DIY Electronic Controlled Motorized Wheelchair
14 presents im wesley gardner, aka gametech, and today we will be taking this wheelchair and motorizing it Music. When it comes to mobility, not everyone can afford a powered wheelchair or something similar to get them around. Even if its slowly to inch them forward to move them forward to a table or to inch them away from the sun, sometimes these little things we take for granted. I came up with this idea as a diy project, so anyone can do it at a reasonable price to help anyone in a wheelchair with their mobility needs, so this unit will be meant for flat ground so like in a facility or in a house where its Completely flat theyre not going to be going up and down hills, this chair is meant to go slow. All the parts for this project will be listed on the element14.com website, where you can download all the files all the code, everything to build your own, so lets head over to the computer, check out the design and get printing Music. So when i first started, i decided that i would build a little demo station, where i could you know, test things out and go from there. So this one here right up front is my original one that i designed so i could get my whole spacing and everything kind of in line, and i knew what i was doing and, as you can see, i made a bunch of different connectors because the tubing On the wheelchair and uh, the conduit were two different sizes, so we had kind of had to adjust and make some more there.
So originally, i wanted a friction mounted wheel for the motor to run on. I originally started with these little itty bitty rollers. Here i thought you know i was being cool and designing it well, but if you look over to the right here on this big guy over here, this is the guy i ended up going with so i know the joystick controller here, isnt the best design. I will probably adjust this and change this later on, but for right now it should get us up and moving itd be kind of nice. If we just you know, snapped our fingers and all the parts were printed on the bench behind us. We have our parts here on the table. As you can see, there is quite a bit going on here now. Not all of this stuff is going to be used, as you can see at the back there. There is my failed designs, so there is a bunch of junk here that isnt really needed. We have our crossbars for underneath the wheelchair, and this here is that mount that were going to be able to mount our two arduino boards with the l298 n boards on it were gon na make our charge port our on off switch and our joystick and our Arduinos and thats it thats all. We need to get this going. This is the original demo station that i had built ill, probably play with it more in the future.
Basically, when i first started this project, i was just going to use one arduino uno. This to me just made more sense that way there was less commands going to one and causing glitches in the code. There was some issues, so i decided to go with the dual arduino board. Three quarter inch emt conduit here slap our battery tray here so theres. The battery that were using this is a genesis, uh np712, so thats a 12 volt 7 amp hour battery, and then i will put one screw in rotate it because you know what sometimes you just dont realize that theres uh, that limited amount of space in here And since we dont have quick releases on the uh tires of the wheelchair were unable to get a drill in on the left side here enough to lock it into place so im just going to sit. This here were going to go here, okay and then were just going to rotate that upwards, get that somewhat straight. Here has a little wiggle room, so we can get that aligned into the proper spot. Here were just going to go right to the back here and then were going to do the same thing with the other side. Here, like i said, ive pre installed everything and that way we can quickly get this done the one day you need three hounds just to hold it in place until we get our crossbar on, got that just about right.
There thats good nice and sturdy now and then were just going to go ahead and grab our our wheels here, so it doesnt matter which side we place it on what weve done so far is we have put everything and mounted it here. The only thing left to mount is the joystick box here. So if i go like this, as you can see, the wheel roller is actually friction mounted to there and the other side is going to be the exact same up here. So we now have good tension here once again, a cheap project that anyone can print and build themselves. So with that being said, im gon na start running some cables here, so that should be one cable down uh. We should be able to just uh. Do the other one, the other one i do believe has a different wiring, though, for some reason all right so were just gon na tin. These guys here, okay, there we go. That looks pretty good just like that shorten those cables up and they will tuck under there. Okay, so weve got those two taken. Care of next is going to be wiring doing the controller cables. This is going to be our joystick here. Basically, what were going to do is we are going to connect all the grounds together on the bottom here and then we will just have one ground wire coming off along with the four directions. So on these guys here there is a little ridge here.
So if you look on your uh unit here uh, you will see those ridges and that is where youre gon na snap it into place, and hopefully it shouldnt fall out with that being said, what were going to be using for our cable on our joystick is A cat 5 ethernet cable that i just had laying around, but the reason why were using this is one its already pre sleeved and it has enough wires for our controllers. So we can get that run to the arduino board, just going to cut and remove some of the sleeve here we dont need any more of that. I think i will take probably about five or six inches. I think that is about five inches there and uh im going to use that, because we can always trim later on the brown white is going to be our ground. Just use one of the directions as the way that we want to go for our down arrow and thats, where our main cable here is going to kind of go. So that way we can actually have that at the base of the unit. So i do have a multimeter here so im just going to put it on to continuity here and were just going to listen for the beep here. Okay were good, and if we go here perfect, we have a controller set up, so were gon na put our screws in the hole like so now.
