Looking for the UltraPlanetary Gearbox System (REV-41-1600)? Check out the UltraPlanetary Gearbox System Overview in our Crossover Documentation.
The MAXPlanetary System (REV-21-2100) is a cartridge-based modular planetary gearbox designed from the ground up for NEO-class motors. The design of the MAXPlanetary has been carefully optimized to provide torque density unavailable in FRC up until now.
The MAXPlanetary is intended for use with the NEO, NEO 550, Falcon 500, and 775 motors. Building on the ability to iterate and adjust designs easily, the MAXPlanetary System consists of lubricated cartridges allowing for swapping gear ratios on the fly and with ease. Users can configure a single-stage planetary using one of three different reduction cartridges or build multi-stage gearboxes by stacking individual cartridges together. The user can use the included 1/2in hex shaft or use a custom length of hex shaft best suited for the application. The gearbox also provides two mounting options, face mount and side mount, for ultimate flexibility in your robot design.
Looking for the Ultra 90 Degree Gearbox (REV-41-2080)? Check out the Ultra 90 Degree Gearbox Overview in our Crossover Documentation.
Designed with an efficient right-angle configuration, the MAX 90 Degree Gearbox offers a robust and high-performance solution to building a more compact robot. Connect the MAX 90 Degree Gearbox to the MAXPlanetary System in a 90-degree orientation for maximum flexibility and ease of use in tight spaces. The through bore design of the gearbox allows for easy mounting and integration into a wide range of applications. Its 90-degree output orientation provides a compact and efficient way to transmit power and torque at right-angle configurations.
The REV Robotics MAXPlanetary Gearbox includes the following features:
Three different, self-contained gear ratio cartridges providing twenty-seven gear ratios ranging from 3:1 to 125:1
High torque density
Easy assembly without modifying the motor
A Socket 1/2in Hex Output with the ability to retain a shaft blind
Assembled front to back for ease of changing the gear ratio while the MAXPlanetary Gearbox is mounted on the robot
When assembling the MAX 90 Degree Gearbox we recommend adding grease during assembly and re-applying as needed for the maintenance of your mechanism. For most applications, using White Lithium Grease or Red Tacky Grease will provide sufficient lubrication.
Input Spline - Accepts torque from the previous stage while being easy to insert and remove.
Output Spline - Provides torque transfer between one stage and the next while being easy to insert and remove.
Assembly Holes - The screws holding the gearbox together pass through these holes.
Shields - Keeps the internal components of the gear stage in their place when the stage isn’t assembled into a gearbox. Also retains grease to keep the gear stage lubricated throughout its service life.
Alignment Tabs - Alignment features that engage with the alignment notches on the previous stage. The directional nature of the alignment features prevent the user from assembling any gearbox components backwards.
Alignment Notches - Provides a socket for the alignment tabs to engage with. These features keep the rotating components concentric as well as providing angular alignment to keep the flat faces of the gearbox in plane.
Side Mounting Holes - These 10-32 holes allow the gearbox to be mounted on top of structural components without obstructing the front of the gearbox.
Assembly Holes - The screws holding the gearbox together pass through these holes.
Alignment Notches - Provides a socket for the alignment tabs on the first gear stage to engage with. These features keep the rotating components concentric as well as providing angular alignment to keep the flat faces of the gearbox in plane.
NEO Mounting Holes - These holes are for mounting NEO-class motors to the input block.
550 Mounting Holes - These holes are for mounting the NEO 550 to the gearbox.
775 Mounting Holes - These holes are for mounting 775-series motors to the gearbox
775 Vent Holes - These holes line up with the vent holes on the face of 775-series motors and allow cooling air to pass through the motor.
Socket 1/2in Hex Output - Engages with a 1/2in hex shaft to drive a robot mechanism. The output includes a #10 clearance hole through the middle which allows a shaft to be retained in the output.
Face Mounting Holes - These 10-32 holes allow the gearbox to be mounted to the face of a bracket or tube in several useful orientations.
Side Mounting Holes - These 10-32 holes allow the gearbox to be mounted on top of structural components without obstructing the front of the gearbox.
Threaded Assembly Holes - The screws holding the gearbox together thread into these holes to clamp the gearbox stack together.
Input Spline - Accepts torque from the last gear stage while being easy to insert and remove.
Alignment Tabs - Alignment features that engage with the alignment notches on the last stage. The directional nature of the alignment features prevent the user from assembling any gearbox components backwards.
All 10-32 Screws used for Assembly and Mounting
10-32 Face Mounting Holes on a 2in Bolt Circle with 2 Orientations
2in Gearbox Height
Gearbox does not protrude above or below common FRC structural tubes
Output shaft stays on 1.0in pitch when the gearbox is mounted using the side holes
Side Mounting Holes are on a 0.5in pitch regardless of number of stages
The MAXPlanetary is a modular planetary gearbox designed for use with NEO-class motors and is optimized for torque density. By following these tips and tricks, you can ensure that your gearbox is assembled properly and functions efficiently. With the help of this guide, you will be able to assemble your MAXPlanetary gearbox with confidence and ease.
