You are never to old to learn and try new things. I think one of the best days in my life was the day I discovered the Instructables web site. It opened up a whole new world to me. This is my third instructable . I really enjoy building anything that I can ride on or get in to.
I bought an Arduino Uno and was planning on building a balancing Robot. I was really impressed with the Balancing Skate Board that was published by Xenon John. It had most of the code that I would need to build a balancing something. That something evolved from a Robot to a Sit Down Segway clone, which I named the SITWAY. I want to at this time thank John for all the help and patience he showed me in building and testing this ible.

This is my second project involving a discarded electric wheel chair. The motors have great torque and are very reliable. They use 24 volts and have great range using two U1 type garden tractor batteries. You can't go any cheaper than that. 

The build went pretty smoothly. Thankfully Xenon John pitched in and helped me modify his code to work with my wheel chair motors.
After running all the tests I felt were needed I elected to have a young neighbor take the first ride. It turned out to be a real blast. So far eight or ten people have ridden it, the youngest being 12, and the oldest 81 (me). The training wheels limit the speed by limiting the forward tilt. I plan to keep the rear training wheels on permanently because I don't need a lot o speed going backwards.

The SITWAY appears to be pretty safe, but it does not have all the built in backup systems that a real Segway has, I have only tested it on my smooth driveway at this time. I have driven over small objects, and it still stayed stable..Any one can learn to drive it in about 5 or10 minutes. With all the testing and driving we have done I have yet had to charge the batteries. The original wheel chair had a published range of 20 miles.. HAVE FUN!!!


           Item                                                                        Source                                                                                         Cost

1. Donor electric wheelchair                                  Various places                                                   $50 to $200 Depending on condition
2. Arduino Uno                                                      Maker Store                                                       $30
3. Arduino Uno Proto-shield                                  Spark Fun                                                         $15
4. 5 degrees of freedom  IMU                                Spark Fun                                                         $49
5. Sabertooth 2X25                                               Dimension Engineering                                     $129
6. Two surface mount LED's                                  Radio Shack                                                     $1.29
7. Two Momentary contact switch's  (trim)             Radio Shack                                                      $1.29
     (normally open)
8. Two micro switches for Steering                        Radio Shack                                                      $3
     (normally open)
  9. Single pole single throw  power switch             Radio Shack                                                      $1
10 13X20X1/4" plate for base                                Local                                                                 $10
11. 1/2" steel tubing for seat frame                        Local                                                                 $10
12. Vinyl and foam for seat                                    Local                                                                 $4
13. Asst hook up wire                                             Local                                                                 $3
14. One can spray paint                                         Local                                                                 $3
Total                                                                                                                                                 $309 to $459

