

I've actually changed majority of the lightening holes to parallelograms. They look nicer to me, and I have used a pretty big fillet on all the corners (3/16 radius)I have not however put any Swiss cheese effect on the drive rails yet. They are not finalized, neither is the belly pan.
Seen here:
http://prntscr.com/40gv2q

It is probably still strong enough, but taking out the same amount of material that way instead of with circles makes it significantly weaker.

[Cash4587]

Originally Posted by Greg Woelki

It is probably still strong enough, but taking out the same amount of material that way instead of with circles makes it significantly weaker.

I think It will be okay.. But then again IDK because really, I am just a student. I have only put in about 15 months of solid works use on and off. However, 148 uses a similar pattern on their drive train:

https://www.flickr.com/photos/robowr...7642758521834/

[AdamHeard]

Originally Posted by Greg Woelki

It is probably still strong enough, but taking out the same amount of material that way instead of with circles makes it significantly weaker.

Eh? I don't agree with this statement.

Triangular pocketing is far more optimal (unless too much is taken out) than circular. If an equal amount of weight is removed the triangular pattern is stronger unless it's laid out awful.

[AustinSchuh]

Nice! Looks like a solid design, and like you got all the tricky bits right.

I'd put some material back in the front and back of the frame. Those parts take a beating... You can drop some of the material on the top of the frame, and on the rails holding the wheels. The frame itself will be strong enough, and the holes make it easy to inspect your robot for wear. Point impact loads from other robots and field elements should be your biggest loads. You can take the inner frame rails down to 060 as well. Reinforce the bearing holes when you do that.

Consider lightening the belly pan, and adding PEM nuts in for your electronics. Those small touches take a design to the next level.

[Cash4587]

Originally Posted by AustinSchuh

Nice! Looks like a solid design, and like you got all the tricky bits right.

I'd put some material back in the front and back of the frame. Those parts take a beating... You can drop some of the material on the top of the frame, and on the rails holding the wheels. The frame itself will be strong enough, and the holes make it easy to inspect your robot for wear. Point impact loads from other robots and field elements should be your biggest loads. You can take the inner frame rails down to 060 as well. Reinforce the bearing holes when you do that.

Consider lightening the belly pan, and adding PEM nuts in for your electronics. Those small touches take a design to the next level.

I'm interested in using PEM nuts now for a specific feature on the chassis. Could you provide more information or an old thread that gives more info on these?

[roystur44]

Originally Posted by Cash4587

I'm interested in using PEM nuts now for a specific feature on the chassis. Could you provide more information or an old thread that gives more info on these?

I've included links of what I think would be the most typical type of pem products you would use in a robot assembly. All these are self clinching press in hardware. Standardized on a thread type. 1032 would be a good thread size.

FHS Press in studs
CLS Press in nuts
SO Threaded standoff
LAC Floating self locking threaded insert
PL Nylon Locking nut
F Flush nut

Prototype Kit

[Cash4587]

Originally Posted by Joe G.

Do you have plans to make use of the rather large dead space within the space created by the beveled sides? If this area was a little more open, it would seem to be an ideal location to tuck some electrical and pneumatic components.

I really like the one piece sheet metal battery mount design.

I haven't really thought about it yet. I am not sure it it would be ideal due to the fact that I would have to cross over the drive components to get over to that space. Another thing is I think next year we will have more space for electronics due to our new roboRIO. If needed SOMETHING, I don't know what, will go in there. There are some decent sized access holes on the bottom.