Attempting to stack the Input Coupler onto the gear cartridges, rather than pressing the Input Coupler into the stack is often more difficult.
1) Place the motor with the motor shaft and Universal Input Stage facing upwards.
2) Slide the Input Coupler on the motor shaft. Ensure that the key is engaged and the Input Coupler has been slid all the way against the motor.
3) Take your stacked output stages and gear cartridges and align them with the Universal Input Stage.
4) Slide the stack of gear cartridges onto the motor shaft and input stage. Ensure that the input spline on the rear gear cartridge and the input coupler is properly engaged.
Note: This may require twisting the gear cartridges by hand slightly to line up the splines, and then rotating back once the spline is engaged. Make sure the entire stack is pressed together and all alignment features are properly engaged.
5) Make sure the stack is fully seated and no gap is present between the stack and the input plate before inserting and tightening the gearbox assembly screws.
Keep in mind that it may require a decent amount of force to couple the gearbox stack with the motor- it is not expected to be a slip-fit.
The REV Robotics MAXPlanetary System includes the following features:
Three different, self-contained gear ratio cartridges providing twenty-seven gear ratios ranging from 3:1 to 125:1
High torque density
Easy assembly without modifying the motor
A Socket 1/2in Hex Output with the ability to retain a shaft blind
Assembled front to back for ease of changing the gear ratio while the MAXPlanetary Gearbox is mounted on the robot
Input Spline - Accepts torque from the previous stage while being easy to insert and remove.
Output Spline - Provides torque transfer between one stage and the next while being easy to insert and remove.
Assembly Holes - The screws holding the gearbox together pass through these holes.
Shields - Keeps the internal components of the gear stage in their place when the stage isn’t assembled into a gearbox. Also retains grease to keep the gear stage lubricated throughout its service life.
Alignment Tabs - Alignment features that engage with the alignment notches on the previous stage. The directional nature of the alignment features prevent the user from assembling any gearbox components backwards.
Alignment Notches - Provides a socket for the alignment tabs to engage with. These features keep the rotating components concentric as well as providing angular alignment to keep the flat faces of the gearbox in plane.
Side Mounting Holes - These 10-32 holes allow the gearbox to be mounted on top of structural components without obstructing the front of the gearbox.
Assembly Holes - The screws holding the gearbox together pass through these holes.
Alignment Notches - Provides a socket for the alignment tabs on the first gear stage to engage with. These features keep the rotating components concentric as well as providing angular alignment to keep the flat faces of the gearbox in plane.
NEO Mounting Holes - These holes are for mounting NEO-class motors to the input block.
550 Mounting Holes - These holes are for mounting the NEO 550 to the gearbox.
775 Mounting Holes - These holes are for mounting 775-series motors to the gearbox
775 Vent Holes - These holes line up with the vent holes on the face of 775-series motors and allow cooling air to pass through the motor.
Socket 1/2in Hex Output - Engages with a 1/2in hex shaft to drive a robot mechanism. The output includes a #10 clearance hole through the middle which allows a shaft to be retained in the output.
Face Mounting Holes - These 10-32 holes allow the gearbox to be mounted to the face of a bracket or tube in several useful orientations.
Side Mounting Holes - These 10-32 holes allow the gearbox to be mounted on top of structural components without obstructing the front of the gearbox.
Threaded Assembly Holes - The screws holding the gearbox together thread into these holes to clamp the gearbox stack together.
Input Spline - Accepts torque from the last gear stage while being easy to insert and remove.
Alignment Tabs - Alignment features that engage with the alignment notches on the last stage. The directional nature of the alignment features prevent the user from assembling any gearbox components backwards.
The following torque measurements are for a static load condition. The torques listed are for the output of the stage.
3:1 Cartridge
Tested to 290 N⋅m (no failure)
4:1 Cartridge
Fails at 270 N⋅m
5:1 Cartridge
Fails at 240 N⋅m
1/2" Hex Socket Output
Fails at 250 N⋅m
Shock loads can cause the gearbox to fail in situations where the steady-state torque is still within allowable limits.
Cantilevered load on the output shaft puts additional stress on the gearbox and will reduce the torque the gearbox can withstand.
The following chart shows which gear cartridge configurations are allowable with different motors. Cells shown in GREEN are allowed and cells shown in RED are not allowed.
These ratings are based on the default current limit on the Spark MAX (or Talon FX). Increasing the current limit increases the maximum torque the motor can produce and may put components of the gearbox outside of their load rating.
Gearbox ultimate strength - Failure at 180 NM +/- 5%
Please note that this is less than the MAXPlanetary Gearbox can withstand!