(note) I actually bought my used wheelchair for $35 at a yard sale
It was pretty beat up but the motors were good and even included
A 24 volt charger.My project cost less than $300.
<p>Awesome work!!</p>
<p>What a Ride???</p>
<p>the name is as good as the product</p>
<p>as you say: we are never too old to get amazed! Congratulations! Great project! Instructables also opened a new and extraordinary world to me!</p>
<p>Really crazy..!</p>
<p>Sounds good. Let me try for my friends mini project.</p>
<p>Good option for old people. Nice one.</p>
<p>I wish my grandpa was a maker too!!</p>
<p>that's clever, how does it stay up though?</p>
<p>If anyone is experiencing problems communicating with the Sabertooth could be the use of the SaberSerial.print instruction. You can try with SaberSerial.write instead. It happened to us...</p><p>Great Instructable!</p>
<p>Wonderful project, and what a wonderful workshop you have!</p>
great Instructable! ! I was happy to see you guys wearing a helmet. keep up the good work, can't wait to see your next project.
<p>Mickydee</p><p>Great Instructable! I have made a similar segway type unit using wheelchair motors. I cannot get it to balance by its self. Can you tell me what PID parameters you used to get yours to balance?</p><p>Thanks Charlie</p>
Awesome work sir!! I am really happy to see you putting your experience for such innovative work &amp; sharing it with people. <br>I am trying to build a self balancing scooter for my son, But here in India I am not able to find Sabertooth 2X25. So trying to figure out a way using high power transistors (2N3055) to drive motor. Will share the details once I am through with it. <br>I wanted to know how is the motor connected to the wheels. If possible please share the images of motor connected to wheels &amp; also the specifications of the motor. <br>Once again thanks for sharing.
<p>The motor and wheel are all in one unit from a powered wheelchair. There is also a gearbox included in this mechanism which means the motors spin quickly but the wheels turn slowly (but with a lot of turning force). If you can find a powered wheelchair to look at you will see what I mean.</p>
Thank you very much sir!
<p>Hi all,</p><p>The analog output IMU's are proving to be very hard to find now. I have finally managed to get a self-balancer working with a DIGITAL IMU that is easily available from Sparkfun. I have used snippets of code from all over the web to get it to work. I posted an Instructable on it here, with Arduino code, in case it helps anyone who is unable to obtain one of the older IMU's. Have tested it on my self-balance skateboard and it works fine.</p><p><a href="http://www.instructables.com/id/Arduino-Self-Balance-Controller-using-DIGITAL-IMU-/" rel="nofollow">http://www.instructables.com/id/Arduino-Self-Balan...</a></p><p>John</p>
hi we Ecuador mechatronics students interested in your project we design and the programming code as we need for a project grade so beneficent a donation
I built a stand up segway based off this code and everything works except that when it goes forward, it will eventually slow down and not keep a constant speed although I'm still leaning forward. any ideas on what values I can modify to fix this?
Mickydee I'd like to thank you and Xenon John both for two great instructables. As an Electrical Engineering student the Sitway seemed like an awesome project. I still have to build my frame, but i have all my electronics wired up on a test board to work out the code before building the frame. For those who are looking for a replacement for the sparkfun 5 dof IMU I have found one, the balance point isn't quite the same but it is almost plug and play with your code. Here is the IMU I am using http://www.dhgate.com/gy-66-idg655-adxl335-module-5dof-module-twin/p-ff8080813c8a9352013d15d2c35b77d9.html
Have just added a link to that IMU to my Instructable. Thank you very much for finding it. Many people are having trouble getting hold of analog IMU's so this will help them a lot. <br> <br>John
Dear Mickydee <br> <br>I have just bulid the hardware for self balancing electric skateboard using Arduino Uno to control with 5DOF IMU (IDG655 ADXL33). I have encouter some problems: - <br>1. When I tilted the scooter too much, it will fly off. Is there any code in the program to prevent the scooter from flying off if it is tilt too much? <br>2. When the scooter fly off, it took quite a bit of time to &acirc;€˜recover&acirc;€™ to it balancing position if I were to tilt it to the opposite direction. Anywhere in the code where I can change to have the scooter tilt back faster? <br> <br>I am using code from XenoJohn from instructables website. Please help. <br> <br>Thanks.
After half an hour reading your instructables, I have to say you're awesome in Thai. สุดยอด!
Hi Mickydee, <br>Sparkfun IMU Part # SEN-11072 is retired now 03/18/2013. I'm very appreciated if you have other to replace it. Thanks
Nice job, sir ! I read the book about the development of segway which was very descriptive with all aspects of it. There's a lot of work on something like this and I can only say that you are awesome !
Thank you very much. I appreciate your thoughts. This is a great community, and every one seems to work together. This is my first attempt at a self balancing project, and I owe most of my success to Xenon John and his balancing skateboard and his software. <br>Mickydee
Hello Mickydee, <br>I read your project and very impressive to me. Today is 03/14/2013. I can not find 5 degrees of freedom IMU from SparkFun. I already have wheel chair motor, Arduino Uno, Sabertooth 2X25 etc... Can you help me, where can I find 5 degrees of freedom IMU or something replace it. And the code to work with. <br>Thanks, have nice day.
Xenon John has researched this problem and says that Sparkfun is now stocking a replacement IMU Part # SEN-11072. He says that it will work perfectly with the existing code. I am going to order one and try it out. <br>Good luck on your project. I am working on an improved machine and it should be ready soon <br>Mickydee
so very cool!! I need to learn about arduino so I can make stuff like this - especially for my aging parents. They'd be way too proud to use a wheelchair but this might just be the thing...
Why is the motor driver so expensive, and why can't you use one under $30 like the official motor shield? <br>
These motors draw around 15 amps at peak. Even if you use the 350 watt Chinese motors you will have the same problem. The cheaper shields will only tolerate around 2 amps. Also the Sabertooth has so many options that make your life easier. I thought about building my own drivers but the parts alone would cost almost as much. <br>If you are going to build this I would suggest you bite the bullet and buy the Sabertooth.
