This video:

Chat:
Al’s github page:

Al’s instructions for installing a simulator:

Index:
00:00 Al: Gives a status update.
Modified some dimensions on his simulator model.
01:20 Al: Talks about path generation.
Referring to this video:
03:40 Al: Talks about his speed problem.
04:25 Discussion of velocity units.
07:20 Al: Talks about his github organization. And more comments of paths.
10:35 Jeff: Shows the crimp on wire ferrules he mentioned last week.
13:55 Jeff: Holds up a single channel Cytron board. And Terry’s grounding issue is discussed.
16:25 Jeff: Random updates on what did (or did not) do.
17:15 Terry: Talks about the communication protocol for his drill batteries.
24:05 Terry: Talks about controlling his motors with a PID function.
28:40 Terry: Asks if ROS will control accel/decel or do you have to do it yourself.
30:20 Al: Brings up processor speed for quadrature decode.
33:15 Jeff: Again brings up the concept of using a cheap Blue Pill board as a smart peripheral.
And a discussion about SAMD21 vs. SAMD51. Because Jeff was confused.
34:45 Terry: Plans to address his motor control.
Discussion of the Milwaukee drill battery.
38:40 Al: Shows his battery management software monitor.
40:30 Jeff: Asks about the battery adapter for the drill battery.
43:30 Terry: Shows a voltage convertor he ordered.
44:55 More discussion on decoding the battery protocol.
48:15 Terry: Points out where he is loading software.
He is going to put Zener diodes on his voltage dividers.
49:15 Al: Points out the obvious.
49:50 Jeff: Talks again about automatically verifying his R/C servos.

Lawn Tractor Automation YouTube page:

Index for Lawn Tractor Automation group:
http://sampson-jeff.com/RosAgriculture/LawnTractorMeetingNotes.txt

Index for the original ROS Agriculture group (~250 videos):
http://sampson-jeff.com/RosAgriculture/readme.txt
http://sampson-jeff.com/RosAgriculture/ros-agriculture-youtube20230104.txt

All right so for an update today Um Turn screen sharing on on my second Machine I've got going here bear with me It's running um gazebo and Arvis so it's A little bit slow Um I had the I still haven't fixed the speed issue And Before I tried to dig into that very Much I wanted to try to Um make sure I was working on the right Yaml files and config files and whatnot So I ended up Uh Consolidating the number of files into One Workspace that's Out here on GitHub one of the things as Well is the wheels were A little bit submerged in the ground and So I worked through Changing the origin statement in the Base footprint to I think they're Basically on the ground at the moment And I'll walk through a little bit of This workspace Here in a second Following that I'm like hey I want to Have a Consistent path that I'm testing In the simulator while I'm trying to

Work through this speed thing so I Thought I would go relearn Um how we did this path generator thing A number of months ago So at the moment Um So I got to get the 10 planner to run The vehicle at two you know plus or Minus two meters a second Path follower also I noticed uh which Would use the output of this Generator is based on move base Flex So we'll have to resolve what sort of Path follower Whether to try to change The lawn tractor to move base Flex in The simulator or try to get a different Path the followers so for me the next Thing is Maybe get the path dollar worked out so That I can follow a consistent path over And over well so it'll be a little bit Maybe more Consistent in resolving the speed and Then resolve the speed issue And then work on the low level Controller oops This uh Will be familiar to to Jeff but What's um What this is Terry is this Python program you give it a This is you know I gave it four

Waypoints or four Points and that are in this Waypoint Text file And it generates two things one this Image But more importantly it generates Oh about five or six waypoints for each Point Um And so that's what I want to run you Know consistently just to work out The Kinks and my steering and whatnot And speed control And then on the working on the speed Thing Jeff you know Uh but I've got half a dozen or so URLs to sort of investigate a couple of Them Leaned into a little bit One guy was saying hey you gotta Make sure your acceleration limits are High enough Mine are Sitting at that point 3.2 2.5 and 2.5 Although I want to make those more Consistent I'm not sure that's the That's going to do it for me but It's just a little bit of where I'm at If I go back to um What what are those velocity units I'm not sure I believe they're meters Per second but when it comes to these Limits and Theta and whatnot I'm I'm Assuming they're meters per second

