Oh no. Please no.
Only the dead can know peace from these puns.
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Oh no. Please no.
Only the dead can know peace from these puns.
Hog ox roast in a few months :)
Jamie: no more messing about in Jay's asstronomical build thread.
Ahem,
Now that's out of my system, I plugged all the known design elements into the EDT simulator and got these results:
http://www.nswrfc.org/Nick/Hard-ox_1.jpg
This assumes 150mm wheels, 8:1 gearing, 24V with 'unlimited' current capacity and the full 110Kg weight limit. I used a Bosch 750 motor as I don't know which Movimotor is being considered - I hear its lower RPM, so maybe the gear ratio needs changing to get a decent speed. Hope this helps and if I can get more motor info, I can make the figures more accurate.
EDIT: Just saw the model number in another thread - with a 3,300 RPM speed at 24V, lower gearing might be advisable.
So less teeth on the drive wheel?
Would different size wheels make a difference?
I would personally go for larger wheels rather than a smaller sprocket; you will get a larger contact patch on the arena floor and hopefully better grip with a larger wheel. What is your target speed and I can plug that into the simulator to work out a wheel size?
Ive not really thought about speed, good acceleration, 15+ mph seems a good figure.Quote:
Originally Posted by overkill
Was going to be a trail and error type procedure ha...
OK, with the first set-up the theoretical top speed is only 7.1 MPH. If you double the wheel size or halve the reduction then the bot should top out at around 14MPH. The problem with that is the maximum tractive current (the current when the wheels just start to spin) increases to 230 amps. That's for both motors but half of that is still way more than the average current capability of the Roboteq, so its going to get quite toasty!
Just to give a real world example.
Bullfrog uses Iskra 24V 1.2Kw 3100rmp motors, on 10S LiPo. Gearratio 20 to 1 with custom mod 1 gears -wider than standard- and a Foam wheel like Sewer Snake uses.
Top speed theoretical 11km/h. But it reaches it instantly and as an added benefit, we can use a Sidewinder as the current draw is low.
you run a 12v motor on 37v? How many of them do you get trough?
Sorry, typo. Is 24V
I now have castors, wheels, drivetrain, a speed controller & a set BOSCH 750 motors!!
PROGRESS!!
Good going any update pic's?
awesome, cant wait for next set of pics!
Houston, we have a problem!!
So, i was hoping the new drive setup would slot right in... Yea that didn't quite go to plan lol...
Attachment 5698
I fear your Hard-Ox will get a wider ass.
Not a bad thing in itself, a wider wheelbase makes a better controlable machine.
But if you want to use it like that, narrower wheels?
Quote:
Originally Posted by maddox10
It dont look like it, but its only 20mm too wide, so i might be able to chop the wheel hubs down and shorten the axel.
Those motors do not look secure at the end of those thin supports. Can you not bring the motor closer to those side plates and reuse the width of the whole drive? Its a bit of work but will mean the shell would fit.
Customizing hubs, with a decent lathe no prob.
But as I wrote earlier, and especialy with the length in mind and a painfull horizontal disk in front, a wider wheelbase isn't a bad idea.
Im still not 100% sure on the weapons, im toying with a couple of ideasQuote:
Originally Posted by maddox10
It appears my guesstimation on the weight was out... Slightly haha..
Anyone fancy a guess?!
If you used 3.2mm Hardox 450, and my guestimate of the size is correct, it's 35 kg for the shell alone, at least.
With the box section you did show as internal bracing, it's 45 kg , without anything in there.
This looks amazing!!!! Great work!
Your'e a wise man!Quote:
Originally Posted by maddox10
It came to a total of 39.3kg!
So i got this through today from active-robots, no instructions, no cd? or extras cable as all offerd by RoboteQ official site..
Im still not 100% on speed controllers, so do i need the cd and extra cables for the 2 Bosch motors?
Attachment 5711
Just a guestimate on size. You're building large.
On esc. I think you can download everything from the Roboteq site.
download manual
they are quite easy to use if you need any help I might be able to talk you thought it or pop by if needed
pm if you need any extra help
No worries, as for cables for the Bosch motors?
I got mine today too. The motor cables are there already, you need the cable to connect the controller to the RC. You need to buy that separately from active robots.
Ah man, for that price you'd have thought they would have included that -_-Quote:
Originally Posted by supernova
Depending upon the model you will have 8 large cables in sets 4, one positive one negative one motor feed out one motor feed return per side
Rc input cable is available separate or you can make one manual shows which pins you need to use
My advice by plenty of 50amp Anderson connectors and a few 175
Will make removing and testing much easier if you use quick release connectors
Always mount on vibration mounts if possible. Heavy shocking kills escs quickly
EC5/XT90 or even EC3/XT60 to connect the ESC to the motors.
After all, the peak loads are nothing more than that, peak loads. Of course, that is for the low end motors.
For stronger motors, doubling up is a suitable plan. After all, 1 Anderson is more expensive, larger, heavier and a lot more vurnable to self removing than 2 of the other mentioned connectors.
I have bought a load of XT90s, will be soldering up tonight.
Would you use them as the connector to the LiPo pack with a burst current of 500A? There is a 500A fuse in line also.
Little confused why there are two sets of battery wires to the roboteq, guess doubling up on cables improves current handling.
I don't see why not?
One step forward.. Three steps back... Lol
Decided it'd be easier and quicker to chop it's head off, run a slitter through its belly, spread it, then re plate and weld..
saves making a new drive set-up!
Attachment 5712
Hey peeps,
Sorry the thread has gone a little quiet.
We've had a very upsetting and emotional week at work, a fellow work colleague fell from an overhead crane and sadly passed away on site.
The build has naturally taken a back seat for the time being, as there has been absolutely no access to the area.
Hey peeps,
Good news... Work has continued on "The Un-Named Robot" <lol..
So.... The plan is to mount the drive to a sheet of Hardox, then have it removable with 8 high grade bolts.
Attachment 5812
The drive system mounted to the removable plate,
Next step is to mark out where is gonna sit, remove the two side plates, then weld them into the robot shell :)
Attachment 5813