WOW! <br>realy good <br>
Congrats on being a finalist!
Great job - You've also inspired me (69) to post some of my projects!<br> I also have a wheelchair I got at a garage sale with very similar wheels and motors to yours and would like to construct a &quot;Sitway&quot;. However, when I turn the wheels there's about 5 degrees of &quot;slop&quot; before they engage the motor/gearbox, and I'm thinking that there's no way it can maintain stability with that much slop. Do your wheels have that much slop?<br><br>Eric
I have some &quot;slop&quot;, but not as much as you are experiencing. Mine seems to achieve a stable balance. <br>I built this thing as a low cost project, and that is the reason for using the used wheelchair . If you want to get tighter balance you should use a chain drive system.<br>I have thought about repacking the gear box with heavy grease to smooth out the<br>gear lash. I plan to rebuild mine using a chain drive system and larger wheels.<br>This was my first attempt at building a &quot;self balancing&quot; vehicle, and am learning as I go. It's a fun project. Go for it. You wont be sorry
Try using the 300-400 watt motors from china that come with a 6:1 (approx) reduction gearbox and chain sprocket built in. <br> <br>http://www.ebay.com/itm/24V-350W-Electric-Motor-W-Gear-9T-Sprocket-24-Volt-350-Watt-MY1016Z3-/180734270314?pt=Motorcycles_Parts_Accessories&amp;hash=item2a149a1b6a&amp;vxp=mtr <br> <br>Part code number is MY1016Z3 <br> <br>Almost zero backlash in the reduction gears. <br> <br>The chain sprocket keyway eventually works loose as not really designed to be going from forward to reverse all the time. In the end I took end plate off and welded the chain sprocket on using burst of MIG, then sprayed it with my anti-spatter spray to cool it, had a cup of coffee and left it for 30 min to cool, then another small burst and so on, to make sure I did not cook the outer bearing. Works fine now. This way you can use a bigger wheel without resorting to a massive chain sprocket on the wheel. <br> <br>
Once you are moving along the slop becomes less relevant as more like varying the trottle to make a bike do a wheelie.<br><br>Is an issue when balancing in one place. If you set the gain too high machine will start to oscillate as gyro detects the sudden jolt as gears move (backlash). Can still make it work OK but with lower gain the machine feels a bit &quot;mushy&quot; as you ride it. Can sometimes overcome problem by having low gain around +2 to -2 degrees of tilt for example, then increase the gain a little as tilt angle increases (and so after any backlash from any recent change in direction has been taken up by the gearbox) to tighten up the ride.<br><br>Best solution would be motor with a toothed belt drive to wheel. Working on something now but not as easy as it sounds.
Good news.<br>Sparkfun have just released an updated version of their 5dof analog output IMU.<br><br>IMU Analog Combo Board - 5 Degrees of Freedom IDG500/ADXL335 <br><br>Part number SEN-11072<br>So, everything is OK again.<br><br>John
Beautifully written sir, you get my vote. I generally just browse the site looking for ideas to get the brain ticking over, but yours was enough to make me log in and vote. The combination of a beautifully built device, fully specced out parts list and an instructable that presents a complicated device in a completely accessible manner has me truly impressed, and a little envious! <br><br>(It was the 45 degree braces and slotted motor mount holes that really caught my eye though. Hallmark of an Engineer. I will be keen to see your next instructable!)
This, like so many balancers, use the 5 Degrees of Freedom IMU that is no longer available. Has anyone tried the replacment IMU that Sparkfun sells
Clone of Sparkfun 5dof IMU found on ebay:<br><br>GOOD NEWS EVERYONE<br>This clone IMU on eBay looks exactly like the SparkFun 5dof analog output IMU that they have now discontinued. Price is good too.<br><br>http://www.ebay.com/itm/190478609162?ssPageName=STRK:null:IT&amp;_trksid=p3984.m1542.l2649<br><br><br>This may help a few people.<br><br>John
Hi,<br>For anyone who wants to take the plunge and have a go with a 6dof Sparkfun DIGITAL IMu I have just attached some code to page 53 of my skateboard instructable. Not fully tested yet but all the values it gives seem smooth and about right.<br><br>http://www.instructables.com/id/edit/?instructableId=E3C1NR6G6MPQ5EM#instructableId=E3C1NR6G6MPQ5EM,stepId=SZGO7T3GZKE1JXL<br><br>John
I think Xenon John has looked into them, I don't know how far he has gotten.
81 years old - you have inspired me - I am 70 going on one more - I have been lurking on Indestructibles for a long time - but your very advanced project has given me impetus to do a project - I have a very small compact shop with a Lincoln MIG, 200 amp DC welder on a trailer, a rebuilt metal lathe and sundry tools - I have some tools, an Arduino Uno and some ideas - if you can do it at 81 I certainly can do it at 70 - thanks for the excellent project and the inspiration..
Sounds like you have the makings of a great shop. With those tools you can make just about anything you want. I love to tinker and this hobby keeps me well occupied and out of trouble. You will find a world of help from the instructable members that watch this site. I have been helped out many times by the many members. <br>Go for it!!! you wont be sorry. Let me know if I can be of any help to you.<br>Your friend<br>Mickydee<br>
This looks great.<br><br>It balances very well. I absolutely agree with letting the machine balance you. It actually helps on the skateboard to hold your legs rigid. Beginners do better on it than surfers who instinctively try to correct what it is doing.<br>Alternative to holding onto the stick would be to make a seat with a full chair back, like a racing car seat, to create the rigid object (i.e. the rider) then use a hand control to adjust the target balance point of the balance algorithm to make it go forward or back. Working on code for something like that now.<br><br>Also check this out - works on this principle:<br>http://www.youtube.com/watch?v=ik8RpV8w08M<br><br>Meanwhile, I have improved the code quite a lot on my skateboard page if you want to try out / modify the updated version.<br>Best wishes<br>John<br><br>
Thanks John<br>I would love to use a hand joystick to control this thing. I have salvaged the controllers from two old wheel chairs that might be used for this purpose.<br>I will try your new code and see what happens<br>Mickydee

About This Instructable


368 favorites


Bio: My name is Roland MacDonald, my friends call me Mac I am a retired but not bored engineer My great joy is my workshop, a ... More »
More by mickydee: SITWAY 10 HP Hovercraft RC Riding Lawnmower
Add instructable to: