276-2045 Advanced Mechanics & Motion Kit

Advanced Mechanics & Motion Kit - P/N: 276-2045 - $24.99 USD - $25.99 CDN

The Advanced Mechanics & Motion Kit is now available and contains a number of components to help students learn about different mechanism types and about the mechanics of motion.

While we expect many of the VEX Robotics Competition participants will be excited to use these mechanisms on their VRC robots, this kit was developed for in-classroom efforts.

For more information on the kit, refer to the product page:

These look really awesome. We’ll be sure to order a set soon.

I can’t see many of those being useful in competition, but it’s definitely a great tool that teams can use to learn new things, especially teams that are just starting out. Good job again VEX! :slight_smile:

Will you be selling the parts individually such as the universal joint?

Outstanding! This is a very nice looking kit, and I’ll definitely pick up a set or two for classroom demos/experiments.

I do hope some of these parts will find their way into other SKUs; particularly the U-joints which I think will be very handy for a variety of uses.

Also, the reinforced worm wheels are a welcome addition and would be great if they found their way into the Advanced Gear Kit.

Now just add a ring gear suitable for making a planetary gearbox and you’ll have all the major mechanisms covered!


  • Dean

Eventually… maybe… probably. :slight_smile:
We know people will want to see some of these in individual packs, so I imagine we will do this. Nothing is happening at the current time. I’ll wait to get some more product feedback, first.

Hi Dean,
The reinforced worm wheels were rolled out a few months ago in the Advanced Gear kit. :slight_smile:

Planetary gear… it’s on the list, we’ll get there eventually.


Outstanding - I haven’t purchased that kit in a while, and it looks like the picture still shows the old design. I’m glad to hear these have rolled out to completely replace the old 24t worm wheel.

Thats great to hear. It is always fun to see what you guys come up with. I’ve been very impressed with the functionality and versatility of the latest round of new products (turntables, new linear slides, VEXpro, IMEs, this motion kit, etc). Keep 'em coming!


  • Dean

Lead screws, cams, new sized bevel gears, I swear if you guys release any more awesome kits this year I’m going to run out of money for food:D

P.s. How how many threads per inch on the lead screws?

Yay!!! New toys! I am glad to have stonger worm wheels. During Round-Up I had issues with worm wheels snapping in half and shooting across the room. I advocate safety glasses because of that experiance. Back to new products, how strong are the hand cranks, would they be strong enough for counter-balanceing with rubber bands? Final question, is there any grove or similar thing that fit the cam and the cam follower togther or do they just have to be maticulusly lined up? Thanks, looking forward to using these new products.

My Adv Mech kit arrived today.

Anyone used the lead screw to lift an arm yet?
Looks like it would be great for a low backdrive lift system.

Looks like another great addition to the vex system. This has been a good year as far as new parts go. :slight_smile:

My Advanced Mechanics & Motion Kit just showed up today, and I thought I’d post a few details and my initial impressions for folks that don’t have them yet.

These have set screws on both ends, which are needed for stability of the joint. They appear to be good up to about 45° off-axis. They seem fairly strong, though they do have a bit of play. If you need to transfer power through a variable-angle joint, these are the way to go. Even for fixed-angle joints, these will be simpler and possibly lighter than using bevel gears.

Lead Screw
Each segment is about 1.175" long with 6 turns. That makes the pitch about 0.196"; about 0.2" of travel per turn. At this pitch, it appears to be very hard to back-drive, so holding a position under load might not need an active control loop.

You loose one turn in the nut, so the maximum travel will be about 1.175" x segments - 0.196". The kit comes with four segments and one nut, which is enough to make a 4.5" linear actuator.

They have surprising little play given how smooth their operation is. Friction is very low even with significant axial load (pressure in-line with motion). Torsional load (twisting the nut off-axis) will make the friction go up noticeably, so make sure the structure being moved is constrained to the axis of the lead screw (e.g., use the Linear Motion Kit). Operation seems very smooth even across the segment joints - I wasn’t able to feel where the joint was when moving the nut by hand.

Hand Crank
These are pretty much what they look like. The handle is offset from the axle by 1.5". The whole thing is molded as a single piece of plastic, so the handle does not free-spin. Neither the handle nor its central hole is a standard Vex diameter, so there aren’y many attachment options other than elastics. I think you could tap-drive a 6-32 motor screw into the handle if you tried, though. Could be fun to use these with the worm drives above to make a model milling machine.

16t & 32t Bevel Gears
These are similar in design and construction to the 24t bevel gear used with the differential. All these bevel gears seem to mesh reasonably well with each other, which means they can provide power transfer across a variety of angles. The pitch angle between the new 16t & 32t gears appears to be close to 22.5°, whereas the 24t bevel gear’s pitch angle is 45°. This should allow combinations at 135°, 112.5°, 90°, 67.5°, and 45°. I’m not sure how practically useful all these combinations are, but it does open up some interesting options.

Cams and Followers
The cam followers offer about 2.9" of travel, and have the same type of self-tapping holes that the new linear motion trucks have. There is no clearance between the follower and its mount for nuts, so you have to use screws that don’t protrude out the back, or travel will be limited. It seems like these could be used as a light-weight linear slide for short travel (perhaps in conjunction with the worm drive?).

The cams themselves are pretty much what they appear to be in the picture. It would be nice if Vex posted a function or graph showing the cam’s shape (hight-vs-angle), since it isn’t exactly linear. It seems to flatten out near 0° (the drop off) and 180°. One potentially useful result of these flat-ish spots is that you can mount the two cams back-to-back and the resulting union of the two profiles looks much like a pear cam or an eccentric cam.

Each cam has two of the axle inserts that the high-strength gears use. They can be removed if you need more inserts for your gears (or if you want to fit the cam to a 1/4" square shaft for some reason).

High-Strength Worm Wheels
What can I say - it is great to have these in-hand now!


  • Dean

Could the cams be used to lift an arm?

Yes, I think they could work for that, though I personally would just create a driven linkage system instead.

IMHO The lead screw, U-joints, and high-strength worm wheel seem like the real jewels in this kit for competition. The bevel gears may simplify some mechanisms. The cams and hand cranks seem perfect for classroom demo settings.


  • Dean

Has anyone tried making a constant-torque joint with the U-joints?

And here’s the answer to your cam comment:
The black line is the graph r=theta (constant increase in radius), representing an “ideal” cam.

Thanks for the great overview of the kit! Great details as always!

I ordered my kit when it was first released, but I haven’t opened it yet. This provided some great information about whats inside.

It will be interesting to see if anyone thinks of a away to expand the robot with rotary cams, or even a scoring mechanism could be used. It will be an interesting product, indeed.