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After having spent some time recently looking at top-down AI, I thought I would spend some time looking at bottom’s up AI, machine learning and neural networks. I was pleasantly introduced to @mikea’s core.matrix at Clojure Conj this year and wanted to try making my own neural network using the library. The purpose of this blog is to share my learnings along the way. What is a neural network? A neural network is an approach to machine learning that involves simulating, (in an idealized way), the way our brains work on a biological level. There are three layers to neural network: the input layer, the hidden layers, and the output layer. Each layer consists of neurons that have a value. In each layer, each neuron is connected to the neuron in the next layer by a connection strength. To get data into the neural network, you assign values to the input layer, (values between 0 and 1). These values are then “fed forward” to the hidden layer neurons though an algorithm that relies on the input values and the connection strengths. The values are finally “fed forward” in a similar fashion to the output layer. The “learning” portion of the neural network comes from “training” the network data. The training data consists of a collection of associated input values and target values. The training process at a high level looks like this: ...

One of the wonderful things about being a technologist today, is to be part of an industry that is bubbling over with new and exciting things. It can be exhilarating and overwhelming. How can we try and do all these great new things? Of course, it is not sensible to simply drop whatever you are using and continually chase after the newest tech. Nor is steadfastly staying in one place and refusing to accept that there is a better way of doing things. The challenge is to absorb, identify, and synthesize both good of the what we are currently doing and the new stuff too. We want to embrace and continue the good things that are working for us and reach for the new technologies that will propel us farther in the future. ...

I really love the London. I have only been once many years ago, but I was enchanted. Here is a partial list of my favorite things: Ducks in Regent’s Park Tea Rooms The Food Hall at Harrod’s The British Museum English Breakfasts The way the British put an extra “r” in phrases like “vanilla in it” As you know, I also adore Clojure. So I am absolutely thrilled to combine the two. ...

How to Control Multiple Drones with Clojure The clj-drone library now has multi-drone support! You can now send multiple drones commands, receive their navigation data, and even have them perform their actions autonomously with goals and beliefs. It takes a bit of extra setup to control more than one drone. We need to assign them each an ip and get them talking as an adhoc network. Jim Weirich creating a neat little script to run on the drone to do just this. Here are the instructions: ...

Why do you devote time and participate in the community? Why do you devote time and participate in the community? I find joy in coding and making things. I want to be around other people who feel the same way. Why? Because I want to be inspired by others and learn from others and hope that they are inspired and learn from me. Why? Because ideas and learning doesn’t happen in a vacuum. There is something magical about the serendipity of human interaction and that needs a community to take place. ...

Lately, I have had the pleasure of speaking and sharing my experience of programming AR Drones with Clojure. However, doing live hardware demos has not always been a smooth ride. In fact, it can be fraught with peril. I thought that I would share some of the tips and tricks that have helped me, as well as help make you aware of some potential pitfalls. Traveling with the AR Drone Do you need to take your drone with you on the plane to the demo? The box that the drone comes in is a very nice carrying case, however it is too big to take on as a carry-on. I found that taking the hull off, and packing it into a plastic box worked well. It was small enough to pack under the seat of even the smaller planes. I took the battery out and packed it in my checked luggage. ...

Preface: A Gentle Obsession About a year ago, I picked up John McCarthy’s paper on Elephant 2000. I have to admit that I only understood about 10% of it. But I was so intrigued by the ideas that it sent me on a quest. I re-read it numerous times, slept with it under my pillow, and finally decided that I needed to read his other papers to get an insight into his thoughts. I began a considered effort with Seven McCarthy Papers in Seven Weeks. It ended up taking about three months, rather than seven 7 weeks. Again I came back to Elephant 2000. I began to understand more as other ideas and concepts sunk in, like ascribing beliefs and goals to machines. But to really explore the ideas, I really wanted to try to implement parts of Elephant in my own programming language. The problem was, having no formal training in computer science, (my background is Physics), I had never created a programming language before. The stars aligned and I found the Instaparse Clojure library. The result is Babar, a language designed to explore communication with machines via Speech Acts. ...

Creating your own programming language with Clojure and Instaparse is like building rainbows with s-expressions. The Instaparse library is an elegant way of building executable parsers trees with pattern matching and standard EBNF notation for context-free grammars. Since this is my first foray into parser trees and grammars, I thought I would share my learnings in this post. Starting with a Single Word Let’s start with the simplest example: a number. When we start up our REPL in our brand new language, we want to be able to enter an integer, and have evaluate as an integer. ...

So I am in the midst of doing something a bit crazy and a bit wonderful at the same time. I am opening a coworking space in Loveland, OH called Locolo. It is a bit crazy because it has very little chance of being profitable, I have very little free time in my life to devote to such an undertaking, and I work full-time with awesome folks so I wouldn’t even be there during the day. Despite these very pragmatic reasons for not doing it, somewhere along the way I said F*** IT, I am doing it anyway. This blog post is an attempt to explain why. ...

Clojure is fun. Flying AR Parrot Drones are fun. Put them together and there is pure joy. Ever since I found out that you could program and control your drone over UDP, I couldn’t wait to try it out in Clojure. I had dreams of controlling it with my Emacs REPL. That dream came true and it has been a true joy to fly in a function language. This blog post shows some of the features that the clj-drone project has so far. There is still a bit of work to go to make it complete. But, I wanted to share and hopefully encourage others to start playing with it too. ...