2023 REV ION FRC West Coast Drivetrain Build Guide

Assembly Instructions

2023 REV ION FRC West Coast Drivetrain Assembly Instructions

Bill of Materials

CAD Assembly - Onshape

Suggested Tools and Suggested Materials

Cutting

Teams will need to cut some pieces of structural tubing in order to build the 2023 REV ION FRC West Coast Drivetrain. The following sections detail the quantity and length needed for each type of extrusion.

Every piece of structural tubing needs to start with a hole 1/2in (or slightly less) from the end where the length measurement is taken FROM.

• 2x1 MAXTube:

  • 2x26-1/2in (Front/Rear Rails)

• #25 Chain

  • 4x28in (112 links)

Drive Module Subassembly

Build two of the following Drive Module Subassemblies:

Structure

1) Slide 3/4in long #10 spacers inside the 31in long 2x1 MAXTube with MAX Pattern and line them up with the holes shown.
2) Slide 1-1/4in long #10-32 button head screws through the holes in the MAXTube and through the spacers.
3) Position 2-Hole (5in long) 2x1 MAXTubes with MAX Pattern on the exposed ends of the screws. The tubes should be turned on their sides, flush with the top of the 31in tube, and located 7in from the end of the 31in tube. The side of the 31in tube these tubes are installed on will become the “outboard” side of the drive module.
4) Install nylock nuts on the ends of the screws, inside the 5in long tubes. The nuts will engage with the slots inside the MAXTubes, so no tool is necessary to hold them in place. Tighten the screws down.
5) Locate the middle MAXSpline on the 31in tube. Insert a Structural MAXHub in the two (2) MAXSplines on either side of the center one on the outboard side of the tube. Rotate the hubs so that their threaded holes are located along the centerline of the tube (i.e. on the left or right side).
6) Insert two (2) plastic MAXHubs aligned with the Structural MAXHubs on the inboard side of the tube. Rotate the hubs so that their threaded holes are on the opposite side (left/right) from the Structural MAXHubs.
7) Fasten the MAXHubs in place with one 1in long #10-32 button head screw and one 1in long #10-32 socket head screw for each MAXHub pair. The socket head screw should be installed through the plastic MAXHub and threaded into the Structural MAXHub. The button head screw should be installed through the Structural MAXHub and threaded into the plastic MAXHub.
8) Insert two 2-1/2in long rounded hex shafts into the plastic MAXHubs (one shaft in each). Push them in all the way up against the Structural MAXHub.
9) Fasten the shafts in place with 1/2in long #10-32 button head screws.

Wheels

1) Build two of the following: a. Insert two aluminum MAXHubs into each side of a traction wheel. Rotate the hubs so that their threaded holes are 180 degrees apart. b. Fasten the MAXHubs in place with two 1in long #10-32 socket head screws.
2) Build four of the following: a. Insert two aluminum MAXHubs into each side of an omni wheel. Rotate the hubs so that their threaded holes are 180 Degrees apart. b. Fasten the MAXHubs in place with two 1in long #10-32 socket head screws.

Powertrain

1) Form two of the #25 chain lengths into a loop. This can be accomplished with a chain tool or by removing an extra link and using a connecting link.
2) Place the chain loops on either side of a 16T #25 double sprocket.
3) Insert a 6in long Hex Shaft into the 16T double sprocket.
4) Loop the opposite ends of the chains around two more 16T #25 double sprockets (one for each chain). Ensure that each chain is installed on either the front or back of the sprockets (e.g. not on the front of one sprocket and on the back of the other sprocket).
5) Slide two 4in long Hex Shafts into the outer sprockets (one in each sprocket).
6) Slide two Rounded Hex Bearings onto the ends of the shafts (one on each shaft).
7) Install two Rounded Hex Bearings in the center MAXSpline of the MAXTube (one on either side of the tube).
8) Line up the chain assembly with the MAXTube and insert the center shaft into the bearings in the middle of the tube. The sprockets and chain should be located on the inboard side. Insert the shaft through both bearings, but don’t push the middle sprocket all the way against the bearing.
9) Slide the 4in shafts with bearings into their associated MAXSplines in the MAXTube. Slide the sprockets and chain up against the bearings as this is done. This may require a significant amount of force to achieve, as the chain is supposed to be very tight.
10) Slide two Rounded Hex Bearings onto the outboard ends of the 4in shafts and into the MAXSplines in the MAXTube. Tension will have to be applied to the chain in order to get the bearings into the MAXSplines. The shafts may be used as levers to tension the chain and line up the bearings. This may require a significant amount of force to achieve, as the chain is supposed to be very tight.
11) Install one 1/8in wide Shaft Spacer and one 1/16in wide Shaft Spacer onto the outboard side of the center shaft.
12) Install one of the traction wheel assemblies onto the center shaft. If necessary, slide the shaft so that it is flush with the face of the MAXHub on the outside of the wheel. It may require tapping the shaft with a small rubber mallet to move it with the chain tension in place.
13) Install two of the omni wheel assemblies onto the outer shafts. If necessary, slide the shafts so that they are flush with the face of the MAXHub on the outside of the wheel. It may require tapping the shaft with a small rubber mallet to move it with the chain tension in place.
14) Retain the three wheels with Shaft End Screws.
15) On the inboard side of the center shaft, install one 1/16in wide Shaft Spacer, one 1/4in wide Shaft Spacer, and one 1/2in wide Shaft Spacer.
16) On the inboard side of each of the outer shafts, install one 1/8in wide Shaft Spacer and one 1/2in wide Shaft Spacer.
17) Retain the outer shafts with Shaft End Screws.

Gearbox Mounting

1) Assemble a 2 Motor Drivetrain Gearbox with the gearset for 6in wheels with the pinions for the desired speed. If you are unsure of how to do this, you can find the directions here: 2 Motor Drivetrain Gearbox Build Guide
2) Ensure that the body screws put into the lower spacers are inserted with the screw head on the opposite side of the motors. The nylock nuts must be removed for this step as well.
3) Slide the gearbox onto the end of the center shaft and thread the exposed screws into the ends of the standoffs (2-1/2in hex shafts). Tighten the screws down.
4) Retain the center shaft with a Shaft End Screw.

Final Subassembly

1) Arrange the two assembled drive modules and the two 26-1/2in long tubes (“front/rear rails”) as shown. The ends of the front/rear tubes should be flush with the 5in long MAXTubes between the wheels.
2) Position eight 90 Degree brackets on each corner, top and bottom, and use 3/16in rivets to rivet them in place.
3) Assembly is complete- begin the rest of your robot assembly, or begin following the 2023 REV ION FRC Starter Bot Assembly Instructions!

Want to integrate this drivetrain with your 2023 Starter Bot? Check out the Integration Steps!