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Figure I would start a build thread for the 2 different tanks/robots that are being built on pirate. Should be a interesting cluster of a thread with a ton of info.

I've started to collected items to design the robot to the parts I can find for cheap and machine on the mill. So far I have recieved in the SK500 rubber tracks from ebay and electric wheelchair motors will be in Thursday.

Track info
~7in wide
.9in thick
roughly 108in in length



Wheelchair motors
Quantum Q6 Edge motors
Continuous 350Watts
Peak power 1000 Watts





dethmachinefab
Do you have info on your sprocket and where you found the idler wheels?

So far I'm trying to decided between a 12 or 14in Drive wheel?




.
 

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Idlers were cut from 5' sch 40 pipe with cnc plasma cut disks welded in, a 1.5" x.25 tube center hub joining both inner and outer wheels. The hub will recieve bronze bushings. Its an annoying job making them and keeping everything straight. They are ok, but ill build a real jig next time.

The sprocket was a bunch of guess work but ive got the mock up pretty close, i will burn the real ones from some 1/2" plate. Hard to figure out the pitch circle and flat driving lugs of the rubber track vs a standard roller chain.
 

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Here is the speed control I'm using. I've run them before and they are a great unit, from a company who stands behind their product. I had one on another vehicle arc into magic smoke and they sent a new one right away.

Lots of different control options and regen braking. Real easy to use and set up.
 

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awesome :smokin:

just remember, no matter how mundane the detail, take a picture and post some notes about it :grinpimp:
 

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have you considered how you're actually going to do the radio mixing to control the speed controllers?

pixhawk/ardupilot has a tracked vhicle installation called rover that can do all your mixing +autonomy.


hit me up when you get to radio programming.
 

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have you considered how you're actually going to do the radio mixing to control the speed controllers?

pixhawk/ardupilot has a tracked vhicle installation called rover that can do all your mixing +autonomy.


hit me up when you get to radio programming.
The sabertooth can be controlled by analog input 0-5v, r/c from a standard reciever, simplified serial, and packetized serial. I think I will start with an aircraft transmitter and reciever to get it rolling and then play with some more complex stuff. The motors are capable of running encoders so I may be able to program some neat features.
 

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Discussion Starter #9
Idlers were cut from 5' sch 40 pipe with cnc plasma cut disks welded in, a 1.5" x.25 tube center hub joining both inner and outer wheels. The hub will recieve bronze bushings. Its an annoying job making them and keeping everything straight. They are ok, but ill build a real jig next time.

The sprocket was a bunch of guess work but ive got the mock up pretty close, i will burn the real ones from some 1/2" plate. Hard to figure out the pitch circle and flat driving lugs of the rubber track vs a standard roller chain.
I think I have a working CAD model for the drive sprocket but I will be sticking some cardboad in the CNC mill and tracing one out with a sharpie. Might look funny playing with a cardboard wheel inside the track.

Here is the speed control I'm using. I've run them before and they are a great unit, from a company who stands behind their product. I had one on another vehicle arc into magic smoke and they sent a new one right away.

Lots of different control options and regen braking. Real easy to use and set up.
Yep. Same model I was looking into. Shame they cost $189 dollars.

have you considered how you're actually going to do the radio mixing to control the speed controllers?

pixhawk/ardupilot has a tracked vhicle installation called rover that can do all your mixing +autonomy.


hit me up when you get to radio programming.
Going to need to look into this a little more. A few friends recommended the Jumper T16 pro controller.
 

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Did a little work on the drive sprocket yesterday. Sure do miss having free access to a waterjet and a 2500watt CO2 laser cutter but a sharpie inside the mill will have to do. Plus I sold my plasma last year which sucks also.

The sprocket I would like to keep less than a 12x12 square so I can purchase chucks of material from ebay or other sites. Today I need to look up the formula for generating a sprocket based off diameter of sprocket and spacing since this one had spacing issues once wrapped.

Sharpie fits perfectly in a 7/16 collet.
 

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Did a little work on the drive sprocket yesterday. Sure do miss having free access to a waterjet and a 2500watt CO2 laser cutter but a sharpie inside the mill will have to do. Plus I sold my plasma last year which sucks also.

The sprocket I would like to keep less than a 12x12 square so I can purchase chucks of material from ebay or other sites. Today I need to look up the formula for generating a sprocket based off diameter of sprocket and spacing since this one had spacing issues once wrapped.

