Vex VRC Walkerbot

Hello everyone, this is not a Walkerbot Showcase. Rather, I’m asking if in the current robots being able to push other robots meta, a heavy, not wheeled bot would be viable. The design in my head is something similar to Chomp from s5 of battle bots but less complicated. Without the wheels, you’re basically pushing around 30 pounds of robots that has no wheels to push around on, either greatly slowing you, failing, or simply not for fear of getting DQ’ed for intentional tipping and/or field damage, as it could tip from the larger amount of friction on one set if it is slightly raised. This design would use 6 motors for 10 legs (2 sets of 2 and a middle singular one per side), a DR4B with a pneumatic clamp, and a claw on the back. This would be 17’~ long and 16’~ wide, and 17’~ tall. This design would be slow, at about 80 RPM, as some torque would have to be put into lifting the bot, and the program would run 2 motors (1 per side) at a time, wait .25 seconds, and repeat until all the way through, using the buttons on the face of the controller for movement of the robot, and the L/R buttons for the clamp and claw, with a stick for the up/down controls for the DR4B. This is just an interesting idea for a brick wall that just won’t move if it doesn’t want to.

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What an extraordinary idea. I don’t know what to say.

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I don’t have much experience with walkers but I would love to see how much power it would have and if it could successfully counter the turtling strat by dragging the other bot. It would also be interesting to see how well it could climb the platform. So if anyone has the time please do build it, I’m intrigued.

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Firstly, how fast do you intend the walking mechanism to be? Because if the robot is too slow, faster teams can just zoom around it. Also why a DR4B for the lift? A 4 bar would work just fine for offloading, and without a ring intake the height a DR4B gets is pretty much useless. Also, I bet you could code the joysticks to work just fine with the walking mechanism, which means you would have to use other buttons for the lift, which is what virtually every team does anyways.

Also talking about the field damage DQ, G12 pretty much spells out rules for defense (teams should design robots that aren’t easily tippable), and R4 spells out the rules for damaging the field. As the walking mechanism could potentially damage the field, as a ref I would be hesitant on any R4 related DQs knowing that the robot being tipped over has a higher than normal propensity to damage the field (as very few robots would have subsystems like yours).

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Continuing on the Battlebots analogy, Chomp got a bonus of 250 extra pounds to play with, so it was a 500 pound bot against a 250 pound bot. It also went 1-3 with that bonus. I don’t care about your design; without any sort of bonus for walker bots, that isn’t feasible.

If you want to go down that path, how are you going to incentivize people to build walkers?

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The reason I would not program it with the sticks for ‘drive’ is because I’m to dumb to make it not lock itself up in an endless loop of being told to execute the start of the command. The DQ’s I talked about are rather than specific design, referring to reasons that other teams would not want to push you around, for fear of it happening and the ruling not going in their favor after the match. Lastly, to address the first point you made, it would go as fast as the gear ratio required to keep it up allowed, 80 is just a ballpark guess. In short, this is designed in my head to be an immovable wall that gets Judges’ Awards for its design and creativity, not an overly competitive robot. One thing I forgot to mention: the DR4B is so that you can get stuff consistently onto the platform, and being likely twice as long as a 4b, while at its extent, opponents want to push it even less because of it being an even more heavy brick wall, especially near it’s center of mass (witch would be pushed forwards by the goal, into where you would probably push it from.

I based the movement and shape roughly off Chomp, nothing else. Also, Chomp has always been about advancing the sport, not winning.

Another reason I made this post is because the last time anyone has made a vex walker, and shown proof of its existence to the internet, from what I can find, is 2014 with this YouTube video https://m.youtube.com/watch?v=jPzSYzW-A4E
The only other one I found is a series of videos in 2008 by Innovation First (channel https://m.youtube.com/channel/UCNEVMox4XpdLhOjHSEo-R8Q)

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I Built a Quadrupedal Drive

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Cool! I likely didn’t find this because I google and bing search ‘Vex Walking Robot’. I’m glad to see people are still trying to create walkers. Is your video unlisted? It should have showed up from the keywords in my search.

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It would be really cool to try and build a walking robot, but I don’t think it would be at all competitively viable.

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It’s not mine, @Sylvie made it a while ago.

