As some of you know ive been trying to complete a 3DOF Hexapod spider using a Torobot servo controller. Well i burned it out about a week ago and ive been trying to do some research on a more plausible choice of controllers so i can get the movement i want and all the extras.
I read up on the Pololu 32ch maestro. It seems they do have a sequencer but i can further develop thier script too. I also found some good information on using the PS2 handle with the arduino and there seems to be some libraries already compiled so that will make things easier. What i cant find is where to plug the wires from the reciever to the arduino nano. Just what wires do what. But i plan on trying to use the Maestro to control the servos and the arduino nano to give the signals from the PS2 RX to trigger the movements i want.
Im also thinking about buying one of these Decepticon controllers with the white board. I think the original producer was a conpany called arcbotics or a company called Lobot. They all look the same but with different brandings. They also use the same sequencer. Any way im interested after reading the manual for the software. Its all about the offline control. You get more button options that allow for different modes like tripod or ripple. And it seens thier controller firmware allows continuous motion while the button is depressed and stops when the button is released. Thats a big deal ti me after the horrors of the Torobot controller which is start and stop.
Any information you guys could give on the arduino part i would really appreciate it. For instance what wires go where on the board for the PS2 reciever.
Heres the link to the
Heres the link to the Decepticon controller im talking about…
http://www.thanksbuyer.com/download/25363-32%20Channel%20Servo%20Motor%20Control%20Board.doc
I need whole electronics system to be as compact as possible so i can attach it to the top, thats my main reason im going for the maestro-nano configuration or all in 1.
The guy that made the info page for using the PS2 RX and handle also wrote a PS2 controller arduino library and it has examples on using almost any PS2 controller like the guitar.
Heres the link to the info.......
http://www.billporter.info/2010/06/05/playstation-2-controller-arduino-library-v1-0/
I found the diagram for hooking the PS2 to the nano but cant find the way to then connect the arduino to the maestro.
I think im gonna like this
I think im gonna like this Pololu controller. You should read the info page here…
https://www.pololu.com/docs/0J40/all#1.a
Seems to be way more than any of the all-in-ones ive been buying. The software that comes with it allows you to do everything from perfecting your sequence to compiling to thier "script". Also it has loop commands and if statements which is a major attraction to me and ease of use. And you dont have to use the sequencer more complex movements can coded using thier "script" too.
The only draw back that could be changed is having to use a seperate micro controller to make your bot wirelessly controlled. But even that looks pretty simple to pull off. From what ive read i just need to hook up the TX,RC lines between the two. So all o have to do is program the Nano to use the PS2 controller then have it activate my commands.
On this
On this page…
http://store.curiousinventor.com/guides/PS2
.......it says that i need to solder a pull up resistor to two wires 1 and 9. Am I to assume that these go in-line with the wire? Like wire-resistor-wire?
I still do not understand
I still do not understand what im supposed to do with the resistors. Maybe you could send a pic?
On the othet hand i found another page where a guy hooked up his wireless Rx to the Nano and mentions nothing about a pullup resistor
Played with the pololu a lil bit today after making some wiring changes and got it walk using my Ripple gait. Also the loop function has no delay which is awesome but i could use a lil advice on continuing it right. Right now it stops with the last leg up and when it loops it stresses cause it goes back to the first frame. So i need to continue it some how where the last frame sets it up to start the first frame when it loops.
Im gonna start trying to code the arduino to send signals to the pololu in the next couple days and hope i get the pololu to understand and interpret it.
Cool thanks!!!
Cool thanks!!!
Could some one please
Could some one please explain how to do a ripple gait turn. Just like the first couple legs after that i should be aboe to catch on. Im Watching vids but cant pen out movements.
Ok I took two resistors and
Ok I took two resistors and two servo leads and soldered a resistor to each one then i used liquid electrical tape to seal them. I soldered them to the tops of the leads that hook to the pin of cmd and ack then ran them to a 5v power source. Before i add power can some one tell me if i did this right?
The resistors are labled 10k
The resistors are labled 10k ohm 1% 1/4w.
What your seeing are wires coming off the PS2 wireless RX plugging into the the arduino nano. The green wire is connected to D11 and the blue wire is connected to D12 and i have a resistor wire (red) running from the top of the blue wires plug to the VCC.
Still kinda new with the solder thing.
I dont have any thing to test the resistance with. I was just trying to follow the directions on Curious inventors page saying it needed a 10K ohm resistor on those two wires. And im afraid to add power til i know if i did it right.
Heres the link to the page.
http://store.curiousinventor.com/guides/PS2
I just gapped the rubber on
I just gapped the rubber on the two wires about a half inch from where they go into thier input pins and soldered the resistor wires there.
After changing the resistor
After changing the resistor wires positions on the data and command input wires i decide to go ahead and try to code the nano to accept the PS2 comnands. It was pretty easy i understand a lil of what i did but it did compile and load on the board after fixing a couple syntax errors.
Now i have to figure how to add the part so the nano will send and recieve serial communication from the pololu. The script example is small like two paragraphs. Says im supposed to change a couple settings on the software then paste list of functions to my script, then i have to add something to my PS2 code so it will understand each other or however it goes.
