4" Omni Wheel Spoke Lock
Entry ID #: 7574
Created: Sun, Jan 12, 2020 12:31 AM
Introducing XD Robotics custom made 3D printed part for the Make It Real CAD online challenge, the "4 Inch Omni Wheel Spoke Lock". This is an attachable part that can interlock with a 4" omni wheel to help reduce slip, or play, between a robots wheel and the shaft or gear it is attached to. Many times in VEX, teams will use different gear ratios in connection to the wheels on their chassis to help them in according to the current game, whether it be gearing up a chassis to make it faster, or gearing it down to provide more torque. In both instances, a gear is connected to the same shaft that each wheel rotates on. Many times when this happens, a slight amount of slop can occur, due to the gear and the wheel not consistently and uniformly turning together, whether it be due to the lackluster inserts on VEX gears or the difficulty in pairing a gear and a wheel together. This issue can be seen in the autonomous portion of a match. For example, say you want your chassis to move forward 100 ticks within the motor. If the gear and the omni wheel on the chassis are not completely in unison, this value of 100 ticks could end up being off due to the excess slop that VEX omni wheels experience when coming to a stop. If this measurement was off three ticks, for example, the autonomous could end up being off up to 30 ticks if the robot was supposed to do 10 separate tasks during the autonomous period. So, the overall solution to this issue is making a better connection between your robots gear system and wheel, which is what the 4" Omni Wheel Spoke Lock accomplishes. This 3D print is inserted into the spokes of the 4" omni wheel and attaches to the gear parallel to the wheel on a unified shaft. This ensures that whenever the gear rotates, the omni wheel rotates and vice versa. This will, overall, help with providing more consistent and accurate readings for your robot during the autonomous period, allowing for your robot to be more successful on the field. To make this part, we used Autodesk Inventor 2019 Version 2019.0.1. We started by downloading the VEX part library to be able to measure out the 4" omni wheel. After taking the measurements, we formed our part to be able to fit within the spokes of the wheel, while also creating holes that would line up with a gear on the other side of the part. Using Autodesk Inventor, we were able to render visual models in order to preview the part and view it standing alone, connected to a gear, and while attached to the 4" wheel. Through this project, we familiarized ourselves with, not only Inventor, but also how to make custom 3D printed parts in general. Being a VEXU team where all 3D printed parts are legal, this is a crucial trait to be able to have throughout the building process of our robot. Computer Aided Design (CAD) allows us to extend the boundaries a little wider than VEX parts allow us to, as well as be more creative with different materials not commonly seen in VEX. In addition, CAD is an essential tool to a handful of our team members career path in the future, as one of our members is studying mechanical engineering, while another is studying construction management, both fields where a software such as Autodesk Inventor will be used frequently. Overall, while completing this challenge, we learned many things that not only help the quality of our robots in Tower Takeover, but also help us in our future careers.