And I had just put some arbitrarily High Numbers in there Hoping to get Um you know something close to that from A speed standpoint but Which what's your actual question Terry I I'm just I I'm Kind of jumping ahead to setting my PID And I'm wondering what units to set for A PID is is it revolutions per second is It distance traveled per second In in Ross as a standard all velocities Are represented in meters per second All rotational Uh velocities are radians per second Angles are in radians and distances in Meters so it's you know just Combinations of those That's what I need to know so when You're all done Ross is going to say I Want you to drive forward at half a Meter per second so you do whatever it Takes to convert that half a meter per Second request into making your vehicle Move at that speed is what it comes down To And if you if you're making a curve but You don't have a Ace um A steering as your tractor does but Rather a differential Is that go this distance at this Velocity

At this turn radius They will give you the standard way to Do it they say here's the forward speed And here's a rotational velocity so Again it's up to you to convert Rotational velocity into making a turn And the simplest way on a differential Drive you just simply say left wheel is Forward speed plus rotational velocity And left one is forward speed minus Rotational velocity and that will Convert it to the point where your two Wheels will turn the speed to do what it What it wants you to do Got it later I said you might you might Have to add those and then divide by two But it works it works either way Now the other thing what I thought You're asking was it'll say Max velocity X max velocity y well in the the Ross World uh straight ahead is X and left And right is y so that and Z then is up And down and that's why you'll see the Uh See these things listed with you know Velocities X Y and Z or whatever X Y and Z that's that's what they're talking About there got it Sorry to interrupt yeah you're fine Um The other thing I just wanted to touch On briefly is A little bit about how I Moved the programs into one

Um One folder so This is the What's out there In the source is just this folder Ackerman vehicle it's got a urdf nodes Maps launch config as you can see Each of those has in it what you would Likely expect Um Here's a number of the zacro Files there's I just carried over all of them that we Had Um In the nodes at the moment are these Python programs Uh obviously the path follower path Generator that's specifically for doing Something with This Waypoint file as well as this Generated Generated points so as I was mentioning Earlier It's a little bit easier to see here Like the the numbers on line one 11 22 Um I thought I gave it four one eleven Twenty two Maybe I know I gave it four but anyway Um It generated these other You know two through ten and that's What's

Ideally going to be fed into a Some sort of program like path generator But as I mentioned This uh Path generator that we had in our Archives is pointing to move base flex And so In this Version I don't have move I'm not using Move base Flex I'm just using move space So I have to work through that Uh other things maybe to note And this cereal it just makes it easier For me if all of these Yaml files are in one Folder and I don't get A little bit Um easier for me just not get confused Anyway that's um Like I said where I'm And where I'm going work out the Come up with some sort of path follower Routine to You know do something with these Waypoints and then Run that consistently and see how the Speed might change as I look around with The configuration files That's where I'm at So last week Last week I was saying that um I was Talking about uh wiring and I had these Things called ferals and I I don't Remember what else I talked about

There's I was just in general I was Talking about wiring and I said I found These things called ferals and I don't Know if you can see these or not these Are just little uh There's this thing right here is a thing That crimps on So you just it's actually kind of around The fact it is a round pin on the things You slide your wire inside and this Happens to be 18 gauge speaker wire that I found on my box and since speaker Wires isn't marked very well although Here you can see here you can see the White Ah here you can see the white white Stripes on them but I can never find Those white stripes I'm looking that's What I did I took pieces of heat shrink Tubing I found some red and some black And stuck on there and they're not They're not trunk on right now but uh if I were gonna go ahead and use this I'd Shrink those down so I I don't screw That up and then I prep the other end of It I'll put those on too so I can see What I'm doing So the advantage of these ferrules is if You just got stranded wires sticking out Uh once you put these on you don't have Random strands of wire shorten out on Things and if you put them into terminal Strips like say these terminal strips You know it's got the little screw on

