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Showing posts from March, 2016

How to Make a robot 7

Lesson 7 – Using Sensors Unlike humans, robots are not limited to just sight, sound, touch, smell and taste. Robots use a variety of different electromechanical sensors to explore and understand their environment and themselves. Emulating a living creature’s senses is currently very difficult, so researchers and developers have resorted to alternatives to biological senses. What can humans sense that robots can’t? Robots can “see” but have a hard time understanding what they are looking at. Using a camera, a robot may be able to pick up an image made up of millions of pixels but without significant programming, it would not know what any of those pixels meant. Distance sensors would indicate the distance to an object, but would not stop a robot from bumping into it. Researchers and companies are experimenting with a variety of different approaches to permit a robot to not only “see” but “understand” what it is looking at. It may be a long time before a robot is able to differe

How to Make a Robot 6

Lesson 6 – Controlling your Robot The definition we have chosen for a “robot” requires the device to obtain data about its environment, make a decision, and then take action accordingly. This does not exclude the option of a robot being semi-autonomous (having aspects which are controlled by a human and others which it does on its own). A good example of this is a sophisticated underwater robot; a human controls the basic movements of the robot while an on-board processor measures and reacts to underwater currents in order to keep the robot in the same position without drifting. A camera onboard the robot sends video back to the human while onboard sensors may track the water temperature, pressure and more. If the robot loses communication with the surface, an autonomous program may kick-in causing it to surface. If you want to be able to send and/or receive commands from your robot, you will need to determine its level of autonomy and if you want it to be tethered, wireless or ful

How to Make a Robot 5

Lesson 5 – Choosing a Motor Controller What is a motor controller and why do I need it? A motor controller is an electronic device (usually comes in the shape of a bare circuit board without enclosure) that acts as an intermediate device between a microcontroller, a power supply or batteries, and the motors. Although the microcontroller (the robot’s brain) decides the speed and direction of the motors, it cannot drive them directly because of its very limited power (current and voltage) output. The motor controller, on the other hand, can provide the current at the required voltage but cannot decide how fast the motor should turn. Thus, the microcontroller and the motor controller have to work together in order to make the motors move appropriately. Usually, the microcontroller can instruct the motor controller on how to power the motors via a standard and simple communication method such as  UART  (a.k.a. serial) or  PWM . Also, some motor controllers can be manually cont