Our Elementary Robotics Club is working with the VEX Go City Technology Rebuild STEM Lab. Having mostly experienced VEX IQ, I thought the Competition Advanced Hero Robot was difficult to operate for the game - the controller was imprecise and the arm was too fast. It didn’t seem like coding the motor velocity in the Code tab affected the robot in the Drive tab. Does anyone have ideas on how to improve the driveability of this robot - coding, drive train/device design, alternate controller (we are using Chromebooks), etc.? Suggested improvements would be welcome!
If I remember correctly, the user Code tab has no bearing on the Drive Tab. If the robot is too fast, perhaps they could try gearing it down. Also, “Hero bots” are generally designed as a platform for students to improve on. I would suggest you have a conversation with students to identify areas of improvement on the design and then brainstorm how to implement those changes. What age students are you working with?
Hey @Jonathan_Haynes, as Mark said it, the
Being able to use a pre-built robot to compete in these challenges makes it a little easier to see improvable spots, rather than having to design a robot from scratch. It’s great y’all have found a spot to begin making alterations! Also to Mark’s point, I also do not believe the Code tab of VEXcode GO affects the Drive tab, which means we can alter the speed of the arm/bot through more mechanical means.
A common tool easy to implement is the use of a gear train, like you mentioned. I’ve gone ahead and altered the gear train introduced in step 13 of the Competition Advanced Build Instructions, please see the image below. The only things that are changed include the green gear on the green shaft.
What you see before you is a stacked gear train, and this has now increased the torque found at the blue shaft, meaning it now spins a lot slower than before. By looking at the math involved, option 1 (the build instructions) at a constant input of 50 spins per minute would mean the arm motor would raise at a blistering 16.7 spins per minute. Through the use of gears and understanding gear ratios (option 2), our same input of 50 spins per minute is now reduced to nearly half from before, or 8.3 spins per minute.
The usage of gear trains can be tuned and applied in many different spots, I just wanted to show the more technical and practical application of understanding the math behind it.
I implore you to try the stacked gear train from above for yourself! These gear trains can also be applied to the drive trains to slow your bot more mechanically rather than relying on the drive tab in VEXcode. And for a better driving experience, utilizing touch-screen tablets instead of trackpads found on laptops allows for greater control and maneuverability of the robot. Let me know if you need any additional help in further creating gear trains!
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Hey @Matthew_Goodwin and @Jonathan_Haynes,
Always love seeing ways the “Hero bots” can be improved.
@Matthew_Goodwin, I believed “Stacked gears” are called compound gears?
From ChatGPT:
Compound gears are a type of gear system that consists of two or more gears mounted on a single shaft. In a compound gear system, the gears are arranged in a way that allows them to work together to transmit torque and rotation from one shaft to another.
The gears in a compound gear system can have different sizes, which allows for the transmission of different amounts of rotational speed and torque between the two shafts. In addition, the gears in a compound gear system can be arranged in different configurations, such as in a series or a parallel, to achieve different gear ratios and rotational speeds.
Compound gears are commonly used in machinery and mechanical systems, such as in automobiles, bicycles, and industrial equipment, to transmit power and motion from one component to another.
You’re right, “compound gear train” is more of the technical name; I always went by the informal “stacked gear train” because it helped me visualize what was actually happening, that the gears were literally stacked on one another. One of the coolest gear trains in my opinion!
@Jonathan_Haynes How have you been finding the Competition Advanced Hero Robot? Have you been able to make any changes to it in order to better suit your needs? Here is a great article from the VEX Library on the Progression of Building for VEX GO, outlining helpful tips whenever it comes to making modifications to your build! Please let us know if there is anything else we can learn with you!