Sharpie fits perfectly in a 7/16 collet.
I had a similar issue. It took a bunch of mock ups to get close. Mine is 11" tooth to tooth. To me looks like you need more of a pointed tooth. The first sprocket I ran through my program was all wrong because it's designed for roller chain. The rubber track sprockets follow different parameters because they are linked flat bars.
 

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Did a little work on the drive sprocket yesterday. Sure do miss having free access to a waterjet and a 2500watt CO2 laser cutter but a sharpie inside the mill will have to do. Plus I sold my plasma last year which sucks also.

The sprocket I would like to keep less than a 12x12 square so I can purchase chucks of material from ebay or other sites. Today I need to look up the formula for generating a sprocket based off diameter of sprocket and spacing since this one had spacing issues once wrapped.

Sharpie fits perfectly in a 7/16 collet.
Yeah waterjet or laser would be fast but don't go crying in front of me when you have access to a CNC mill... Just order a piece of 1" plate, 1/2" -4-flute roughing mill, and 4 flute finishing mill.

Set your program to do a roughing cut .01 off finished dims(on 1" plate that's probably doable in 4-6 passes) and then 2 full depth passes to finished
 

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Where do the tracks come from?

I have been wanting to build a remote control, gas powered, hydraulic driven tracked string mower to mow hillsides on my property.
 

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Where do the tracks come from?

I have been wanting to build a remote control, gas powered, hydraulic driven tracked string mower to mow hillsides on my property.
Ditch witch sk500, bobcat mt52, etc wall behind skid steer machines. They go for about 200 each.

Variable piston pumps and hyd motors can be found pretty cheap on surplus center for your idea. I have a done a bunch of hydro drive stuff with them.
 

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Going to need to look into this a little more. A few friends recommended the Jumper T16 pro controller.
that looks nice.

I haven't radio shopped since I bought my taranis that runs the same opentx firmware.

opentx is fantastic.

that would allow you to do the mixing needed to control the ESCs, but what I'm talking about is an onboard controller with it's own GPS and the like.

there's also a bunch of autonomy things you can integrate at that poin. like ultrasonic ranging for obstacle avoidance, cameras that can recognize objects, advanced telemetry.

all the nerd shit.
 

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Discussion Starter #16
Yeah waterjet or laser would be fast but don't go crying in front of me when you have access to a CNC mill... Just order a piece of 1" plate, 1/2" -4-flute roughing mill, and 4 flute finishing mill.

Set your program to do a roughing cut .01 off finished dims(on 1" plate that's probably doable in 4-6 passes) and then 2 full depth passes to finished
Machining it should be easy. I might need to buy some more endmills since most are for AL right now.

I had a similar issue. It took a bunch of mock ups to get close. Mine is 11" tooth to tooth. To me looks like you need more of a pointed tooth. The first sprocket I ran through my program was all wrong because it's designed for roller chain. The rubber track sprockets follow different parameters because they are linked flat bars.
I think I finally have the pattern down. Was tempting to just order the drive sprocket for 74 each but unsure yet if I will.

that looks nice.

I haven't radio shopped since I bought my taranis that runs the same opentx firmware.

opentx is fantastic.

that would allow you to do the mixing needed to control the ESCs, but what I'm talking about is an onboard controller with it's own GPS and the like.

there's also a bunch of autonomy things you can integrate at that poin. like ultrasonic ranging for obstacle avoidance, cameras that can recognize objects, advanced telemetry.

all the nerd shit.
I do need to watch how automated I make the system due to gun laws.
 

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Machining it should be easy. I might need to buy some more endmills since most are for AL right now.



I think I finally have the pattern down. Was tempting to just order the drive sprocket for 74 each but unsure yet if I will.



I do need to watch how automated I make the system due to gun laws.
If someone cared to restrict their freedoms, what would they need to be concerned with?

Got my bearings and idler bushings today. Been too busy with work to get anything done though.
 

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If someone cared to restrict their freedoms, what would they need to be concerned with?

Got my bearings and idler bushings today. Been too busy with work to get anything done though.
ATF doesnt look to kindly to automated guns without being a 3 letter agency. Similar to being illegal to build a full auto firearm without a SOT, and paperwork.

Received in the wheelchair motors today. Looking dam good.
 
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