Author Topic: Bruder Manitou 2150 - RC conversion  (Read 13007 times)

Offline ddmckee54

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Re: Bruder Manitou 2150 - RC conversion
« Reply #75 on: July 10, 2020, 03:35:07 PM »
I'm trying to find a 1.75mm PLA filament that's a close color match to the plastic Bruder uses in their injection molding.  I'm going to post this on a couple of different forums and hope for the best.

I've been trying to find a close match to the red they use for my Manitou 2150 RC conversion. I've found a lot that aren't red enough, I've got three or four 1Kg spools of various shades of red to use up now. I bought a spool of what was claimed to be the REDDEST red available - it's called Enzo red. Looked great on the screen, in real life on the spool - not so much!(Couldn't tell the difference between the Enzo red and the bargain basement Solid red.) I found that E-Sun's Fire Engine Red is TOOOOO red, it needs a little yellow. But, it's close enough I can live with it if I have to.

I got the Manitou 2150 at a bargain price, but it was missing few pieces - among the missing was a fender. The only replacement piece I couldn't get from Bruder was the fender, so I printed all four fenders in the grey that I had. The grey that I've got is a little too light, but it also is close enough that I can live with it.

I've got models on the shelf waiting for future conversion where I'll need the yellow that they use for their CAT models and their Liebherr models. Who knows, there might even be a need for a John Deere green in the future. (Even though I was raised on IH red and Ford blue.)

So, anybody know of any close filament matches in PLA? I'm not set up tp do ABS, and I don't want to have to deal with the smell in my living room where the printers are.

Don
Too many irons, not enough fire.

Offline ddmckee54

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Re: Bruder Manitou 2150 - RC conversion
« Reply #76 on: August 03, 2020, 11:43:29 AM »
Nothing of interest accomplished in the last few weeks.  I did order yet another spool of Red from e-sun, it's not a close match to the Bruder red plastic either.  I'm gonna call the e-sun fire engine red close enough even if it is too dark of a red.  I've been gathering parts to put the steering linkages together.  What a comedy of errors, MOSTLY my errors. 

I ordered a bunch of M2 ball links for the steering.  You'd think that would mean that it would be threaded for an M2 threaded rod wouldn't you?  I know that's what I thought, so I ordered an M2 tap and die so I could thread the ends of the tie rods.  I  ordered them from a US supplier so that I would not have to wait weeks for the shipping.   I apparently didn't pay enough attention to what I was doing when I ordered the tap and die set, because I ordered a LH tap and die.  I then ordered a RH M2 tap and die set, and had to wait another week for it to arrive.  By this time the ball links had arrived and I found out that while the ball is drilled to fit an M2 bolt, the link itself was un-threaded.  Not only was it un-threaded, it's ID is molded in the correct tapping diameter of an M2.5 tap.  So I ordered an M2.5 RH tap and die set and some 2.5mm rod.

On the bright side, IF in the future I EVER need to make M2 turnbuckles, I'm all set up.

I've kept the printer busy cranking out parts for a CNC router I'm designing.  I've got over half of the parts that I need to print completed.  The total printing time for the parts is about 153 hours and I have about 121 hours of that printed.  If I don't have a mess when I get home that will go to 131 hours of printed parts.  When I get all the parts printed that will be another build thread.

Don
Too many irons, not enough fire.

Offline ddmckee54

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Re: Bruder Manitou 2150 - RC conversion
« Reply #77 on: September 23, 2020, 11:48:54 AM »
I've been taking a break from the Manitou for a while.  I built one of these, a photoetech kit of a Gatling gun, see the 1st attachment.  This is not a picture of mine, it's a stock photo of the model.  Mine isn't quite that good, but it's close.

Now I'm working on the cutaway model of the Allison 501-D13 turbo-prop, see the 2nd attachment.  The military version of this engine it the T56 which just happens to power the C130 Hercules, my favorite cargo aircraft.

Next on the hit parade will be the little jewel that's in the 3rd attachment, a 1/3 scale visible model of the Ford 289.  I build one of the Revell Visible V-8 kits when I was a kid.  I think I saved my money for most of a year to buy that kit.  I actually got it to work which is something of a surprise since I was probably about 12 at the time.  I looked into the new version of the Revell V-8 but wasn't impressed, since it's no longer motorized.  Besides I believe the Revell Visible V-8 is based on a GM engine, the 283 I think?  I'm a Ford guy, so the 289 being Ford blue sealed the deal.