The top and you slide something into That you can put wire in there and crank Crank it down but for some reason on Mine all that stranded wire always seems To work its way out so by putting these Things on Let's see if I can get this to fit here That sounds a lot easier than what I've Done which was uh put a drop of solder On it You you can do that but Um this it turns out these these work Fairly well this is the first time I Ever tried using these and uh somebody Else I think it was uh Alan Is either Alan or Ross the guy the guy From from I think he's from uh Um Kansas and he's I think he says he uses These a lot and see basically you slide It in like that and if you can get it to Fit you crank down on that that'll give You a good solid connection and Hopefully they won't pop out So then when you buy them I I just Bought them on Amazon and I got a Package like this so there's a whole Bunch of them in there and see there's Some some really really big ones here And then Works down to small I think it Says 22 gauge to 22 gauge up to 10 gauge and then it Comes with Uh what I bought I bought it with this

Crimper and if if you look at it you can See the uh the whole yeah see the hole Looks like a round hole so you put the Thing in there as you squeezed out of The it's actually a hexagon and it just It just makes it smaller and smaller Until until it smashes it against the Wire so it works just like the other Crimp on terminals it's just that They're they're round instead of the Little Spade connectors or whatever And I I was going to post my my link to Amazon where I bought these and of Course I can't find this exact package There's there's other ones that look Like they're basically the same thing You know from different brands and Whatever and if you look at it see There's a whole bunch of them in there I Don't know how many you know that's Probably about a lifetime supply unless You get get really you really start Start liking these then putting them on Everything but So that was the thing I was talking About last time I said you could use Crimp on ferals and that maybe we'll Take take care of some of the problems The other thing was um This this doesn't really relate to much Except that this is one of the this is a Single channel uh cytron driver board so Terry got one of his dual Channel And then previously people will be using

The big 30 amp one to run their uh their Power steering Motors and that's what I Drive my mini tractor motor on my my Little vehicle that I made and I Terry's Having problems they couldn't get the Thing to run he set it up and it's got Push buttons this one have push buttons On it Should have one No it should have two Uh yeah it should have Anyway I can't I can't see oh yeah there They are there there's the side here so They give you these test push buttons You can push these and it it makes the Motor run One Direction or the other and He he said I should let him tell the Story but I'll tell it anyway he set it Up and he got it to run he can push the Buttons his motor return he hooked up His microcontroller had nothing he Wouldn't do anything so we I I was out Digging and I found some tutorials where They're showing that the the wire the Ground wire between the logic and the Battery that I'm hooked together they Specifically said hook those together And my thought was it's probably Connected on the board so you shouldn't Have to do that but he hooked them Together and it started working and he Disconnected it and it still worked so We were baffled on that if I just like An OHM meter here as the meeting started And checked and sure enough on one side

The the ground pin here for the the Incoming power and the ground pin on the Logic over here are connected together Inside the board so I so whatever Terry's problem was it's still still Baffling so someday we'll we should Track that down to about why but anyway I I have I haven't had an issue with it And I have not connected connected that Ground back together so Yeah and you shouldn't have to connect Those grounds together right because They're connected on the board which Brings up problems later when we talk About noise problems so something I have A feeling probably a uh operator error That might have been and I I don't know So I'll I'll take that one it was an Operator error Still proven otherwise yeah you do have Took up the ground the logic ground from The board to your to your logic just to Make sure you have a ground connection Between right then you shouldn't have Took up the one between the battery and Anything else so well well we'll keep That in mind and then if that comes up Again we can dig into it and figure out Figure out why it was doing that so I the only thing I did on my my robot I Went out I went out and bought some more Screws I got some uh some that have a Like a bevel head they're quarter Quarter 20 bolts and I had big bolts

Sticking out of the top of the thing and I simply went and bought these other Ones and took a countersink and counter Did a countersink you know so it's got a 45 degree hole inside the the board that I was using so that way those are flush With a surface now so I put those on and I was well I was over at Menards I got Some other some other screws to replace Some of them I have so that's that's Really all I've done with that So I think that's um that's all I got to Report for this time so I'll turn it Over to Uh I guess unless there's any questions Any questions on any of that stuff Nope Okay so I'll turn it over to Terry then Okay Um I found a Reddit on Milwaukee Tools So I posted there to see anybody have The battery protocol And um One guy said he had the uh dump of the Hex But I don't think I'm going to try and Debut or De-assemble the uh Text code in the pick processor I found another guy Who responded Quagmire repair.com He has taken apart the board inside the Battery