That should be all right. Sticking up, i dont mind that i know some of you guys, like the blue stuff, but im partial to the green stuff. Not all of us want the blue stuff forgot about the boot on the controller there. So then we want this guy here and we flip it over here and then we just go ahead and put it on in and hopefully all the screws stay in place. While we mount it in here because then we can get the nuts threaded on the bottom. Here, like that, there we go just got to get it on there just a little bit, and then we can go. Take the tape off and thread it on tighter and now we have those screws all in im, just going to go ahead and tighten them up. Dont need to be hercules on these ones. Now that we have our joystick wired up, we can now get it mounted onto the wheelchair. Are you an engineer? Electronics, hobbyist or maker join the element14 community, where you can learn about new products and technologies, see cool projects and connect directly with the people that make the products and engineers that use them join now and there we go. We have our controller set up on the wheelchair there, as you can see now. The cable is coming through here and then its coming down in behind the xlr and power and down to the final turn. Here we have it all wired up here.
Weve got the l 298 ends set up. The only thing we need to do is get the code uploaded to the arduino unos uh power is running right now. Well, its not running, you have to hit the power button on there. You go motors engage and we have a working setup now the whole wiring. It looks like a lot right here. Trust me its really not okay, so i have the software set up here and im just going to go ahead and plug in the left motor here. Its going to be this guy right here, so just a quick look here at the code here i am just setting up the pins here. Basically, the most important thing i found is: we want to set the stepper idle to be low and what we want to do that for is so. Our l, 298 ends, dont start overheating on us right and then were gon na set our left and right. Our revolutions per minute, all that kind of stuff here, since it is just a little creeper, uh wheelchair we were not going fast. So i have all the pins set up here – theres, not really too much to this, its very basic uh. Once you play with a couple of motors, you will get the hang of this really quickly so make sure to check out using motors with arduino, because it is a lot of fun and you can branch off fairly quickly to projects like this.
Okay, so looks like that is complete, so now we need to do the right motor there we go so now. Weve got our code installed on both of these guys. Now we can actually what im going to do is get something to raise up the wheels here and im going to power it on and just see if my codes working or not, if not ill, have to adjust my code a little bit all right. So one thing i forgot to mention is that i did have to swap the cables from one of the motors over to the other side because well you know the motors are actually rotated right. So just keep that in mind, it will be on the wiring diagram. So just keep that in mind if your wheels are going the opposite way when they should be going the same way. There is ways we can do this in software, but this is the easiest way is just to swap your cables. So now all were going to do is were going to test out the joystick here and make sure our wheels are spinning in the right direction. Now i do have the forwards and reverse uh, inverted and thats, just because i wanted to play with it that way. So all im going to do is im going to power it on and lets go. So we got that guy and go reverse Music. So when we go right, whats going to happen is one wheel is going to go one way the other is going to go.
The other way, and that way its going to give a quicker moving pattern there. The thing is, is we can always slow down the stepper motors in the code uh right now. I think i have it set to 150 revolutions per minute. Im hoping its going to be enough tension on the wheels and enough torque to actually move me if not well see how much weight it can hold. This is a great starting point and at a really low cost i will be redoing the joystick at some point to fit on armrests a little bit better. This does the trick, but its not exactly what i wanted. We need to be able to charge those guys. What we have here is a 12 volt uh automatic float charger. This will do 12, volts uh 500 milliamps on the charging cycle, so this charger is probably the most cost efficient way to be charging our projects like this. Just because the price point – and we can adjust it to whatever connection we want, we dont need the you know alligator clips on there and it has a nice indicator for if its fully charged itll automatically shut off, we dont need to do any extra work. So im going to get this taken apart here, so we can get this soldered up all right, so weve got our xlr three pole here all were gon na. Do is just clip these off im gon na leave, basically just a little bit here, because we might wan na reuse these guys in the future, so ill leave a little bit of wire there.
So im just gon na cut it right where it kind of goes into one and well do it up there, so they nice nicely stay together there here, Music, bang and something like that anyways that will be more than sufficient and, like i said, pin one we Want to make sure is our ground. Pin two is going to be our power, so now we need to get our sleeve on here first. This is what we want to make sure that were able to screw into the bottom housing here. So this will slide together. Like this and make a beautiful little connector here so all were going to do now is were going to slide that through here and there we go. That looks pretty darn nice, but i dont say so myself and im just going to slide that down the cord. There all right there we go, we now have a charger. Well, almost we got to put this all together. Now weve got a beautiful new xlr charging cable. We are in the off position. I have the charger plugged in and either one of two things are gon na happen. Here were either going to see a charge, light indicator on here or that were charging. So green means charging when its done its off, and then we just have power. So lets go ahead and lets test this out. There we go weve got this guy charging nothings powered on everythings working like it should, because we have all the power going to the switch so because its in the off state, nothing is being back fed into the arduino at all its cut off from the battery Music, so there is definitely a few things.
I would love to change on this, build knowing more now that ive progressed to this stage, so definitely redesigning the rollers changing the motors to maybe something a little bit more powerful, but keeping within that 12 volt range because were set up here with the motor controller. All set up ready to roll, it would be a quick, easy swap and we would just have to print some new mounts not too hard uh other than that this chair uh with the power. I im curious to see how long we will be able to run it, but we have a charging. Now i love these xlr connectors. This was a really fun build. I had a lot of fun with that.