I'll get back to the Manitou when I've got this modeling phase out of my system for a while.

Don
Too many irons, not enough fire.

Offline ddmckee54

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Re: Bruder Manitou 2150 - RC conversion
« Reply #78 on: July 23, 2021, 02:26:31 PM »
This project isn't dead, but is is definitely off the back burner and probably even off the stove.  The bigggest problem that I had with it was the number of channels that leveling the crane properly would require.  I had come up with a work-around, but I was never really happy with it.

I recently stumbled across the work that Mick thebass has done on his YouTube channel.  https://www.youtube.com/channel/UCbTqmHlFmasSVFomeuu0hsQ/featured   Check out his Asua dumper and CAT telehandler builds.  The man is a genius when it comes to putting 10 pounds into a 5 pound sack, AND working with Arduinos.  Since I've already got an Arduino Nano running the lights for the Manitou, at least on a breadboard, it wasn't much of a leap to start thinking about making it do more.

I've dived down the Arduino rabbit hole once again and from the research I've done, I know that having the Arduino control the servos is ALMOST dead easy.  Using the Arduino as the receiver and controlling the servos and lights are the easy parts.  I think with a few bucks worth of sensors it should be entirely possible to have the Arduino control the leveling sequence.  They are already being used in projects for autonomous control of drones.  I don't need active 3 axis control, all I need is slow speed control of the roll and pitch axis.  Yaw doesn't really matter when your vehicle is firmly planted on the ground.

I've ordered a couple of rolls of red filament that should closely match the Bruder red.  At least I think I have, but nothing has shown up yet.  I'll need to check the credit card statements to see if I need to start yelling at somebody to find out where my filament is.  Or maybe make a doctor appointment about my memory?  AHH... I'm sure it'll be fine.

Don
Too many irons, not enough fire.

Offline ddmckee54

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Re: Bruder Manitou 2150 - RC conversion
« Reply #79 on: September 15, 2021, 04:35:13 PM »
OK, no pictures but I do have an update.

I found several examples on the Worldy-Wide-Web illustrating how to make an Arduino level using a 6050 IMU sensor, or at least how to get the pitch and roll angles.  Most of the examples are aimed at making autonomous quad-copters using an Arduino so they need to worry about high-speed responses, dealing with propellor vibration, and gyro drift.  None of those are going to be a worry for me since this is a crane with it's feet planted firmly on the ground - figuritively speaking.  ALL movements will be SLOW and at a known rate so the gyro isn't really needed.  There will be some vibration as the leveling feet are being lowered, but since I'm only dealing with one foot at a time that should be minimal.  The gyro was used to help deal with the vibration effects on the 6050.

With the pitch and roll angles it's a short step to auto-leveling a crane.  Last night I started out-lining how to have an Arduino auto-level a crane on command.  I also ordered a bunch of parts so that I could get the system working on a breadboard.

Now I've got to find the red, grey, and black filaments and print up a bunch of parts to build a mock-up.  Then machine some parts to turn the gearboxes into linear actuators, and test all that crap.  Then rinse, lather and repeat, if/when those parts fail.  Gotta be able to test this and get all the bugs worked out before installation.

Don
Too many irons, not enough fire.

Offline ddmckee54

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Re: Bruder Manitou 2150 - RC conversion
« Reply #80 on: September 23, 2021, 12:16:39 PM »
Well, Ive got good news and bad news.

The good news is that all the parts have come in so I can start experimenting with the 6050 IMU and my Nano clone, to see if I can work out an auto leveling system for the Manitou.

The bad news is that last night I did some drawing to determine how much of a pitch and roll angle the crane could be at and I would be able to level it using the outriggers with no blocking.  Turns out its not so much.   Ive attached a JPG of the 3D PDF since some people seem to not be able to view the PDF.   
 


In its current configuration the outrigger pad, circled in brown, will extend about another 3 to the right, actually 77mm for those of you that are Imperially challenged.  The outrigger will pivot around the location circled in blue.  The outrigger assembly is driven up and down by the ram, the yellow part right above the outrigger.  The ram will have about 3/4 of travel, call it 20mm.  This translates to about a 1-1/4, call it 30mm, vertical travel of the leveling pad.  In itself, this is not bad.  However theres almost 1 of ground clearance to the leveling pad, call it 24-25mm, so theres less that 1/4 of actual vertical movement before the ram reaches the end of its stroke.  Im going to have to either use blocks almost all the time, or I need to redesign the outrigger rams.

