It’s now our tradition to issue virtual machines with ROS pre-installed. We have already done it for ROS Fuerte and for ROS Groovy. Today it is ROS Hydro’s turn. We have chosen to stick with Ubunutu 12.04. (Precise). This is because 12.04 is an LTS version, which means Long-Term Support. The Ubuntu community will be maintaining it for 5 years. The ROS Hydro virtual machine comes in a single file .ova of approx. 3.7GB. You can launch it using VirtualBox, ...
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• Part 1: Mechanical Design Basics.
• Part 2: Balancing the Elevator.
• Part 3: Electronics (optocoupler, H-Bridge, and more).
• Part 4 (current): Software to control the Arduino.

In this last part, we will be describing the Arduino software that controls our Lego elevator. But, let’s first define the desired behavior. As we have described in the part dedicated to the electronics, our circuit provides two push-buttons. One is supposed to make the elevator go up, and the other is for ...
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One of the challenges that thinkers have been facing for decades is defining intelligence. Without such a definition, it’s hard to measure intelligence or to make truly intelligent robots. In his TED talk (see Video below), Alex Wissner-Gross introduces an equation that is supposed to provide a concrete, yet general answer. Wissner-Gross defines intelligence as the ability to maximize future options. This is related to the concept of entropy well known in physics. Indeed, entropy is a measure of the ...
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• Part 1: Mechanical Design Basics.
• Part 2: Balancing the Elevator.
• Part 3 (current): Electronics (optocoupler, H-Bridge, and more).
• Part 4: Software to control the Arduino.

In the first two parts of this series, we have introduced the mechanics of our Lego-based elevator and we discussed how to balance it to lift some load. Today, we will be discussing the connection between the Lego Mindstorms' motor and touch sensors with an Arduino board. Lego Components Characteristics First things first, ...
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Wanna learn how to make mobile robots? This free online course entitled “Control of Mobile Robots” is for you (see Video 1). The tutor is Dr. Magnus Egerstedt, a Professor in Georgia Tech’s School of Electrical and Computer Engineering. For 7 weeks, he will be introducing concepts from control theory, and how to map them onto an actual physical platform. In addition, an introduction into microcontrollers, mechatronics, and electronics will be given so that, by the end of the course, ...
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Wana play a trick to your friends? Use SkyJack a software that takes over the control software of AR Drones. It analyzes raw Wifi data packets to perform the drone hijacking. The video below by Samy Kamkar gives more details about how it works. The code is freely downloadable from GitHub. Hope that Amazon and UPS will take this as a serious warning and address security issues before launching commercial drone applications. ...
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• Part 1: Mechanical Design Basics.
• Part 2 (current): Balancing the Elevator.
• Part 3: Electronics (optocoupler, H-Bridge, and more).
• Part 4: Software to control the Arduino.

In the first part of this series, we introduced the core structure of our elevator. But, we aren’t done yet with the mechanics. As shown in Video 1, our initial design was unbalanced. It isn’t usable at all to lift any weight, such as a smartphone. The solution is to lower and move ...
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• Part 1 (current): Mechanical Design Basics.
• Part 2: Balancing the Elevator.
• Part 3: Electronics (optocoupler, H-Bridge, and more)
• Part 4: Software to control the Arduino

Recently, we scavenged an old Lego Mindstorms 1.5 set. It’s fully functional, but the RCX 1.5 Lego software is obsolete and does not run on recent Operating Systems. Besides, the brick has only few in/out ports: 3 inputs and 3 outputs. So, we decided to forget it and reuse Lego parts with an ...
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It is no scoop that Smartphones are attractive for robotics. They gather in a small case a display, wireless for communication, computing capabilities, and a bunch of sensors. That’s cool! But, you might be using a secondhand device, and you don't know what sensors are available, or you may want to check if any is broken. Besides, some sensors are software-based, and thus may be there or not depending on the Android version you are running. This is why we ...
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In this tutorial, we will be talking about ROS namespaces which allow to combine nodes in ways unplanned by developers. This is actually what all ROS is about: allow building systems by connecting nodes, often developed by third parties according to your needs. This is possible thanks to a flexible node naming system. As usual, we will illustrate presented concepts with concrete examples that you can run on your own machine. As a prerequisite, you only need to be familiar ...
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