And is Basically creating the schematic Re-engineering reverse engineering the Schematic And found that it has a Let's see what was it a B A BQ uh Battery control chip and then a a small Pick processor And He identified that the pick processor is Connected to at least J1 Through some other components And so now you he's he's doing the work Of re-engineering the board And eventually I plan on Using my USB SX Um logic analyzer to kind of watch the Flow of data between the battery and my Drill when I run it and also between the Battery and the charger Just to kind of see what the Communications is going over what format It is And see if I can debug it that way But at least we're making some progress Um So a couple of points on that I found Somebody's website says we're going to Reverse engineer that he created a GitHub and about a year ago he he just Archived it and he was done with it so

And that's one that was yeah as you say Somebody was showing hex dumps of Something which uh I I assume it was a Processor and I didn't I didn't notice Anybody saying you know showing you know Actual uh Protocol going back and forth and back To your point about if you can just hook It up and get it running and just watch It with your analyzer that might tell You something fairly quickly because a Lot of stuff on I Square C they'll use The concept where they'll say go to Register three and give me that value so You should be able to watch you know Just a little short you should see Little short messages and it'll say Number three and I'll give you a number Which probably will represent voltage or Current or something and say I might say Number four and give you something else So I was just watching that might tell You enough because I don't see I I don't Think they'd go to the trouble to try to Encrypt that in any way they could and a Real simple way to encrypt things is Just flip some of the bits when you you Know before you transmit you flip some Of the bits of your word and then send It when you get it back you flip them Back and that that'll stop most people Right there so that's something you can Watch and you know get the drill drill Running and run the thing you know just

Just run it slow and then then ramp the Speed up and see if it uh your numbers Uh stay consistent so there's various Things you can try there That's one of those it'd be nice to know I think um Yeah I'd like to do that Um I think I'm gonna for the short term Just put um voltage divider across both Of the uh Across the battery and then using a to d On my uh itsy bitsy to read what the Voltage is okay figure out how to Calibrate it and then have it generate a Message When it gets to like the The 30 down or 30 remaining and then a shut Off message at the 20 percent There might even be some standardized Messages in Ross that should that have Are for battery stuff so it it could be You can find a message is to plug the Values into that and publish that it Might give you like you know your your Instantaneous voltage and then uh I Don't know if their message was set up To do the an alert saying it's down to 20 or whatever but you know you can Create your own messages to do that too So if that's something you want to do You say okay I read the voltage is down To 20 you just publish off a message

Saying uh it is my battery is low and Then you can do whatever you want with That so Hey that's why I was wanting to have uh Kind of the go find the the state the The recharge station as one message it Sends out and the other one is okay You're gonna stop now and Fix human intervention Because it sounds like there's a Some bad things can happen to battery Pack if you uh run it Beyond a certain Point That it won't charge again And it could be the battery smart enough To shut itself down on that I I was Reading very when I was digging for you For your batteries I found a lot of People saying well it's but it's you Know I've had it for for five years but I've only used it twice and now it won't Charge and then various people on YouTube said oh go out and buy this Little battery Uh I can't think about equalizer I think It is so you get this little board Inside you take the battery apart and Solder the wires on and somehow it Equalizes the you know drains the high Ones down and lets the other ones charge Up so that they had some way to to fix Them it did just looked like a real pain Although if they're 100 a piece for the Batteries it'd be worth worth some

Trouble to buy a little five dollar Board to uh to correct for it so So yeah One one thing that one thing that Bothers me that people would pop these Things open and they said it was fully Charged they started poking around and They're saying there's a lot of there's A lot of power there with just these big Tabs sticking out there so so be careful As you do that so you don't short Anything out because you might have Might have a mess real quick by doing That Right And then they had these these just Flying leads coming off the little board And he just grabbed one and soldered Down grab another one solder down and as He did the little LEDs on his his Equalizer board would light up so he Could see what he's doing and but but Yeah just just in general keep that in Mind that you know you're working on Something that's live there because you Have no way to turn that battery off Because you're right on the battery Terminals themselves Right Um So that's Kind of where I'm at with the battery I Want to get my PID at the motor level and then work

