How to Design a Combat Robot Drivetrain (Motors, Gearing and More!)

Рет қаралды 10,100

Күн бұрын

How to design the drivetrain for combat robots (or any robot for that matter).
In this video, I take a very in-depth look at what factors will help with selecting a motor and gear ratio for your desired robot drivetrain setup. The guide I've linked below will also go into detail about how to achieve the desired ratio and transfer torque to the wheels of your robot, and more. If there's enough interest I'll expand on these topics in a full Part 2 video.
If you're working on a design now, feel free t follow along as I go through the calculations I did for designing my 12lb combat robot Draconid!
Design Guide Document: bit.ly/DriveDesignGuide
Calculations Spreadsheet: bit.ly/JustCuzDriveCalc
Timestamps:
0:00 Intro and discussion of the topic
2:51 Spreadsheet explanation
6:36 Walkthrough of calculations for Draconid
9:05 Gear Ratio discussion
11:38 Relating to Team Tentacle Torque Calculator
13:20 Motor Speed and Torque Graphical Analysis
14:30 Traction Limit Explanation
17:16 Real-world speed/acceleration from motor
19:07 Conclusion
Draconid vs. His 'N Hers fight: • Motorama Robot Conflic...
Just 'Cuz Robotics Website: justcuzrobotics.com/
Just 'Cuz Store: justcuzrobotics.com/shop
Instagram: @JustCuzRobotics
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@bloodsport_battlebot
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Bloodsport Facebook Page:
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Music provided by Argofox:
Road Lizard - Interloper
• Road Lizard - Interlop...
Arcturus - Liftoff
• Arcturus - Liftoff [Ar...

Пікірлер: 27

@edwinharding613 8 күн бұрын

You got me a first class in my engineering module in uni, thank you 🙏

@lunarwinds2000 3 жыл бұрын

My head exploded! Seriously thank you for explaining part of how it takes more than just strapping motors and batteries together to make a seriously competitive Battlebot

@temoherbertlopez6019 4 жыл бұрын

I love you channel, your videos are very informative and your robots are cool, you are the best.

@JustCuzRobotics 4 жыл бұрын

Thank you!

@Dreadcaptainrobert 3 жыл бұрын

thanks for posting awesome content

@TheBlackEventorizon 4 жыл бұрын

Yes! It can be done! I've been looking at 3D printing double helical gears for a while, and it seems they are viable!

@JustCuzRobotics 4 жыл бұрын

Yup absolutely. Herringbone gears work great. I used a free Fusion 360 helical gear addon to generate them.

@TheBlackEventorizon 4 жыл бұрын

Thanks! I have Solidworks and have tried lofting the profiles from regular spur profiles. The few I have printed did work, they just needed an offset to account for the excess material during printing.

@JustCuzRobotics 4 жыл бұрын

@@TheBlackEventorizon Not sure what Solidworks package you have but in the one I have for work, the toolbox/parts library includes some helical gear generation tool as well.

@TheBlackEventorizon 4 жыл бұрын

@@JustCuzRobotics Ah, I think Toolbox is part of Professional, I only have Standard. But I do have a 2D gear generator that I have turned into 3D gears. I'll just experiment!

@MikeysLab 3 жыл бұрын

Awesome video, thank you :) looking to leanr how to use fusion 360 more professionally, not just building part, but making assemblies and testing motion, is there a tutorial you can recommend?

@JustCuzRobotics 3 жыл бұрын

Product Design Online has a few good ones on KZfaq as does Lars Christiansen

@MikeysLab 3 жыл бұрын

@@JustCuzRobotics thank you, I appreciate it😁

@robertgrassiDMD 2 жыл бұрын

When you're designing a timing belt with no idler, do you purposefully make center distance a little shorter than the "perfect" length of the belt? That way, if the belt is 1/16" loose, it still runs, but being 1/16" too tight and maybe you can't get it on, or it's just putting too much friction on the shafts? Will the kevlar reinforce belts just stretch? For instance my center distance is about 5 inches, needs a theoretical 14.00 inch / 70 tooth belt / 0.2in pitch, do I push the center distance down to 4.9 inches so that there's some slop, so that the theoretical belt length is more like 13.93 inches (making 14 inch belt just a little bit loose, but not more than the pitch of 0.2in). Thanks and great vids, really enjoying them

@JustCuzRobotics 2 жыл бұрын

Kevlar-reinforced belts do not stretch as much as you might think. I would say try and design around maybe 1 to 2 % belt stretch with the center to Center distance such that it is a little bit undersized so maybe like one or two mm bigger than the supposed best center to Center distance. For shorter belt runs like on Division I just did it dead-on and that worked great for me because I'm using toothed pulleys both sides. If you are using toothed pulleys both sides you no longer need to worry as much about the belt tension since the teeth do all the work. 0.1 inches is actually a huge amount that's like close to 1/8 of an inch and that will almost definitely cause a problem. You cannot make the center to Center distance shorter by a value that is greater than the height of one belt tooth or else it'll mean your belt can easily flop away from the pulley

@muhammadarbaz8869 3 жыл бұрын

i've wasted so much time surfing web fr this info🥺 thank u fr explaining this stuff❤️❤️

@JustCuzRobotics 3 жыл бұрын

You're very welcome! That's the idea, it's very specific info and hard to find all in the same place. I'm hoping to eventually have enough videos covering a range of aspects of bot design to help anyone who is starting to take the sport more seriously.

@muhammadarbaz8869 3 жыл бұрын

@@JustCuzRoboticsyeah absolutely it was worth watching💯❤️ i would recommend to make video on different alloys nd materials for bot's body with their prop.

@JustCuzRobotics 3 жыл бұрын

That's definitely an idea on my list of future videos. It's tricky to tackle since I'm not sure exactly what level of detail is ideal for it. Materials science is an easy rabbit hole to fall down, but often times material choice is dictated by more than specs. What you can actually source, what you can afford to buy, and what sort of manufacturing methods you have access to or can afford to pay for are huuuuge factors. I had contemplated making a video that was like comparing every manufacturing method possible but it quickly became a crazy spreadsheet. Most of my important points got condensed into this article maker.pro/custom/tutorial/accessible-manufacturing-options-for-robotics

@muhammadarbaz8869 3 жыл бұрын

@@JustCuzRobotics thanks for the article. i am actually beginner nd currently working on project, ur link has also told me how to choose battery for my project 😂 u r incredible ❤️

@syedqubullah4286 3 жыл бұрын

How you calculated the gear ratio?

@JustCuzRobotics 3 жыл бұрын

I assume you mean how to calculate the real world ratio for a pair of pulleys or gears, since I went over how to calculate the theoretical ideal ratio in the video. This is literally a ratio of diameter, radius, or tooth count depending on what you're measuring. A 24 tooth gear mated to a 12 tooth gear has a ratio of 2:1 (24/12). The result is that every 1 revolution of the 24 tooth gear results in 2 revolutions of the 12 tooth gear, with 0.5X the torque. Or if driving the 12 tooth gear, the reverse is true - every 1 revolution of the 12 tooth results in 0.5 revolutions of the 24 tooth gear, with 2X the torque. Same works for toothed pulleys. For smooth pulleys simply look at the pitch diameter of the pulleys (usually listen when you buy them) and the ratio between those. If you have a pair of random smooth pulleys and no datasheet, the ratio of measured diameters will suffice.