Smart Robot Car Chassis Kit with UNO R3 Module - Educational DIY Toy, 2WD with Battery Box and Speed Encoder for Tracking Obstacle Avoidance - Designed for Beginners to Learn Programming

I'm giving this 5 stars for the price and because my kit actually did come with pre-soldered motors, as well as a mini-CD with sample code and a video showing how to assemble the kit. I ran into two minor assembly problems: 1) The holes for connecting the caster wheel were too large (it slipped right over the nuts that were supposed to hold it on). I didn't have any washers of the right size, so just I used a little bit of cardboard from a tissue box to fasten it. And 2) the battery pack didn't have the extra wires coming off the plug, so I had to chop the plug off. Neither issue was bad enough to drop my rating. I still think this is a very nice kit for the price. What I really like is that almost all of the parts will be useful in future projects.

As others have pointed out, this kit isn't exactly perfect. You will get all the parts you need to build this robot but no part of the assembly will be without a little challenge. I would not recommend this kit for a beginner to Arduino or to electronics. Nothing will work right from right out of the box. Someone with a little experience can massage this kit into a fun, working robot. If nothing else, you get a lot of good parts for the price in this kit. First I'll share some of the assembly challenges I experience. The Arduino and the motor controller can only be secured to the acrylic with two screws each. If you want more than that you will have to drill your own screws. For now I've opted not to and it holds together well enough. The battery case is meant for six batteries and only one hole lines up on the acrylic. I got around this problem by using velcro to hold the battery pack in place. The servo mount already had the servo arm mounted inside it but the screws were installed from the wrong side. The included instructions suggested a "fix" of installing a screw through the center of the arm and into the servo shaft which will work but I chose to also fix the incorrectly installed screws. For all this hard work you will still find that the screw holes in the acrylic do not quite line up with the screw holes in the servo base. Others have noted that the instructions for wiring the motor controller are incorrect. I found that to be the case in my kit too. However, where others found that the problem was the numbering of the analog pins was off by one, I chose to use the digital pins and reserve the analog pins for future use with actual analog devices. For assembly, the last problem I had was the instructions calling for connecting the power switch between the Arduino and the motor controller. This is not ideal as the result is that the Arduino board is always on once you have installed all the batteries. I cut the red power lead of the included barrel connected and connected the switch right after the battery pack so that once the switch is flipped the whole robot turns on. Others have complained about the rear caster needing washers or not quite lining up. Funny, but that was the only part of my kit that was without problem. Another reviewer, Perspicacious Consumer, pointed out that the ultrasonic scanner is "crappy." I agree. As for the included Arduino sketch, it stinks. It is a very poorly written piece of code that will have to be edited just to get the kit to work. At bare minimum you will either need to adjust the analog pin connections as pointed out earlier or you will need to change the pin values in the sketch. Also as Perspicacious Consumer pointed out, unless you enable PWM by uncommenting the analogWrite commands, your robot will run at full speed. I have hardwood floors in my house so I need to run the motors just barely above stall speed or the robot "peels out" by spinning its wheels in place without grabbing traction. There is one last significant problem I experienced with my kit. No matter what tricks I tried, I could not get the left and right motors to turn in sync resulting in the robot veering in one direction or the other. The kit includes shaft speed encoders but for some curious reason it does not include the photo-optical speed sensors needed to read the encoders. I've ordered a pair of speed sensors and will update this review with my results once they are installed. Despite all I've mentioned above, this kit is pretty fun and I've already started writing a custom library for it. It has a lot of potential and room for refinement and additions but it will require a little know-how and perseverance to get it going.

This is a great, low priced robot kit. The kit doesn't come with any instructions or code so if you are looking for a step by step, Instructable style, kit this is not the kit you should be buying. This kit is a bunch of independent pieces put together into one package then sold as a "kit" and as a result unless you drill additional holes in the robot chase you are not going to get all the screw holes in the PCBs to align with chase holes. In all this is a fun few hours of layout, assembly, piecing together, and coding.

I'm a geek. I build things, I modify things, and I'm not new to Arduino. I wanted something that I could learn more with, and I chose this kit for the included parts and the low price. I used the instructions in the video just to see the contrast between those and the ones linked in others comments. The video and instructions that come with the product are no good. Was able to use instructions mentioned by other reviewers. With it all done, I uploaded the code and powered it up. It didn't work as expected, and it wasn't avoiding any obstacles. I grabbed another arduino and and used a test sketch, and found that the ultrasonic transducer didn't work at all. I checked a few solders on it that looked sketchy but to no avail. It's a dud. I originally thought about getting one of these kits for my nephew but with worse than terrible instructions and bad parts, I can't. I'll have to spring for a more expensive kit with better instructions and some QA for parts so I don't send him broken stuff! Update 5/13/19: The Arduino clone that it came with died. I ended up replacing the motors with continuous rotation servos and wheels that slowed this thing down to reasonable speeds. Save your money, buy a better kit, or else buy the parts separately and scratch build.