I think Ive got 3 options on the redesign:
1) Raise the ram motors a lot maybe 20-25mm!  I dont know if Ive got room to do this and still clear the molded in counterweight.

2) Move the ram motor assembly from centered on the outrigger to the far side of the outrigger.  The far side would be away from the 2 outriggers.  This would allow me to move the point where the ram attaches to the outrigger from the top of the outrigger to the bottom.  This would give me approximately an additional 20mm of ram travel.  The additional ram travel would give me an additional 30mm of vertical travel on the pad.  The problem with this option is Im not sure Ive got enough clearance between the wheel and the outrigger for the ram.

3) Move the ram motor assembly from centered on the outrigger to the inside of the outriggers.  The inside would be between the 2 outriggers.  The problem with this option is Im not sure where the ram would be in relation to the outrigger extension motor.

If I can get another 20mm of ram travel, that translates to 30mm of vertical movement for the leveling pad at full extension.  I could lower the leveling pad about 1-1/2".  Which if I measured it right means I would be able to correct for a +/-13 roll angle and/or a +/-9 pitch angle on the crane.

Don
Too many irons, not enough fire.

Offline WeldingRod

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Re: Bruder Manitou 2150 - RC conversion
« Reply #81 on: September 23, 2021, 12:27:42 PM »
Move the blue circled pivot point inward?

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Offline ddmckee54

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Re: Bruder Manitou 2150 - RC conversion
« Reply #82 on: September 23, 2021, 12:54:36 PM »
WeldingRod:

That might help, what might help more is dropping the outriggers down so that they're even with the bottom of the axles.  This would move the pivot down not in.  That would effectively give me 10-12mm more of vertical travel just by eliminating some of the ground clearance under the outriggers.  But it wouldn't be eliminating any of the crane's ground clearance since the axles are that low already.  When you add in the additional 10-12mm of ram stroke that would give me I'm probably close to the 1-1/2" movement that redesigning the ram placement would have given me - with a lot less hassle.

It's a change from the Bruder original, but they were designed as toys - not scale models.  I can live with it.
Don
Too many irons, not enough fire.

Offline ddmckee54

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Re: Bruder Manitou 2150 - RC conversion
« Reply #83 on: September 24, 2021, 01:54:56 PM »
I looked at the model last night, both the 3D version and physical one, and I came to the conclusion that my options 1-3 will NOT work.  I can't raise the outrigger ram motor, option 1, because that will interfere with the crane counterweight as it swings around.  I can move the rams to what I called the outside, option 2, because that will interfere with the fenders and wheels.  And I can't move the rams to the inside, option 3, because that will interfere with the outrigger extension motor.

WeldingRod suggested moving the outrigger pivot point in, and I thought about that, but I wasn't sure if that would be a help or a hinderance.  It did get me to thinking about moving things though.  Last night I played worked with the 3D model and lowered the outriggers 11mm so that the bottom of the outrigger was even with the bottom of the axle. 
That way I can accomplish several things.  I don't lose any ground clearance on the model, I reduce the amount of travel between the UP position of the outrigger and the ground, and I extend the outrigger ram - giving me more travel on the ram.  I'm gonna give WeldingRod the blame credit for this idea.  I've attached a screenshot of the revised 3D model.  Ignore all the extra crap - I forgot to turn it off before I saved the PDF last night.
 

The second attachment is a HIGHLY simplified front view of the Manitou.  Cant see it?  Well, at least all the important bits are there anyway.  The white rectangle at the top is the upper frame of the crane.  Below the upper frame is the outrigger, it is shown in with the outrigger fully extended,  The horizontal line that runs all the way across from one side of the screen to the other is the level ground.  The vertical line on the left is the outside of the tires on that side.
 

Inside the orange blobby-circly-thingy is the outrigger pivot point, this point never moves with respect to the upper frame.

Inside the magenta blobby-circly-thingy is the outrigger ram lower pivot point when the ram is retracted, the angled white line is the ram centerline when retracted.  The small white circle to the upper-left of the magenta thing is the outrigger ram upper pivot point this point never moves with respect to the upper frame.  The green circle shows the path the end of the outrigger ram would follow as it is swung around the rams upper pivot point.  The cyan circle shows the path that the rams lower pivot point will follow at the outrigger is swung around its pivot point.  The white line, the green circle, and the cyan circle all conveniently intersect at the same spot, the fully retracted position of the ram.

