I like the Lego modular system, especially Lego Technic.

I have a collection of Lego Technic Vehicles, i.e. Road Rally V (8225), Rough Terrain Vehicle (8270), Formula 1 Race Ca r(8808), etc. These small Lego vehicles could be upgraded to use (rare to find!)  Electric Motor Kit (8720) to drive the vehicle.

I want to challenge myself to incorporate Arduino, XBee into my R/C Lego car design.

I want to do something different!

I do not want to buy commercial available toy R/C (Radio-Controlled) car and modify it to used with XBee and Arduino. (I already did that successfully, Processing Controls R/C Car with XBee modules.

I want to do something similar to an NXT or RCX Mindstorm system with my R/C Lego car design (At the moment, I could not afford either NXT or RCX.)

I want to use parts that are available at hand.

So, I end up designed my very own R/C Lego Car by reused the parts from:
- Lego Steering System from 1996 Lego Car Kit (#8207 Dune Duster)
- Motor with worm gear from Electric Dragster from Middlesex University electric science series) ,
- micro servo from my other diy robot.
And built an Arduino compatible with simple motor driver IC (L293D) PCB, with wireless XBee breakout board compatible receptacle.

 And here is how I created it!

Note: See more photos of my R/C Lego and video in Step 10.

Step 1: Parts and Tools

Lego Technic Bricks

Following is the list of Lego Technic parts that I used for building the car.

When I started to do this project I thought about using the bricks from my Lego cars collection. But I changed my mind so I did some bid on ebay so I could get some more steering system to work with. I chose to bid on the almost complete vehicle, or those without the construction manual, to get them cheaper than the complete kit.

If you want to do this project you could use the differenct color for the car. I have no choice, because the red brick were available when I got started. Later I got some other color from the bid on ebay.

Note: The number in the bracket is the Lego's Design ID.

3 no. - Plate 2x8 (#3738)
2 no. - Plate 2x3 (#3021)

8 no. - Brick 1x2 (#3700)
8 no. - Brick 1x4 (#3701)
3 no. - Brick 1x6 (#3894)
2 no. - Brick 1x8 (#3702)
2 no. - Brick 1x12 (#3895)

1 no. - 1x2 Brick with Horizontal Snap (#2458 not shown in the picture)

2 no. - Cross Axle 3M (#4519)
2 no. - Cross Axle 6M  (#3706)
1 no. - Cross Axle 10M (#3737)

2 no. - Axle Conn Ridged & Hole (#6538b)
10 no. -  Connector Peg with Friction (#3673, 6 grey, 4 black)
6 no. - 3M Connector Peg (#32556)
6 no. - Bush for Cross Axle (#6590)
2 no. - Liftarm Triangle Thin (#2905)

Steering Kit
Steering Gear Holder(#2790)
Steering Rack (#2791)
Steering Rack Top (#2792)
Steering Rack Bracket  8 pin Plate T37 (#4262)
Steering Arm Drop Link (#4261)
8 Tooth Gear (#3647)

1 no. - Axle 3 with Stud (#6587)
1 no. - 1/2 Bush (#32123)
1 no. - 1x4 Flat Tile (#2431, not shown in the picture)

Wheels and Rims
2 no. - Tire size 30.4 x 14 VR (#6578)
2 no. - Wheel size 30.4 x 14 VR (#2994)

2 no. - Tire size 43.2 x 22 ZR (#44309) 
2 no. - Reinforced Rim with no pin holes 30.4mm D x 20 mm (#56145)

9g Micro Servo (T Pro SG90)
This servo is controlling the front wheels turn.

I got the motor with the worm gear and enclosure from Electric Dragster Kit by Middlesex University.
This motor is driving the car forward and backward.

Arduino or Arduino compatible (I used DIY Arduino in this project.)
L293D (or SN754410) motors driver IC
XBee module
Xbee breakout board (I used XB-Buddy Basic Kit, Jameco's Part no. 2163680)
PCB (approximately 2"x3")
Hook up Wire

Super Glue
X-ACTO Knife
Sand paper
Hand Drill & bits
<p>very cool indeed. love lego hacks</p>
Hey, Legos are my thing! Great idea,sath02.
legofreak86, <br>I can tell how much you love Lego ;) <br>Thanks for the compliment! <br>
Great 'ible sath02! My 8 yo son saw this over my shoulder and put it on his Christmas list. I sourced one of the Lego Technic kits, as well as the 9V Technic Motor kit, all new, all from the '90's (eBay is awesome), and I got all of my Arduino bits from Sparkfun. I will be posting my first 'ible from this. Thanks for the inspiration!
Thanks. <br>So your son is going to get an early Christmas gift this year! :) Good for him! <br>Great! Looking forward to seeing your first instructable. <br>If there is anything I could help, please let me know. <br> <br>
I was think more over to the power functions side but this works too :D
This is my first Lego Technic build. I do not have power functions kit. So I used Arduino instead of RCX or NXT, used motor controller IC, and servo with it. <br>It worked well.
Good! :) <br>Gone to the Blog: <br>http://faz-voce-mesmo.blogspot.pt/2012/11/back-solve-calculos-de-engenharia.html
Thanks, Edgar. <br>You're so kind!
Well, I like sharing good stuff. :)
This is really cool! Can I use an old RC car for the electronic components?
JonnyBGood, <br>Thanks! <br>I can not give you &quot;Yes&quot; or &quot;No&quot; to your question! It could be either one, it depends. <br> <br>My R/C Lego Car only used the rear motor and the worm gear with enclosure from old electric dragster kit that did not have the front steering system. I have to used the existing Lego steering system from an old Lego Car Kit. This was easy enough, since I only did the modification to the motor from the electric dragster kit. <br> <br>If you want to use the old R/C chassis or frame without modification, then build Lego bricks and beams around or on top of the old R/C chassis or frame. Then add Arduino &amp; XBee and use Processing to control it. If that what in your mind, please look at my instructable: <br>http://www.instructables.com/id/Processing-Controls-RC-Car-with-XBee-modules/ <br> <br>If you don't care about your old R/C car any more, you could cut out the front steering system and rear motor with the gear train. Then builds Lego bricks and beams as the frame (like I did), and modify both the front steering system, and rear motor driving system, by doing something similar to Step 7 in this instructable, to fit the Lego frame and both front steering and rear driving system together. <br> <br>Hope this answer your question. <br>
i have to give you props for making a cool idea come alive. this along with the mindstorm bots is probably the most advanced vehicle made from legos on the site. i hope that this section will move away from those droll minifigs and move up to stuff like the more complex technic vehicles.
Thanks for the kind words. <br>I am hoping to see other Lego enthusiasts out there build thier own R/C Lego, and may be we can have a race! <br>That would be fun, wouldn't it? <br>

About This Instructable


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Bio: I am Electronic Visualization Artist. I look at things through the Looking Glasses.
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