Dexter Industries BrickPi Advanced

I'll start my review with a disclaimer. I am not a robotic engineer or an electronic engineer, so running robots is not my specialty. I have been a software engineer for about 20 years and have used Linux, C and Java for most of that time. I'm familiar with the NXT and EV3 in general and have used the Lego language for both platforms.I had purchased the BrickPI along with an 8 cell battery pack and had intended on using it with an NXT 2 kit along with a EV3 IR sensor. Setup was quick and easy, I found the online setup documentation to be very good. I had the unit put together and running a simple program in under 30 minutes.After this initial experience, I though "this is going to be easy". Once I started down the road of trying to get the robot to do something useful is where it went downhill.I had started using an older Raspbain image I already had on my Pi. After my initial set of problems detailed below, I moved to the Dexter Raspbain image, but it provided little help. I had been providing adequate power with both the AA battery pack and a mobile USB battery. I had later switched to a 12v 1.5a wall wart for testing.My first issue was the color sensor was displaying bad values. I finally found a workaround, restarting my program until the color sensor started on the correct value, and then it would work correctly for the duration of the running program. This was an okay workaround, but ended up being a pain. I had reached out to the Dexter BrickPi forums for help and didn't find a solution to my issue. I tried both EV3 and NXT2 color sensors and neither worked reliably. Both of the tested sensors worked perfectly with the Lego bricks.The second issue, and ultimately the reason I returned it, controlling the stepper motors with any type of accuracy was extremely frustrating. I first started with the community authored Java API. It was easy to use, but could not provide accurate control of the motors. Yes it can start, stop and control the speed, but any attempts at controlling the stop angle at < 360 degrees was impossible.I then switched to the C API, since it's my second favorite language. Working off one of the sample programs, I was also able to control the basics, but could not make any accurate movements here as well, in addition, the encoding values reported my the motors was just off and delayed. The color sensor values were also off with C as well.Now I seemed to get the most out of the Python libraries. I had setup a nice system of using Eclipse on the Mac and then a shell script to scp the programs to the Pi and then run the program. Though I had the most success with Python, I still could not accurately control the motor based on the encoder values I was returned. I could stop the motor at what I though was the correct encoder value, wait 2 seconds read the encoder again and the number would be different. Very frustrating.I found various posts on the BrickPi forums about the same motor issues. Some community members had attempted to solve this issues with custom Python forks of the Dexter code, but none of these forks seem to allow me to do every thing I wanted. Using NXT along with EV3 parts.I did run into a pdf for a robotics course somewhere in the UK. The robotics course provided the students with an updated C library for accurate motor control using the Brick Pi, specifically advising the students against using the Dexter provided drivers (go figure). I managed to pull down the image linked from the PDF and it worked perfectly. Great motor control and accurate encoding values, but no EV3 sensor support so no good to me. :(The Brick Pi community has waned since the kickstarter and you'll be lucky to get a reply within 24 hours.The Brick Pi cost is excessive for the components on the board. The boards firmware needs to be a lot better and a richer better documented API. I'm not asking for full html docs for the API, but function descriptions within the BrickPi.py file itself would be nice. The BrickPi will work for you if don't need any type of precision. The provided sample projects are proof of that. Drive this way, drive that way type of stuff. I can honestly say I gave this thing the old college try. I spent the better part of my evenings for 3 weeks to get this working to no avail. 3 different images and 4 different APIs.I've since switched to an EV3 brick using the lejos java libraries, and I could not be happier. Accurate control, excellent documentation and a very rich API.

Works great considering a second for my other son. We were able to build a Robot the first night that we could remotely control - more of an ROV but having it connected to a real computer - the raspberry pi makes so much sense. If you are technically savvy are willing to work with your kids this can be a great tool and project for them to learn python. If you have been able to get results with your raspberry pi, this is a natural progression.Within a few days using the sample code provided by Dexter industries on their image for the raspberry pi we had a prototype that the kids could work from that provided a better more intuitive keyboard control. A Remote web cam with the ability pan using the rover and tilt using a servo and a working arm that open and close a claw. The webcam has Streaming ability using mpeg-streamer.Truly Sweet.P. Pinto

I've enjoyed using the brickpi.  As a beginner learning python, this has been awesome to program in.  There are a lot of examples for using each of the lego sensors.  The website has step-by-step instructions for getting started.  I haven't done a lot of programming before using the brickpi, the examples have really helped.  Plus I can add web stuff to this pretty easily.  With a wifi dongle, I'm controlling the robot over the internet. I contacted Dexter Industries with several programing and technical questions and received a reply from the company within 48 hours each time.

I had purchased this product believing Dexter Industries' claim that the shield could use AA batteries to run NXT motors and power a Raspbery Pi Model B. However upon testing the shield proved that it does not manage power properly. When as few as two motors meet any more than minor resistance, the BrickPi handles the extra power consumption by giving the Pi less power. This causes the Pi to crash and reboot rendering the BrickPi useless for such hobbyist robotics purposes. This was a disappointing purchase.

I wish I had done more research before dumping nearly $100 on this. The unit ships with standard Dexter Industries instructions (Hint: Nothing. They include nothing) and support is scattered and outdated. If you have older NXT stuff it might be a fun toy to tinker with, but it can't be taken seriously with so little support and infrequent updates.The included "case" is heavy, over-sized, and doesn't properly support the RaspberryPi. The BrickPi board doesn't sit securely on top of the RaspberryPi. Not a great setup for something that is likely to move and have things plugged and unplugged often.

Haven't tried it yet but it appears to be everything I expected.

Good delivery time and conditionEasy use of documentation and startup info.Now i can build robot with raspberry, while my son make it with mindstorm computer.We can make two robots and make a challanges etcI'm very happy with the project. I was looking exactly for this kind of functionality.So my dream about this came true.Now my son can learn python easily. Thank you guys, you're the best!!! Please dont stop to build more.thanks for so cool product

Love this product. Plan on using this to teach scratch to 4th graders. Excellent documentation and easy to follow instructions (not sure why one of the reviewers was negative about this). Forum is very helpful - great support.