I determined that the outrigger ram has 27mm of usable travel.  Offsetting the green circle 27mm. and I get the red circle.  The stuff shown in green is with the ram fully retracted.  The stuff in red is with the ram fully extended.

The tan blobbish thing on the right contains the simplified outrigger pad, thats the green inverted T, the pad pivot point, and line that shows the center-to-center distance between the pad pivot point and the outrigger pivot point.  The large white circle is the path the pad pivot point will follow as the outrigger ram extends and retracts.  All this crap just to get a couple of angles, and were still not done.

Where the red circle and the cyan circle intersect will be the position of the outrigger ram lower pivot point when the ram is fully extended.  Looking at this in the light of day I can see I made as boo-boo  19.6 does NOT equal 19.21.  I think I know where I screwed up, when I changed the angular dimension style halfway thru the drawing - I changed it from X to X.XX.  I measured the angle between the two green lines so I could determine where the pad pivot point would be with the ram extended.  It measured 5, but it was actually 5.39 - I just measured it.  That means my measured maximum pitch&roll angles will slightly too small, probably by less than - degree.

OK focus!  Back to draining the swamp.  With the pad pivot points lowest position now fixed we can find where the pad touches the ground, the red inverted T.

Assuming that the crane will pivot on the outside of the tire, we draw a line from that point to the pads assumed contact point and measure the angle.  VIOLA, we get 9.11-ish, remember I makada slight boo-boo way-back-when.  Thats the maximum roll angle I can hope to correct without blocks.  The vertical line on the right represents the distance between the front and rear outriggers.  When I connect the dots and measure the angle I get 7-ish degrees as the maximum pitch angle that Ill be able to correct without blocks.

I actually thought it would be more, but numbers dont lie.

Don
Too many irons, not enough fire.

Offline ddmckee54

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Re: Bruder Manitou 2150 - RC conversion
« Reply #84 on: October 07, 2021, 05:43:48 PM »
I was looking through this thread from the beginning, and WAAAAYYY back in Post#9 I found that WeldingRod had suggested this...

You could set the legs up to go to fixed positions one at a time.  Or, if your insanity knob is broken off, you could make it self leveling ;-)

WeldingRod are you physic or sumfin?  I think the insanity knob has been turned way past 10 to maybe 15, or 25. 

The current plan is for the Arduino to extend/retract, raise/lower the outriggers.  To do this without breaking anything I'll need at least a fully retracted limit switch for outrigger extension.  I think I can get by with just timing the extend,  I'll just have to find the maximum safe extension time.  I'll use the fully retracted limit switch so that the outrigger will always be starting its' extension from a known position.  I'll need a full up limit and a full down limit for the outrigger raise/lower ram so I don't break anything on it.  That's 3 limit switches per outrigger or 12 total for all the outriggers.  When you add in the I/O for the lights and communicating with the radio this is WAAAAYYY beyond an Arduino Nano, probably need to go with a Mega.

I'll start the auto leveling sequence by leveling the back of the machine.  I was going to start at the lowest corner, but then I realized the rear axle is fixed, while the front axle pivots.  If the lowest corner is at the front of the machine and I try to correct the roll angle, then the machine has to pivot on ONE of the rear tires - putting a lot of stress on things.  I know, this is a MODEL and the stress will be minimal - but still...  Anyhew, lower the high side rear outrigger until the roll angle changes, then lower the low side rear outrigger until the roll angle changes.  At that point both the rear outrigger pads are on the ground.  Continue to lower the low side outrigger until the roll angle is 0 or at least crose-enuf, or until we hit the outrigger max down limit - which-ever comes first.  The low side outrigger will also need to be slowly extended as it is being lowered to keep the pad in approximately the same spot.  The end of the outrigger swings in arc as it is lowered which will try to pull the pad closer to the machine - can't have that.   (We gots an Arduino, it can keep track of such trivia so we don't have to worry about it.)

Next we lower the front outriggers until they touch the ground.  I was planning on lowering one at a time until I saw a change in the roll angle, but with both the rear outriggers planted firmly on the ground I don't think it's going to want to roll much, won't know until I get a test rig built.  It'll probably be best to look for a slight change in pitch angle, the outrigger will be lifting the machine after all.   Do this for both sides up front.