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Perhaps not for most years, at least in the w/l/t column, but in games where aggressive contact is allowed, like Tipping Point, it may have a tiny niche as a slow yet unmovable wall that will just keep chugging along, and can’t get pushed. The walker can just go on defence while your teammate goes on offense, and you just walk into whoever is trying to get into your home zone’s territory, and they would both have to leave their zone vulnerable to your teammate getting their mogos, while you can still offer resistance.

Now let’s look at the current Judge’s Guide to see what the “Judges’ Award” is actually for:
“The Judges Award is presented to a team that is most deserving of special recognition.
Key criteria:
● Team displays special attributes, exemplary effort, and perseverance at the event
● Team overcomes an obstacle or challenge and achieves a goal or special
accomplishment at the event or at some time throughout the season
● Team distinguishes itself in some way that does not fit under other award criteria but
nonetheless deserves special recognition
● Students demonstrate teamwork and effective communication skills”

Nowhere does this award mention a creative robot design/iteration. I think the award you are referring to is the Create Award, which is to be awarded based on the following criteria:

“The Create Award is presented to a team who has built a robot that incorporates the most
creative engineering design solution to the challenges of this season’s game.
Key criteria:
● Robot design incorporates a creative design solution
● Team has demonstrated a highly creative design process and methodology
● Team has committed to ambitious and creative approaches to solving the game
challenge
● Students understand and explain how they worked together to develop their robot”

Knowing which judges awards your team is aiming to win will get y’all one step further to achieving that goal. Yet the majority of local, qualifying events do not offer the aforementioned award (plus it will not qualify your team to your respective Regional Championship), and the chances of it qualifying your team to the World Championship is slim and depends on the qualifying spots awarded to your region as per the Qualifying Criteria. Also, to get the create award, your team would need to give strong reasons as to why your drivetrain, which close to 99% of teams do not use, solves the game challenge to the judges and thoroughly explain the creativity of your engineering design process, and how your engineering notebook (which is usually required to get a judges interview in the first place) fully records it.

Another point, the DR4B would get you twice the height as a 4-bar of the same dimensions, but not twice the horizontal length. For this season’s game, a DR4B is totally overkill as the platforms can be reached by a standard 4-bar or 6-bar (I have even seen some teams using 2-bars to offload mobile goals onto the platform). Also, with a slow speed of 80 rpm, any fast robot can easily speed right past you.

Now nowhere am I bashing your design. As a matter of fact, I think it would be totally cool to see a competitively viable walking robot in VRC. I really hope you expand upon and finalize this design, and compete with it soon!

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I’d love to be proven wrong, but a walking robot just seems worse in every aspect to a normal wheeled one. If pushing resistance is what you’re after, you can use pneumatic brakes if you really want to, which accomplish the same thing without sacrificing the ability to effectively move around.

I think it would be a really great side project though.

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If your goal is to be able to not be pushed around, there is a design I saw back in Turning Point which allowed the team to stay on the middle parking platform without being pushed. I don’t have a photo of it, but they had a large adhesive pad under their robot. They then could raise/lower it with a motor (however this could be done with a pneumatic). It was impossible to push off the platform, and worked very well for them. Another option you could use is tank treads, but they made it very difficult to turn. Walkers are simply too slow and too heavy to be extremely competitive in VRC.

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True. Walkers right now will never be good, but it will be cool when someone can create one light and fast enough to be viable. This is more of a mechanical thing that won’t do good, and often (at least in my local competitions), Judges Awards are given to teams with interesting and unique designs, or if they are in a mixed tournement, giving a Judges Award to a middle school team if there isn’t enough middle schoolers to justify a split in the design or exellence catagories. Maybe thats just my reagion though.

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Going down that rabbit hole, if Walkers ended up getting similar bonuses, I would go to 22’ inches, like the bigger of the 2 VEXU robots, and more motors. This would be different for each specific subcategory.
A ‘Chomp’ Walker would get +6 motors, a Biaped gets +2, a Quadruped and Hexaped would get +4 (Chompsand H.Peds are differed, as hexapeds, if you’re smart about it, could use less that six motors) An Octaped would get either +4 or +6, depending if people figured out how to share motors over legs. A Chomp Walker has at least 10 platforms, with equal on each side. Lastly, Shufflers would get +10 (this number would go down if people figured out how to share motors across shufflers)

our school built one last year if anyone wants to take a look. https://twitter.com/i/status/1349082309677473798

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note this was done with 2 motors

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