Um do PD PID based on um The robot itself but I need to calibrate What the wheel size is so I can Determine Meters per second Based on a rotation You intend to have the quadrature Encoders on your wheels don't you I do Because Well no they're actually on the motor But I'm on this on my Prototype it's uh a direct drive so in Essence it is directly Yeah the only difference there is Whether if it's on the motor as opposed To the wheel that you've got some some Ratio some gear ratio in between there So yeah it's but but my point was what I Find it convenient to convert the meters Per second into counts per second on Your encoders and then you do have to at Least once calculate how many counts the Entire diameter wheel is you know on What what are your encoders going to Tell you but once you get down to the Point where it's in in coder counts per Second for Speed and then distance is Encoder counts over time that works out Well But yes yeah you're right at least once You have to take the diameter wheel and Figure out uh what I do is I like to uh Ideally if you have code that's set up To do position you can say okay this is

Position zero and then run the thing Around to where you think it's Um you know gone exactly one full turn And then look at the thing and say how Many counts was that and then you know Punch that back in and say drive you Know one full turn and see if it stops Where it's supposed to and if you get at That point they say drive 10 turns and Then you can see it does it come out Exactly where you want where it stops so That's just another handy thing to do But that's not really Now to start with that's not really all Important just get you know just get as Close as you think is right and then go With that and then some other day if you Want to get it down if you're off by a Couple of counts then you can fix that Some other day it looks like I've got a Very If I remember right Each turn of the motor shaft If I remember right gives me 96 No 100 and 88. pulses And if I remember right the motor is has A hundred to one gearbox so I'm getting Like 90 to 100 000 on one turn of the Wheel That also yeah yeah sounds like you know Exactly what you're doing there so That's I I I'm I'm remembering back 10 years ago when I was uh working on

The PID at uh At uh at Allen's place I know it was really fun to watch we had Put the uh The PID signal on the scope and you were Able to watch as you put some resistance On the wheel you can see the pi the the Pwm Wavelength increase And it was fun to watch it change based On how much tension you put on the Wheel You just need seeing that that visual Feedback from the Osco [Music] Um And then once another handy thing on That once you if you start using the Arduino IDE you can pull up that what They call the serial plotter so you can Take all your different values and just Plot them out like an oscilloscope so You can watch it so you can see the same Thing you put your hand on you know It'll say here's my current speed going Line like this and then down here is the Motor power and you put your hand on Yeah you'll see the the speed start to Come down you see the power come back up To compensate so that's that's another Handy thing if you're using if that's How you're programming your board you Just fire that thing up well whether Whether you're programming it that way Or not you know that's just a general

Program it'll say take these incoming Values and plot them on the screen so You could you could program your board In something else and then plug it into An Arduino ID and still still get that To work so that's just a quick way to See what's what's going on there to to Debug stuff Does [Music] Um Ross do anything about Um I used to call it the the trapezoid Acceleration curves So that I I think I think it will generate that You know the thing that that Alex is Showing he said something about Acceleration limits I think that's That's what that's what that's doing so You can you can change those numbers That'll when it puts out commands I Think it'll actually ramp those up for You somewhat but I my my thought is you Might want to keep in mind you want to Do that you might want to do that Yourself and if you not don't end up Needing it just set those to say make it A step function and just ignore it Lut Ross tell you how to do it but you know If while you're working on it right now Keep that in mind you might want to set It up so if you type in a step functions

They go from zero speed to whatever 100 Speed is maybe a meter per second that You might want to you know put a ramp Function in there yourself uh to control That But I I remember that I had done that When I was using the 68332. yeah so I'll Have to see if I can dig back and find That uh where I documented that I remember I did Nine scenarios So that if you were Going from Dead start dead stop to dead Stop versus going dead stop to a slower Speed same speed increase speed at the End of that position change I had I think nine different Trapezoid configurations that it would Do I saw a video a few days ago where a guy Was looking for the right Um Microcontroller to Measure the ticks on his CNC machine and He was worried about losing ticks if his Microcontroller was too slow So he discounted Um Most of the Arduino boards And went for A TI board that was running at I think 90 megahertz Um I don't know what that many ticks