Once both front outriggers are on the ground we determine from the pitch angle if we're nose up or nose down.  If we're nose up then lower and extend both of the rear outriggers until the pitch angle is crose-enuf to 0.  If we're nose down, then do that to the front outriggers instead.  We may have to do some correction to the roll angle as we are correcting the pitch angle, but that's for later when we decide to get elegant with this instead of just hitting it with a 2x4 to make it work.  Same for alerting the operator that it's too far out of whack to do an auto-level without some help.

I need to do some more digging into the 6050 IMU that I'll be using for the pitch and roll sensor.  I need to find out when it initializes, whether it's on power-up, or if it's on command.  I think that the pitch, roll, and yaw angle offsets are determined on initialization - and all angles are based on those offsets.  I seem to remember one video where the unit was initialized and then yawed 90, the IMU was showing what was actually a pitch angle as a roll angle, and vice-versa.  If it initializes on command then I'm golden as I intend to keep this thing brain-dead until I tell it to level.  If it initializes on power-up then I'll have to do what the quad-copter guys do and correct the pitch and roll angles based on the yaw angle.

Meanwhile back at the ranch, I need to figure out what I'm going to use for limit switches, and where I'm going find room to put them.  I'm going to need to get plenty of inspirsation from Mick thebass, and the rctractorguy.  Mick does Bruder conversions, check out his YouTube channel. https://www.youtube.com/channel/UCbTqmHlFmasSVFomeuu0hsQ  He has no problems putting 10 pounds into a 5 pound sack. 

The rctractorguy converts 1/32 scale die-cast tractors and equipment to RC, and that's more like putting 25 pounds in a 5 pound sack.  This is his channel.https://www.youtube.com/c/rctractorguy

I wanna be just like those guys when I grow up, right down to the cool accents.
Don

I know, I know,,,  No pictures so this didn't really happen, but there's been a LOT of skull-sweat involved, does that count?
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Offline jiihoo

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Re: Bruder Manitou 2150 - RC conversion
« Reply #85 on: October 08, 2021, 07:53:54 AM »
For the outrigger limit switches, could you get by connecting all the limit switches of one outrigger in series and only using one Arduino input for the three of them?

Since the Arduino already knows (approximately) where in the range the outrigger is and in what direction it is moving, it should be able to deduce which of the three limit switches was hit. This does require some minor housekeeping in the software, but if it prevents the need for a Mega it might well be worthwhile.

The tricky situation would be if the SW crashed and needed to restart or if it would be starting up after an improper shutdown and any of the limit switches was active at that time. In this case it would need to halt and you'd manually have to solve the situation... In normal operation it would always need to back away from a limit switch right after hitting it: i.e. when retracting and hitting the limit switch the motor would need to spin the other direction for a short while to de-activate the limit switch before parking the outrigger; the same when leveling up or down.

You have a nice project going here!

Offline ddmckee54

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Re: Bruder Manitou 2150 - RC conversion
« Reply #86 on: October 08, 2021, 12:52:55 PM »
jiihoo:

You might be onto something there.  I can see a couple of problems with that, but they can be solved.

1) What if the unit gets powered down with the outriggers not "Homed" - fully raised and fully retracted?  I can see a couple of solutions:
a - If the Arduino has non-volatile memory that can be accessed, store a Direction bit for each outrigger's extension/retraction and raise/lower.  I'd planned on using these direction bits anyway, so the Arduino will know what it's supposed to do when it sees a limit.
b - Probably the simplest solution would be to have a routine that will Home the outriggers on power-up - similar to what you suggested.

2) Second potential problem I can see with a single input would be during the outrigger raising/retracting cycle.  If I raise and rectact at the same time, I could potentially hit both limits at the same time.  I can see a couple of ways around this problem.
a - Completely the cycle on one of these, then do the other.  This is the simplest solution, but the slowest.
b - I can see a way to retract and raise the outriggger at the same time, and do it safely.  The outrigger extension will be single speed.  Or at worst case 2 speed, and they will move fairly slowly.  The screw is an M3x.5, the outrigger maximum extension is about 75mm, and the gearmotors run at 100rpm - it should take about 1-1/2 minutes to go from fully extended to fully retracted at full speed.  The minor houskeeping in the software that you mention will be keeping track of the time from fully retracted until the pad touches the ground.  For instance, if the outrigger extends for 55 seconds before it touches down then it would be safe to retract the outrigger for 50 seconds, while raising the outrigger at the same time.  The outrigger would then wait while the raise cycle was completed, at which time it would fully retract.  I believe that the raise/lower gearmotor runs at the same speed, will use the same thread on its' screw, and its' maximum extension is 27mm - so if the default extension if the outriggers is far enough, the raise cycle should ALWAYS complete long before the ourigger would be near the fully retracted limit.

