Here is my first bot. I bought 2 Vexplorers from woot because they were $79 each. I had been considering buying one before butat that price I could not resist. I was going to give one of the kits to my Nephew but he had been kind of naughty so I gave him a lump of coal instead .
Once I had the kits I began to mod the claw support assembly so that it would rotate. I did this by super gluing a 60 tooth gear to the hub of one of the Vexplorer wheels to gain stability I then ordered the tank tread kit and as I had a total of 8 motors I gave the tread 4 motors in order to accommodate the increased weight.
The final step was to make a 'wrist" for the claw. I did this by replacing the 84 tooth gears shown in the kit sold with two 60 tooth gears that I drilled 2 holes in.
I had to experiment with finding an optimal balance for the the claw but with testing I have achieved a decent balance.
The resulting bot works very well although the turret rotation could be smoother.
I bought a dual control starter kit that I found on Ebay and I am awaiting delivery. I also bought 4 speed controllers so I can use my Vexplorer motors with the Vex microcontroller.
Yeah i got bored with my Vexplorer and did the same thing with mine except i didn’t use the wheel and gear kind of thing. Mine uses an 12 to 60 gear ratio and the assembly is on a 15 x 5 plate. The only problem with mine is the arm is about and inch above the whole chassis and is probally not as stable as yours is.
Yours still is AWESOME though!!!
I got bored with the two that I bought from woot also. SOOOOO I decided to build a mobile Missile Launcher. I just have to go to walmart and get some extra parts. I am going to use model rockets for the Missiles. But I need a platform for the missiles, a rotating gear setup for the launcher, and better cameras. The back control is going to be where the platform will be. I will keep you all updated and try to link a video when I am done.
If by “model rockets” he means Estes/Centuri-style rockets, safety goggles won’t even come remotely close to making a Vexplorer mobile rocket launcher safe.
I did think about hinging the chassis and I want to put 2 sets of tracks so it will not get stuck. The turning is not that bad on a vinyl floor but when you get it on carpet or anything that is not smooth it drains the battery. Moves like a slig when it turns right now. I am going to try to put a ball hinge on it so it will be more agile. I am going to ace and radio shack today to get some more parts for the launcher. I will post more pics soon.
After thinking about it I am probably just going to get the model rockets to use once and have them as displays. I would like to get some jupiter rocket fire works. The kind that have 25 small missiles in a box and just use that to have fun with. It would be cheaper to. I know a place that sells them year round. I just have to design the remote ignition. It should not be that hard to build though. I am probably just going to use the battery fuses from the model rockets.
I only made the goggles comment for humorous value. I did not suggest that simply wearing goggles would protect from a runaway model rocket. Use commom sense and keep your distance, don’t shoot anything flammable, and bring a fire extingusisher with you. Ideally, take it out to a lakefront park to fire it. Use common sense. it can be done safely.
I just noticed, though, that as it stands your rear camera will be positioned directly behind the rocket…
I am going to make a platform that will be about 3 inches from the camera and I am going to install a heat shield to protect the gears. I might just build a box around the rockets. But this is just going to be a prototype. It will evolve over time.
When the equipment being used is fundamentally unpredicatable (not designed for use in human safety situations) there is simply no way you can safely use it in the way the RK has described.
You simply can not exert positive control over Vex equipment at all times, nor can you be assured that the compiled software in it is free from errors. It is unpredictable.
RK plans to attach a dangerous rocket to an unpredictable launch platform.
I have to agree with Blake here. Folks seem to commonly believe that something can be considered safe just because it doesn’t fail often. Even if the rocket launcher performs perfectly with no accidents, that doesn’t make it safe. Tailgating at high speed is not safe, even if you don’t crash (this time).
The advice I always give regarding projects like this is: Assume that the rocket will go off at any random time while the system is powered up, and be prepared for any such random firing. Don’t assume that because it has worked perfectly for X hours already that it will continue working perfectly.
If somebody is injured as a result of operating an unsafe system like this, that isn’t an accident, it is negligence.
I agree that there is no way to cut out all possibility of injury for an imperfect system like this. That does not mean anything bad will happen, but if you follow Murphy’s law and prepare for the worst, you can still do this project. The worst case scenario here (assuming you don’t point it at anything flammable) is someone getting hit and burned by the rocket. There is acceptable risk with almost any Vex-related project you undertake and it remain acceptable as long as you take appropriate precautions to prevent it.
Right. Reasonable people do dangerous things everyday (Soldiers, Firemen, Mythbusters,…). They spend a great deal of time and energy preparing before they put themselves in harms way. That doesn’t make what they do safe, but it does help keep them as safe as possible under the circumstances.
As long as this type of project is approached with a similar mindset, then the risk can be managed, though not eliminated. It is critical that anybody trying something like this not confuse good luck with safety. They need to spend the time to think about all the ways their design could fail, and make sure they have plans to deal will all possible outcomes.
On the face of it, planning to launch Estes/Centuri rockets from a Vex Launch pad that is purposefully made mobile is the precise opposite of taking precautions.
Instead it is an example of purposefully increasing risk significantly without accomplishing any useful purpose that might compensate for the increased risk.
For some people the pure enjoyment of the task is worth the risk. My 90hp 100mph+ Suzuki gsxr600 powered hand welded racing go-kart is certainly more dangerous than a couple of model rocket motors being launched off a robot. I’m sure he will do what he feels most effectively reduces the risk of the project as i wear an up to date SNELL helmet and fireproof suit when I’m driving. There is a line between calculated risk and blatant disregard for safety, and i do not feel that this crosses that line.
If you’re careful with it, you’ll be fine. But for the love of God, fire it outside!