Whether you would ever have to worry About losing Losing ticks and the speed of your Um this itsy bitsy is running at 120. And can be overclocked to I believe 180 Megahertz I was wondering what's the Teensy for Running at Do you know where that's running at 600 Megahertz 600. Keep mine we're talking about two Different things here you know what he Says the Arduino is too slow to do it That's because it does not have a Built-in quadrature decode peripheral so You're relying on the processor to do it So you go out and you get the arm chips That have the peripheral built in They'll they'll take something like a Two megahertz Um input uh the counts from your encoder Can be up like two megahertz or Something and you're totally avoiding All this nonsense they do on the Arduinos where they create their own Quadrature decode functions to do that So you really got two different things Here there that you're talking about But but but yes to start with uh if he Just takes his board his board is faster Than a regular Arduino so he's got a Much better chance of that being able to Keep up Um if if you have to do that now I as as

I said all along I prefer to buy a Processor chip that's got that built in And I had the uh the ti This one this one's got a little TI eval Board in here and it's got a like an arm Cortex four and it'll do two channels And quadrature decode so you just hook It up and those just work and then all The St micro parts Seem to be able to do I I'm gonna say all of them and that Might come back to bite me if I say all Of them but even that little blue pill Which is like the older like it's like a Cortex M1 or something and that that one Will do it too So the quickest thing is hook it up to What you got dropping the the Arduino Quadrature decode and see if it works And if if it works go ahead and use it Until you decide to do something Different if it doesn't work then you Can look at something you know doing a Different taking a different approach to That Sounds good And then the other thing I keep thinking About is those little blue pill boards You can get them for like two to five Dollars a piece and it's uh it's like a Like a 90 45 to 90 megahertz uh arm Processor and it's got the extra Peripherals built into it yeah because You can always use one of those as a

Peripheral processor and then talk to Whatever whatever processor you got on The board so hook it together with i Squared C or uarts or whatever and just You know program the the little board to Do just the stuff like in that case you Get the quadrature decode for free if You if you drop that board on there so You know more things like that you can Think about try it on your itsy bitsy Board first use the Arduino libraries if That doesn't work then we can come up With some other way to uh to get around That I'm using a encoder Library that's Specific for that chip It's not specific for the board but for The um S-a-m-d51 [Music] Well be careful because the 51 and the The 21 may be different it could be it Has the peripheral in the 51 and not in The 21 right but it's built specifically For the 51. Okay but you don't have a 50 worth Uh no the Itsy has the 51. well I Thought that had a 21 on it Anyway that's things to think about just Keep that back Okay Um my plans are to uh do to complete the Uh PID on the uh Rounds per minute which will then be

I'll be able to calibrate to uh Meters per second For the PID on an individual motor and Then work on getting it for going Straight with the robot at a pie And then um Figure out how to work in the turns Sounds like fun Hardware work And hopefully along the way wire up my Uh Batteries actually onto the robot Um So they're fused and switched and so Forth instead of having to unplug the Battery when I want to stop playing with It So how many cells are in that battery I believe five to give 18 volts Um Maybe it's maybe it's six no I think It's I think it's five for this one the Reason I ask is because after the last Call I looked at some of that Milwaukee Stuff and I don't know exactly what you're trying To Um Reverse engineer but I assumed those Middle wires were not Digital Signal wires their voltage wires For the battery management system The battery management I believe is Actually on in the battery itself And the the five

The outer two are the battery output Plus and ground The middle one is battery voltage input And then the I'm going to call it two And four Are the uh communication lines So I mean you're Like a digital signal not So it's the B okay I mean that would be Fascinating that they put the BMS Um Inside of what you just held up well That's where they're using that um The BQ chip and the pick processor and That's in that that's actually yeah It's in this M18 Interesting This uh The uh Quagmire repair He uh sent me a an email back Um Showing the the boards that he took off Of the when he took the thing the Pack apart And uh He he's Re or Documenting I guess what he what can all Of the connections that he's finding in All of the parts that he's found in There interesting But he he started it January 1st so he's