Im running my system power through a 5v UBEC then connecting that of course to the pololu VCC. To power the Nano i ran an auxillary line from the pololu to the nano then the wireless PS2 unit to the Nano all in a chain. When i plugged in the nano to the usb it powered all three devices. Wasnt expecting that.
Kinda new to soldering and stuff. I used to use shrink tube but the area around was thick and hard to manipulate. I like my liquid electrical tape. I seal smaller places. I was perfect for my palm sized quadcopter i built. The wires for the motors were so tiny and fragile and kept braking on my me with lil manipulation. So i slathered the goo on and it toughened em up.
Ok ive been trying to think
Ok ive been trying to think of a way to do a ripple gait right turn. Im definitely gonna need some help with this one. Cant decide if i should do it with a transition of 5* to 10* like i did with my ripple gait. Heres a sample please let me know what you think.
#1
Lift leg 1 rotate forward to F30*
#2
Drop leg 1
#3
Lift leg 5 rotate reverse to R30*, rotate leg 1 to F20* leg 2 R5* leg 3 to R5* leg 4 to R5* leg 6 to R5*
#4
Drop leg 5
#5
Leg 3 lifts and rotates forward to F30* leg 1 reverse to F10 leg 2 to R10 leg 4 to R10 leg 5 forward to R20 leg 6 to R10
The R and F mean Reverse and Forward and are the coordinates to put each leg.
Well i got it right. Got it
Well i got it right. Got it left too, all in one spot.
Well i'm still trying to figure out how to get the pololu to accept commands from the arduino so i hooked up the decepticon servo controller. Its got some nice features like auto loop and the wireless control supports turbo buttons. One thing i dint like is im going to have to use two batteries. The board power needs at least 7v in order to operate. The servo power though still is at 5v. At this moment i soldered a wire from below my 5v UBEC but both drawing off the sane battery just kills the juice after a few loops of movement. One of the other features i like is that you can easily change modes so you can use all three gaits ( ripple, tripod, wave). It also seems to support in its firmware to be able to automatically choose a leg for one leg at a time feature.
Ok all my servo controllers
Ok all my servo controllers are doing the same thing. The board power never fades but when i add servo power i get a few steps movement or a couple minutes not moving amd then it all goes dead. I was looking and found a post that said MG90s servos draw .21Amps. .21 X 18 = 3.78amps. My 5v UBEC only puts out 3amps. Should i use something like a 6amp rectifier bridge to raise the amps?
Out of the three Boards i like the pololu the best. Only problem is i have to do some programming to get the PS2 handle to work. Theres is a PS2arduino library found here that compiles so the PS2 handle works through a Arduino Nano found here...........
https://github.com/madsci1016/Arduino-PS2X?files=1
I copied the example and i think it works but i dont how to tell. Though when i press a button a light lights up on the nano.
There is also the Maestro\arduino library found here..........
https://github.com/pololu/maestro-arduino/tree/master/examples/Script
The example supposedly says it how to activate a subroutine(sequence) but it looks more like it shows how to control a couple servos using the Arduino to supercede the pololu.
What i think i need to know is what bytes the arduino transmits out when a button is pressed and held. Then i should be able to get the pololu to activate the command connected to the button.
I was looking at the PSX_lib.h file and it lists buttons with numbers it calls constants that look like this 0x0100. Could these be the byte packets i need to know?
Hmmmmm i already have one of
Hmmmmm i already have one of those but its way too big and leaves no room for a battery or a controller.
I ran across this one............
http://pages.ebay.com/link/?nav=item.view&alt=web&id=291333901758
Its only pushing 5A though. Would that work?
Ok i was looking at the
Ok i was looking at the pololu home page found this regulator under power heading…
https://www.pololu.com/category/131/step-down-voltage-regulators
They have them all the way up to 9A. Would the 6A be viable or should i get more amps?
hexapod power
My hexapod has a 3A switching regulator for each leg. Havn’t tested yet but prior 6A (2 3A units) total went up in smoke.
Dont know how i could supply
Dont know how i could supply that much to each leg. Maybe if i chained together a bunch pololu’s.
Found this thread. Looks
Found this thread. Looks like the MG90s servos draw around .21A per servo so times that by 18 and you get 3.78A total pull.
http://www.rcgroups.com/forums/showthread.php?t=2118842
If the thread is correct a 9A regulator should be plenty.
I just found out you can seperate each servo bank on the pololu but i could only find a short blurry video as info to what a "cuttable trace" is or how to do it and its a horribly shot video so you cant see whats being done.
Been looking at ripple gaits
Been looking at ripple gaits again today. Noticed that the front and rear legs never move past thier respective mid-positions and pull or push depending on the direction of the walk. That will change my degrees of motion from start to trot on those legs. Instead of starting at 5* and working up to 10* per frame ill have to start those legs at 2.5 (or the closest estimated integer). Then switch those legs to moving 5* at trot. The middle legs wont change. Sooooo…
1st leg lifts rotates to F30 while stretching out the leg to its full out stretched position.
1st leg drops starts pulling toward body
5th leg lifts rotates to F30 1st leg pulls in and rotates reverse to 27.5*
It will be more involved. But the example should be correct. Back legs will be fun to do!!!
