Design Concepts and Control of Automatic Systems

Since ancient times man has imagined automated mechanisms or intelligent devices to take over various activities or parts of his work, in the timeless quest to make life easier, more comfortable and achieve goals not possible otherwise. Automatic control systems (ACS) have a very long history, it is arguably considered that the first such system appeared around the third century B.C. in the form of Ktesibios’s water clock and numerous other examples of such automatic devices being recorded throughout history in different periods of time.

The concept of robot is somewhat younger, only 500 years old and can be traced back to the days of Leonardo da Vinci, his work containing numerous depictions of automated mechanisms or even robotic structures. The actual term surfaced in 1920, when Czech writer Karel Capek published the play R.U.R., short for Rossum’s Universal Robots.

Ktesibios’ water clock | Photo: Swansea University

Etymology of the word robot has Slavic origins, with meanings equivalent to work or chore in the Russian and Czech language respectively. American science-fiction author Isaac Asimov made the term more mainstream and also foresaw the electronic brain that controls a robot. He also devised the Three Laws of Robtics. Continue reading (…)

Self Driving Cars are Just Robots with Four Wheels

Looking for a new address where you want to travel on a huge touchscreen with internet connection, sit more comfortably in the seat that can be adjusted in infinite positions and press the start button – a futuristic scenario which regarded through the lens of new technologies in prototyping stage will become reality in the coming years. BMW, Audi, DARPA or Google are only four big names who invest time and money in new intelligent cars, autonomous vehicles – intelligent robots with four wheels. In the following years electric cars technologies will be improved and will open a wide door for a new generation of cars without drivers. Electric power is preferred by most entities who invest time and money to develop intelligent machines, something that can be understood as the future belongs to them. Bits used to control the car will take care of the passengers to reach their destination safely and in the shortest time. The reduction or even elimination of any car driving mistakes will have a positive effect on the number of accidents which in turn will be reduced or will be removed. To build a self driving car engineers use a long list of sensors and software including GPS, laser technology, or operating systems that can control the flow of information and parallel processes running.

Road authorities from different European countries or the North American continent have taken notice of these new intelligent cars and allowed the testing of models on the streets with heavy traffic. In this article we try to expose most projects aimed to build self driving cars, projects belonging to famous companies from the automotive industry or some giant companies with completely different fields of activity than robots but who have vision and will become part of the future.

Google

Google car is perhaps the most advanced self driving car, a technological advance in automotive that has drawn praise and a large number of articles in print or online. The Google car is a prototype from the future and comes to ransack people’s imagination who have the opportunity to watch it in action on the streets of U.S.

Google Lexus Self Driving Car

The tests were started on a Toyota Prius, but Google has moved the technology into a slightly larger car – Lexus RX450h hybrid. The car has driven so far a record number of 300,000 miles. Even if at some point the Google car (at that time a Toyota Prius) went through an accident, a human error was the primary cause and not the robot car. This case confirms once again that humans can cause errors even surrounded by advanced technology. Continue reading (…)

Walkthrough on Controlling a Stepper Motor

In our article about stepper motors we have presented this type of electric motors, how they operate and what makes them highly compatible with digital control systems. Now we will talk about how to control such a motor together with a simple example, involving a H-bridge electronic circuit and simple scripting. In our implementation we have used a bipolar stepper motor, however minor changes in control sequences are required for other types of stepper motors.

Stepper Motor attached to LEGO build

Stepper Motor attached to LEGO build

To summarize, the electromagnetic coils are located on the stator of the stepper motor, while permanent magnets, equal in pair numbers, are located on the rotor. A more detailed discussion about stepper motors can be found in our dedicated article, but making a long story short, like any DC motor, these motors rotate when the coils are energized however, if the coils are continuously energized in the same way, the movement will stop when opposite magnetic poles are aligned, e.g. S-pole on coil aligned with N-pole on rotor permanent magnet.

Continue reading (…)

Motor Drive Shields – Arduino Compatible

Robot parts movement is produced by actuators which are usually electric motors. These electric motors need power to work, which needs to be delivered steadily and controllable. A motor driver is an electronic module which is essentially an interface between electronic control units and final effectors, in our case electric motors. This electronic circuit is designed to send the required amount of energy and to control the electric motor, particularly important since power requirements can vary to a great extent between control electronics and actuators.

Using a motor drive shield together with an Arduino controller board is the perfect recipe for rapid robot development and precise control. Moreover by employing such circuit two or more DC motors, servos or even steppers can be controlled, which is usually a necessity given the increasing complexity of robots.

Continue reading (…)

Telepresence Robots Reviewed – Part 2

We now continue our telepresence robot review, presenting to you more interesting robots and applications in the market, although some of them are yet to be released. You can read the first part of our roundup here or skip to part 3 directly.

Anybots QB Robot

The Anybots QB robot is a two wheeled self balancing robot that can be controlled through a simple web interface. It is primarily aimed at office environments, designed to enable the remote user to go to conference rooms, join conversations, roam around the office building and so forth.

Continue reading (…)

Concurrent Programming and Intelligent Robots

A complex robot is backed up by busy intersections with commands and information that require processing. Simultaneous control of several actions require several processes that work in parallel and are sustained by high computing power. The difference between a robot that is moving in an environment with obstacles and a robot which makes a sound out when the light is on is enormous in terms of computation and processes that take place simultaneously, if the robot that detects the light uses a light sensor to send information, an autonomous robot that is moving and avoids obstacles uses a range of sensors to collect information about the environment.

The program used to control actions of a robot has an essential role. There is a sequential program type that performs a particular action at a time, and concurrent programs that receive informations in the same time from multiple sensors and sustain continuous activity of the system even in the case when sensor delay in sending information becomes significant or it simply does not work. In this article we try to describe in simple and comprehensive terms concurrent programming to build complex robots.

Intelligent Robots

What is concurrent programming

Concurrent programming rises up to the most difficult level in the programming process and generally addresses programmers with an above average level in programming and with some experience in the field. The emergence of these programming techniques was imposed due to the need to run several streams of operations in a concurrent way. Continue reading (…)

Infrared Sensors List Used in Robotic Projects

Robots can employ many types of sensors with very different operating principles and features to acquire data from the environment. In this article we focus on reviewing sensors which operate by detecting infrared radiation in one form or another. Infrared sensors for robots are used for a variety of purposes, there are IR range sensors used for measuring distances to objects, IR proximity sensors which can successfully replace physical contact sensors, passive infrared (PIR) sensors which can be used to detect motion based on detecting heat radiated by a body, IR sensors used for data transmission — either between robots or with a stationary beacon or base — and positioning, and even gas concentration measurements can be performed with certain types of IR sensors.

Sharp GP2Y0A02YK0F IR Range Sensor

GP2Y0A02YK0F is an infrared sensor build by Sharp and is one of the most powerful infrared sensors that can be used to build a robot.

Sharp GP2Y0A02YK0F

Sharp GP2Y0A02YK0F

Sharp GP2Y0A02YK0F is a distance sensor composed of three elements:

  • Position sensitive detector;
  • IRED (infrared emitting diode);
  • Signal processing circuit.

Continue reading (…)