Still very New into it And we've just done a lot of back Engineering Just as a I mean an interesting point that The Um The battery that I have on my tractor Has its own well I mean it was all it's A DIY job like a Frankenstein thing but Uh The BMS has a Bluetooth Connection and I'm able to get it here Because this room happens to be Over the garage and um The battery has gone from like 14.3 volts to 14.2 volts and Like uh three weeks Without being charged without being used Or charged Um So I thought that was pretty interesting But it has four I don't know if you can see there's four Cells there and each one of them have You know separate voltage Yeah I I I don't know how much Information is available and that's why It would be great to get the the Protocol from From Milwaukee but I I don't think They're gonna Give that out

Yeah I mean if that's a digital signal Then you could write your own code to Sit there with your own exact Bluetooth Thing with your phone and see what's Going on with your little battery That would be sweet Yeah and if I can figure out how to do The reads then just kind of sequence Through till I get nothing back If they're register locations memory Locations Cool Yeah do you have that plastic adapter Handy right there If it goes on your battery Is it going to be convenient could you Put a couple extra tabs in there and Hook your your wires onto for your Signal It would not be convenient You have to pretty much take it apart What I would probably do then Is Um Got a friend that has a 3D printer and See if he could 3D printed for me With the extra tabs Because that's just something you'd have To think about editing along here to Figure that out but foreign Solder some wires on some tabs and shove Them your battery and they just hot glue Them or something then so the the wires

Go with your batteries you're moving on And off as long as you're not going to Try to put it back on your drill that Would that would be a way to do it right But no I I my my expectation would be That Once I uh If I get the protocol figured out at Least you get the the battery capacity And voltage levels from the battery pack Itself That I would have to Get or make new A new um Jack I guess can be the best term for it That has all five In place Another adapter is there any kind of a Latch on that or you just simply put the Battery in your gravity is going to hold It down to keep it in well the the Battery itself See her again has This Squeeze And it connects it's a hard connection Into it's a latch into that adapter okay So that when I do this There's a hard snack and it won't come Out Until I do this okay And the other thing keep in mind you can Use that as your switch too so when You're all done just pop the battery off

And lay it on the table and then you Don't have to have you know right a big Power switch in the way that's just one More thing to screw around with so that Would be handy too if it's convenient to Get the battery on and off Well I already have that um Switch wired up from my old system when I was using the RC batteries Where I had one set of batteries giving Me 21 point Six volts And the other one giving me the 7.2 I did oh that's another thing I did get Um I got this uh Switching power converter that takes uh Seven between seven and 36 volts down to Um Five volts 3 amps So that And that particular form factor they've Got it up to I think 20 amps But I only got the uh I've got a pair of The three amps Tons of rabbit holes to go down yep Which is why I think the uh just doing The the voltage divider and monitoring The voltage Is probably what I'm going to end up Doing for the short term Unless I find someone who's been real Ambitious with this and decoded The protocol

Fancy term is minimal viable product Foreign If you can figure out a way to connect Your your logic analyzer to your battery While it's on the drill you can go ahead And take some some dumps and just see What it see what it looks like If it's real I squared C I think the USB Analyzer says apply this decoder to it You say it's I squared C stuff and it'll Show you You know it it'll help you out somewhat There so you're not just looking at Lines wiggling at that point right And more than likely especially if They're going to connect to a pick Processor they probably just use the I Squared C peripheral in that so I'm Guessing it's it's going to be real I Squared C so then it's just a matter of You know say oh I found a start bit or What do they call it an i squared C and Then you know the the standard protocol Is something like you know given a Number that's usually you can either Think of a register number or a command Number and then there will be you know One to one to several bytes of data Depending on what they're trying to send You if it's a voltage you know it might Send you a 16-bit number or a 32-bit Number whatever but if you can see those And then while the thing just runs you Know just check those numbers over time

To see if they're changing especially if You have two different batteries laying There one that's charging one that's not You know go back and forth between those And see what the numbers look like Between those so that might give you Yeah if nothing else you could probably Probably get the battery voltage out Immediately by doing that and then if The if it's capacity left you know again Swapping batteries you might just people See that change between the two So that might be you know fairly fairly Simple thing to do And I'm guessing those are going to be Five volt signals on that uh On that I squared C it's uh you might You might want to check that first you Know we just put a meter on and see does Do those pins say five volts or they say Something other than that And that right I think a USB probably Works on either 3.3 or 5 is my guess I I Don't remember it's been so long since I've used one of those Well the uh the USB is very that's very Forgiving Um well forgive 18 volts that your Battery is 18 volts they might I I would Be very surprised if it's doing its Communications at Given that it's with the pick processor That it would be above the five poles Something in between there yeah I think

