Robotics Education & Competition Foundation
Online Challenges

V5 Motor Cooling System

1

TecTigers3389C
Entry ID #: 8400
Created: Fri, Dec 4, 2020 3:57 PM


The V5 Cooling Fan

Overheated motors are and have been a very serious problem that VEX robotics participants have had to deal with for years. High temperatures in motors cause several problems, including loss in performance, and shorter lifespans. Over time, participants have attempted to solve the problem by using different methods. 

 Some teams have tried using cans of cooled, compressed air. While this method is effective in the cooling of the motors, it has two major drawbacks. The first drawback to using compressed air is that it does not provide an equal amount of air to every part of the motor. Instead, some parts, generally the ones closer to the nozzle of the can, get much more cooling than the ones farther away. This uneven cooling can be catastrophic to the motors and their lifespan. Another major drawback is that using compressed air is terrible for the environment. Not only do some products contain harmful chemicals that are up to 300 times more harmful than carbon dioxide for the atmosphere, but they tend to not be usable for more than a competition or two. This is extremely wasteful as the containers are not reusable, and just end up in landfills.

Other teams have tried to let their robot sit for a while without being used. This method is not only extremely ineffective, but can take a very long time as well. Through competition experience by 3389C, it has been deduced that it can take over 10 minutes for motors to even begin cooling if they have been strained. Even if adequate time is allotted to the motors for cooling, they do not stay cool for very long. Usually, they will heat up within a match or two. Also, in heated competitions, some teams simply don’t have the time to let their robot just sit there for several minutes at a time.

Thus, while these methods have given some relief, none of them have proven to be “winners”- both reliable and effective at the same time. 

Our solution to this problem is the v5 cooling fan. This product is designed to aid teams facing problems with cooling for their motors. It features a 58 mm fan mounted to a versatile clip designed specifically to hold on to a v5 motor. The case features two points of ventilation, providing optimum airflow for the fan. It clips around the side of the motor and has a section cut out so that wires can go through it with ease. The fan will ideally be programmable as either a three-wire electronic or as a motor in VEXcode, along with other platforms. An example of code that would be written by a user to execute a basic function using the fan is provided in a photo using VEXcode v5 text. There is also an on/off switch located on the side panel for manual activation. Circuit drawings are also available in picture format. The fan motor is a standard brushless motor, that can either come with or without the fan, and is attached to the unit through 2 crossbeams stretching from either side of the top of the unit. In the attached budget/research project, the approximate price has been calculated using the fan coming with the motor. Located on top of the unit is a filter, which will block out debris from getting blown into the motor.

This assembly was created using Autodesk Inventor Professional 2020. We also applied material textures to the parts to make the assembly look more realistic. To generate the renders, we used the ray tracing feature in Autodesk Inventor, to write the code example, we used VEXcode v5, and to create the animations, we used Fusion 360. 

This project increased our knowledge and comfort with using Autodesk Inventor, and CAD software overall. The applications for these softwares are endless. For example, we design our entire robot in CAD before building it because it is much easier to put together assemblies and take them apart on a computer than it is to actually build it. 

 

Research and Budget Calculations:

 

The cooling fan for this project will most likely be custom made for VEX to mass-produce (like the v5 motor lineup), however, we were able to find a fan with similar dimensions/specifications as the intended product to give a simulation of the average price/ overall performance of the product. 

This technology is already in application for computers, and has been for several decades. Computers generate several times more heat than v5 motors and require much more cooling, so this technology is already proven to work in applications worse than motors, which proves that it will be reliable and effective for motors. 

This fan, made by StarTech, roughly matches the dimensions of the motor used by our v5 cooling fan setup, mainly in its diameter. It is designed to cool CPUs, which require much more cooling than the v5 motors, which gives some insight into the effectiveness of the cooling fan setup. At just $12.03 this cooling fan/heatsink is not only cost-effective as it is, but will likely be even cheaper for VEX to customize/ bulk order/mass produce it. 

After looking at the specifications rather closely, it can be seen that it is rather thick, and would not be able to fit into the specifications required for the v5 cooling fan. However, it is important to remember that these specifications can be adjusted by VEX, as they will likely be ordering these in bulk, but also that this dimension includes the heatsink, which is not necessary for the v5 cooling fan.

 

Estimated Cost for VEX to produce one cooling unit (not including wholesale deals):

 

Item                                           

Estimated Cost

Fan Unit

~$12

Custom Motor Attachment Clip

~$2.50-3.00

Filter

~$1-2

Electronics

~$0.75-1.50

Total Cost:

~$16.25-18.50

 

(This is not including wholesale deals, so in reality, this projection is more expensive than the actual product likely will be)