It comes with all the parts listed, and instructions on DVD+R, which you absolutely need. There's an instructional 18 min video that is very helpful, you'll need to decompress the .rar archive with WinRAR or Archive on Mac, then you will have the .mp4 video file. Though I have ~4 yrs experience with Arduino and others, I think others with less experience should be able to complete the project. The hardware assembly is the easy part, and fun. Because they upgraded the kit to a 6 battery holder (the instructions use a 4 battery holder), you will need to drill one 1/8" hole. Though the motors have the leads soldered (nice), and the switch is also soldered (unlike in the video), however, you will need to solder two wires together, the switch red wire to the battery red wire. As someone else noted, there's a mistake in the instructions: The red motor driver board (L298N controller) IN1, IN2, IN3, IN4 should be connected to A0,A1,A2,A3, NOT A1,A2,A3,A4. Pins A0-13 are referred to as pins 14,15,16,17 in the program code given. In the code, you will benefit from uncommenting the AnalogWrite commands, to pins 5 and 6. Check out instructions for the L298N controller online, remove the jumpers near A1 and A4 and use the AnalogWrite commands to control the speed of the motors. Full speed is uncontrolled. The ultrasonic detector is crappy and doesn't work well with rough cloth surfaces (couch, clothes). This is a great deal at ~$20, I paid more 4 years ago for a rover without the ulrasonic detector. The code works but is poorly written. Combine these parts with other fun stuff on Adafruit or Sparkfun or Amazon.

I have purchased 2 of these kits. Just can't beat them for the cost. The instructions are useless. Neither kit I purchased had the battery case given in the instructions, which messes up parts placement on the chassis. Good instructions and code are given in the links in the Questions section of the product descriptions on Amazon. This would not be a good kit for a beginner - on the other hand, it is challenging and fun to sort/search/learn your way to getting this working. I recently bought the Lafvin kit for just a few $ more. Much better instructions and the code works.

As others have mentioned, there are a few bugs with this kit. The issues I found are as follows: 1 - The holes in the caster are too big for the offset mounting hardware. 8 3M washers fixed that nicely. 2 - Battery holder doesn't have the correct holes drilled. A small drill fixed that. The mounting screws are too small for the holes, and more washers fixed that. (It really should have some flat head screws instead of cap screws so the end batteries will fit flush with the battery case.) 3 - The battery case wire does not have the pigtails to wire to the motor control board so I chopped the end off, spliced in to the wires keeping red to red and black to black. I soldered the wires to make sure I had a good connection and finished it with heat shrink. 4 - The drive motor wiring diagram shows A1 through A4 in use for IN4 - IN1. That would be okay, however the test code that comes with the kit uses pins 14-17 which means they really intended the connections to use A0-A3. The first time I powered it on, it was spinning in a lefthand circle. 5 - The testing code had to be modified to the way my motors were turning. I ended up with pinRF=14, pinRB=15, pinLF=16, and pinLB=17. Once the wires were switched to A0-A3 and the left/right forward/back changes were make it worked. This kit was fun to build, and the video was quite helpful. A picture of the sensor shield with the wiring completed would have been helpful. It was quite easy to find documentation on the web for the motor controller and sensor shield. The biggest problem I had was determining that A0 on the sensor shield matches pin 14 in the code. The testing code will prove that the parts are working, but it is just a jumping off platform. Now I'll find tune it's operation and possibly add additional sensors. There are huge numbers of possibilities, which is the whole idea! I plan on using these for middle school students after they have mastered some basic skills with the Arduino board. The price point makes it much easier to give each student their own with which to work. The minor issues with the kit are more "learning opportunities". HIGHLY RECOMMENDED!

This has wasted so much of my time it's actually insane. I ordered this last year, hoping to use forced downtime to learn a bit more about electronics. I come from a software development background, and such wanted something relatively cheap and easy to get started. By the time I finished building it, it was no longer the cheapest option, and it is anything but easy. I later learned that is kit is almost standard as a teaching tool for schools, not because of its price or convenience, but mainly due to how flawed it is, for troubleshooting. and boy, are they right. I didn't realize it before ordering, but this 'kit' requires soldering, the instructions are for different parts, and several wires and screws were missing. The instructions are terrible, and I quickly bounced off them and went looking for others, since they're literally incorrect. At some point I lost the CD, and had to use a pdf found in the Q&A section. The build is.. relatively easy, but is hamstringed by many, many poor decisions, including missized holes, a power switch that only controls power for the motors, a battery pack that's too big and can't be secured properly, and in my case, a DoA ultrasonic sensor (I think), which, somehow, lights anything plugged into it on fire if you wait long enough. Since I lost the instructions, and they're not available anywhere online, I ended up having to find/code on my own, which sucked, and since either the ultrasonic sensor or the sensor shield board is lighting things on fire, I can only run code with no vision.. which is basically useless. Overall, the best use I could suggest for this kit, is as donor parts for something better. Because oh my god. it literally lit itself on fire. what the hell. EDIT: I was able to source a new ultrasonic sensor, so I can verify mine was not only DoA, but had a severe short.