It'd be foolish for them to put 18 volts On that signal but you know again if you Just measure take a meter and measure it And see what's on there before you start Hooking stuff up to it Yep Foreign In fact it could be if you just you know With a battery layering on a table Because the thing is powered up right Now it's all the electronics are running Right now and that that battery so just You know look at it with your thing and It could be that it's it's just randomly Uh talking out there saying oh hey Here's my voltage oh here's my voltage But it could be you'd have to prompt it You have to go out from the outside World and say tell me tell me what this Value is so that that's my guess is that It's the uh Non-battery end is going to be query is Considered the master Whether it's the drill or the charger And that that's going to request the Information from the battery that Probably makes sense yes Um I guess the other thing I've done is I have gotten uh I still have Ubuntu 20 loaded onto a lap an old laptop I Have not done any more with loading Ross On it Foreign don't want to split my focus too

Much Um I have ordered some 3.3 volt zener Diodes so that I when I do my voltage Divider I can make sure that I'm not uh Putting anything over the 3.3 volts into The ADC Those aren't scheduled to get here till Somewhere between the 19th and the 26th Foreign Software Configuring pids there's only two or Three more things you got to do Terry And then you'll be you'll be serious Okay I've got a phone call coming in so That I need to answer so I'm gonna Go silent for a moment okay Anything else Jeff Um You know when we're all done I was gonna Ask Terry when he started the Twin City Robotics meetings but I will wait to see If he comes back on that or if we run Out of things to do I guess we can just Move on I I was thinking you know the last time I was saying I should check out my my Giant RC Servos to see how well they're Tracking And you said hey you should make up a Video on that well I haven't made up a Video yet but I think if I just take say Here's one of my RC Servos And if I this one doesn't have the wire

Soldered on the pot yet but if I'd go Ahead and solder that wire on if I just Connect this to an uh say an Arduino Nano so the Arduino Nano can generate The pwm to tell it to move and then Measure the analog coming back You know I should be able to do some Something that says I can plug in a Servo and then write some kind of Software that says you know go through Some pattern and track it to see you Know is it following like it's supposed To and then I could try it on on this One this is the this is the just the Chinese one random Chinese one I think I Bought on Amazon or Ebay and the ones on My mini tractor I thought was working Well is the one from mpja I know those Are all out of stocks I don't know if They're not going to sell them anymore I Don't know if they can't get them or or Whatever the deal is on that and then I Can plug in my uh my um here's the Here's the super Servo 200 and it's this Blue wire is the feedback wire that I Put on the thing so you know technically I can try it any of those and I assume If I go into just a standard Servo like This that's what I quarter scale uh Probably if I go to the pot inside of That solder wire I can do exactly the Same thing on this so I could I could Check it against you know real Real servos as opposed to you know uh

Well as opposed to this one that Somebody's hacked up so that would be an Interesting interesting thing to do And I think it would be relatively Universal that I could try it on you Know a micro server with a standard Servo and a quarter scale and and so Forth just to see see how well those Things track so that that would be a Worthwhile thing to do if I if I get Bored And the only the only difference is the The big servos put five volts out you Know you put them on 12 or 24 volts into Them and they put five volts out and the Other one's like you know like a Standard server like this you have to Actually Supply Power uh like 4.8 to 6 Volts power into the connector so that That's the difference between those two But I thought I thought I could see Through the server when I was doing this But I might just been reflecting blue Light from somewhere so I I guess I was Confused there for a second Well that'd be handy to go through you Know whatever I can find laying around You know try try various ones and run Them through the same program and plot Out the the response on them just to see What they do So that that you're right it wouldn't be Good to make a video on that put it up So other people can look at that and see

It That's that's all I got to say about That at the moment I guess if I if I get Back to that I'll have more to say on it But Good deal I think I'm all set Gents I'm all set okay well I'll stop it then