SENSITIVE SKIN DESIGNING AN ALL-SENSITIVE ROBOT ARM MANIPULATOR in .NET

Generation PDF-417 2d barcode in .NET SENSITIVE SKIN DESIGNING AN ALL-SENSITIVE ROBOT ARM MANIPULATOR
SENSITIVE SKIN DESIGNING AN ALL-SENSITIVE ROBOT ARM MANIPULATOR
Scan PDF 417 In .NET Framework
Using Barcode Control SDK for .NET framework Control to generate, create, read, scan barcode image in VS .NET applications.
collision. How close is close enough depends on a number of variables, such as the robot mass, velocity, and the agility of the robot sensors. The term contact will thus cover a range of distances from a physical contact (a zero distance) to distant sensing, and it can therefore include tactile as well as various proximal sensors infrared, ultrasound, capacitance, vision, and so on. Infrared sensing has been used in the system described in Sections 8.3 and 8.4. The full coverage requirement makes one think of a sensing hardware that would be akin to a sensitive skin, enveloping the whole robot body the way a human skin envelops our bodies. Technically, this may be a real skin or a virtual skin that is, a set of sensors that together provide information about the space around the robot s whole body. Besides the full coverage and locality identi cation properties of robot sensing, the designer of a sensitive skin system has to worry about its other characteristics, such as these:
PDF-417 2d Barcode Encoder In .NET Framework
Using Barcode generator for .NET framework Control to generate, create PDF-417 2d barcode image in VS .NET applications.
Reliability Accuracy Resolution Tactile or proximal sensing Ability to measure distances Physical principle of action: force, vision, infrared, capacitance, ultrasound, etc Sensors physical shape and dimensions Control electronics
PDF-417 2d Barcode Scanner In Visual Studio .NET
Using Barcode scanner for VS .NET Control to read, scan read, scan image in Visual Studio .NET applications.
In the following sections we will consider details and implications of these characteristics for the robot-sensitive skin system, followed by a brief description of one such system developed and installed on a large arm manipulator, along with examples of its operation.
Barcode Generation In Visual Studio .NET
Using Barcode drawer for Visual Studio .NET Control to generate, create bar code image in VS .NET applications.
8.2 SALIENT CHARACTERISTICS OF A SENSITIVE SKIN
Recognizing Bar Code In Visual Studio .NET
Using Barcode reader for Visual Studio .NET Control to read, scan read, scan image in VS .NET applications.
Reliability. Robot sensors must be reliable: We do not want our robot to bump into an object that its sensors did not notice. To provide the full coverage, many sensors will likely be needed, thousands or even millions of them. (Later we will address the question, Why is having many sensors on the skin better than having fewer sensors, even if fewer sensors could do the coverage ) Each sensor is a single device. The common wisdom says that the more devices, the bigger the chance that some of them will misbehave or die. Notice that the latter does not necessarily mean worse reliability. If sensors on the skin do their work in parallel, and if more than one sensor can functionally cover every point of the robot body (thus providing a system redundancy), then more misbehaving elements does not necessarily mean a less reliable system.
PDF 417 Drawer In Visual C#
Using Barcode creation for VS .NET Control to generate, create PDF-417 2d barcode image in .NET framework applications.
SALIENT CHARACTERISTICS OF A SENSITIVE SKIN
PDF-417 2d Barcode Drawer In .NET
Using Barcode generator for ASP.NET Control to generate, create PDF417 image in ASP.NET applications.
The system will be more reliable if it is capable of self-diagnostics, selfhealing, and graceful degradation. Self-diagnostics is a well-developed discipline in system design. Our system would continuously poll all its sensors and inform the control unit of detected deviations from the normal. Self-healing implies an automatic repair of the failed hardware. On the level of sensors today, this feature is available in live nature but not in technology. The purpose of graceful degradation property is to avoid the need to shut off the whole system in case of losing a few elements. In our case, graceful degradation refers to the system s capacity to direct sensors in the vicinity of a broken sensor to take over its job (see, e.g., Ref. 140). Doing this will effectively increase the distance between well-functioning sensors; while slightly degraded, the system will still function. As more sensors die, the system will degrade gracefully.
Printing PDF-417 2d Barcode In VB.NET
Using Barcode drawer for VS .NET Control to generate, create PDF417 image in .NET framework applications.
Accuracy. Sensing information has to be accurate. Sensor accuracy is de ned by the difference between the sensor measurement and the actual value that the sensor attempts to measure. How accurate is accurate enough The answer depends on many details, including the sensor types and density on the skin, and on the robot s mass, kinematics, and maximum speed. Imagine that our robot arm manipulator is equipped with short-range proximity sensors capable of detecting an object when the distance to it from the robot falls below 20 cm. The arm is a heavy body made of steel; its inertia is high. Imagine that at its maximum speed the robot control system can guarantee a successful collision-avoiding maneuver only if the distance to an object on the robot s way at the time of detection is no less than 15 cm. This means that we would not be happy with a sensor whose accuracy is 5 cm, because with it we would run a risk of the arm colliding with surrounding objects. Resolution. This characteristic refers to precision with which the robot can pinpoint the location of an object that appears in the vicinity of the robot body. The better the robot knows the location of an object that it tries to avoid, the better the dexterity of its motion and, hence, its chance to accomplish its task in a workspace lled with obstacles. Sensor resolution is tied to the sensor accuracy, but it characterizes the whole sensor system rather than a single sensor. As an example, consider a sensitive skin that is based on proximity infrared sensing. Unlike passive sensors like a vision camera or a temperature sensor, an infrared sensor is an active sensor: It contains (a) a light-emitting diode (LED) that sends a ray of infrared light in space and (b) a detector that sits right next to the LED and detects the light s re ection from an object in front of the sensor. For better resolution we are interested in a sensor that would send light in a narrow cone. Such sensors, each with a tiny lens in front of the LED in order to produce a cone-like light ray, are common (see Figure 8.2a). They may have a limited sensitivity distance, say 20 or 30 cm. For full coverage, sensors are spaced on the skin so that their sensitivity cones overlap, forming a continuous sensitivity cushion around the robot. The fact of detecting a re ected signal thus means that the object in question is wholly or partially within the sensitivity cone and sensitivity distance of a given sensor.
Make Code 39 In VS .NET
Using Barcode creator for .NET Control to generate, create Code-39 image in .NET framework applications.
Painting EAN13 In .NET
Using Barcode creation for .NET Control to generate, create EAN-13 image in .NET framework applications.
Code 11 Creator In .NET
Using Barcode encoder for VS .NET Control to generate, create USD - 8 image in .NET framework applications.
ECC200 Encoder In VB.NET
Using Barcode creation for Visual Studio .NET Control to generate, create Data Matrix ECC200 image in .NET applications.
Recognize Bar Code In Java
Using Barcode recognizer for Java Control to read, scan read, scan image in Java applications.
Make UCC - 12 In Visual C#
Using Barcode creation for .NET framework Control to generate, create UPC A image in VS .NET applications.
Code 39 Encoder In .NET Framework
Using Barcode creation for ASP.NET Control to generate, create Code 39 Full ASCII image in ASP.NET applications.