PiCrawler

I got this cause I wanted a robot kit as I need to learn python for a larger robotics project. I really only learn hands on so I need a tool to see tangible results. I didn't get the one with EZBlock so I cannot speak to how well that works. There is a lot of good stuff in this kit for the cost, especially comparatively to other kits. You also don't see too many kits with legs outside of the bumbling two leggers for a good price. The instructions are fine, but you need to work with both a browser open and the assembly leaflet. I feel the leaflet could have a bit more information on it and some "Do this like this OR ELSE" notes as I had a couple times I had to do partial disassembling to adjust leg positions. Also the plastic rivets, its good they come with extra as a couple exploded. I feel like there's a nyloc nut screw combo that could do better. There are also a few repeating difficult screw locations that a better/different/wider cutout could ease some of the pain, ESPECIALLY if you have to do any corrections. Overall though, the build, imaging, and calibration was easy enough once I found what I did wrong. A good note is that calibration can only correct servo>leg position so far, so the position you attach the legs to the body at is real important. The online instructions for getting going, and the explanation of the code and how they did each bit are great. Not a ton of results online for troubleshooting though. I was able to get through it from my IT and 3d printer building experience but I think it could benefit in the long run to have more than "Maybe zero the motors?" cause mine were perfectly zeroed and I still had calibration issues. Also, on the Python script leg calibration, the legs move when you change the numbers, but not all the time. A great many of the inputs are missed, so you kind of have to measure, change it a couple steps, and then save and run the calibrator again so they position properly. Overall though, not enough to take it from a 5 to a 4 star imo.

It's a great kit, our issues mostly come from using Raspberry Pi 2B instead of the newer boards. It needs a bluetooth connection which we had to remedy by getting a dongle instead. Once it's installed, it works wonderfully. Good learning process while building this robot with my kid. The company was supporting us as well while we were having problems with it. We are still exploring more things about this robot, I think it's pretty amazing but its tough for beginners, especially if you get stuck on some aspect during the assembly. We got stuck at trying to get the servos reset to the origin position, had to flush the OS and run the python codes instead. Which fortunately was provided by the company as well. It's a pretty awesome robot kit.

This thing is a lot of fun, and Sunfounder support is extraordinary. They are in China, so there is a 12 hour time difference, but they respond promptly. Some stuff you should know. There are several versions and revisions to the Crawler, so a lot of the things you see on-line are not applicable to the current model and this can be really confusing. For instance there is a lot of chatter about having to buy special batteries, but the current model includes a proprietary battery pack. Assembly is not too bad - the instructions are VERY clear, but there are a lot of small screws, so a lighted magnifier and steady hands are a must. They give you all the tools you need, except tweezers. There are some compatibility issues with the Raspberry Pi5 and the Trixie OS. I have a Pi5 and everything works, but I had to install Bookworm to get everything to function. There is a graphical tool similar to Scratch for programming, but it doesn't work with the Pi5, so you'll have to use Python. It ships with a Robot Hat (V4) which draws more power than the one in the Pi-Dog (V5), so the Pi5 gets starved for power and sometimes objects to this. Sunfounder will sell you a V5 Robot Hat for next to nothing, if you contact them. The servos have some plastic gears and I busted 4 of them when I dropped the Crawler. Again, Sunfounder was super-responsive, shipping me some upgraded replacement servos at almost no cost. With the Pi5, some of the Crawler Library functions (like sound) don't work unless you run the Python program as a super user ("SUDO") If you are starting from scratch, I'd recommend getting a Pi4 and installing Bookworm rather than Trixie. It's a fun device. There is very good documentation (which you have to download and print yourself), and a ton of sample code. My only criticism is that I spent a lot of time spinning my wheels because of the Pi5 and Trixie issues. In the absence of that information, you never know whether your errors are truly yours or not your fault. The support is so good, that it pretty much overrides my other concerns. The folks at Sunfounder seem to be really friendly, responsive and helpful.