You just saved me 9 I/O pins and maybe a bunch of wiring.  There's actually a lot uf unused volume inside this thing.  There are a lot of cross braces to keep a kid from crushing it but for the most part they can go.  Unless I do something REALLY stupid with this model I should be safe getting rid of a lot of the cross bracing.

Maybe I actually can run this thing with Nano's, in a Master/Slave setup.  I've already got a slip-ring for the rotating part of this beast and I think it's 12 circuit.(At least 6 circuit.)  That way I'd use a master to handle the communications with the radio, a slave in the rotating section, might want to use a slave in the upper main frame to handle the lights and slew motor ESC and outriggers.  The master would be in the lower frame and could also handle the steering and drive motors.  OOOOHHHH, this is gonna work out better than I thought.  Might need to go with an Uno in the upper frame - there's a lot of lights.

I've got plenty of room in the counter-weight to stash a slave controller for the rotating portion.  The rotating portion controls will consist of boom raise/lower ESC(And limit input.), boom extend/retract ESC(And limit input.), fork up/down tilt ESC(And limit unput.) a winch ESC, and a flashing beacon.

The upper frame controls will be the slew motor ESC, headlights, tail-lights, and turn signals.  To get brake-lights I need separate turn-signal outputs for each corner.  That's a minimum of 6 outputs for lights, 7 if I use hi-lo beams.  I almost forgot about the outriggers, this is where it coulld get ugly.  Using the brute force approach I'd need 8 PWM outputs for ESC's and 4 limit inputs, just for the outriggers.  Using a slightly more elegant approach and switching between the front and rear outriggers - that drops to 4 ESC's, 2 limt inputs, and at least one output to do the switching.  I've got a lot of usable volume in the in the upper frame, but not THAT much - I've still got to get a battery pack in there somewhere.

This thing is 4WD, and 4 wheel steer, can a Nano handle 4 PWM signals, left side ESC, right side ESC, front steering servo and rear steering servo?  I'm liking this, using an Arduino for this will make switching between normal steering and crab steering SOOOO easy.(With a 6 channel radio - 10 with open source upgrades - I had given up on the ability to crab steer.)

All the gearmotors, even the winch, are N20's - so even an itty-bitty 10A ESC is overkill for them.

Don
Too many irons, not enough fire.

Offline russ57

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Re: Bruder Manitou 2150 - RC conversion
« Reply #87 on: October 09, 2021, 01:34:36 AM »
https://www.ebay.com.au/itm/PCF8575-IO-Expander-Module-I2C-To-16IO-/233680411720?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l49286&mkrid=705-154756-20017-0

May help with the limit switches

-russ

(i2c expander - 16 io pins on the i2c bus for future searches when the ebay link expires...)
« Last Edit: October 10, 2021, 12:26:01 AM by russ57 »

Offline WeldingRod

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Re: Bruder Manitou 2150 - RC conversion
« Reply #88 on: October 09, 2021, 02:46:21 PM »
You could monitor/limit current on the leg motors and detect end of travel by stalling.  Maybe with something springy in there for a little reaction time ;-)

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Offline ddmckee54

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Re: Bruder Manitou 2150 - RC conversion
« Reply #89 on: October 11, 2021, 01:42:30 PM »
You could monitor/limit current on the leg motors and detect end of travel by stalling.  Maybe with something springy in there for a little reaction time ;-)
WeldingRod:

I'd thought about doing that, but all the current sensors that I could find were rated for 1-30A.

The motor info that I could find for the N20/GA12 gearmotors suggests a running current somewhere in the range of 0.04-0.1A and a stall current of somewhere between 0.2-0.67A.  I'd need a current sensor that's an order of magnitude more sensitive than what I've been able to find.

The other isssue I had with the current sensor was that I only have a hard stop in one direction of travel.  I haven't been able to figure out a way to have a hard stop in the other direction.  At least I haven't come up with a method that would be reversible when repairs are needed, and still be within my somewhat limited capability to make.

Don
Too many irons, not enough fire.

Offline WeldingRod

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Re: Bruder Manitou 2150 - RC conversion
« Reply #90 on: October 11, 2021, 02:56:03 PM »
Just use a small series resistor and measure voltage across it...  you need to make sure that the analog input can measure to the rails, though.

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