Robotics Capstone

Card Set Information

Robotics Capstone
2013-03-05 22:37:38

Homework 4-5-6
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  1. 1) Describe five application areas for vision systems.
    • 1. Part identification
    • 2.  Part location
    • 3. Part orientation
    • 4. Part inspection
    • 5. Range finding
  2. 2) What are the basic components of a vision system?
    One or more cameras, a camera controller, interface circuits and systems for the camera and work-cell equipment, a high-resolution cathode ray tube (CRT) for image display, and a lighting system for the parts.
  3. 3) What 2 types of cameras are currently used?
    • Charge-coupled device (CCD) camera.
    • Vidicon tube camera.
  4. 5) describe edge detection and clustering.
    • Edge detection is based on the fact that there is a sharp difference in brightness between the object and its background areas of high contrast are found by searching through the array of pixel data for jumps in the gray level to locate the change in gray level, a mathematical operator examines a small neighborhood of adjacent pixels and computes an edge probability value. If the value is above a set threshold, then a notation is stored in the vision controller memory and part data indicating a probable part edge.
    • Clustering or region growing, this technique uses a discrimination function to determine if a pixel is a part of a region being developed. The discrimination function computes the desired properties of a pixel and compares them with the properties of other pixels in the region or against a threshold value.
  5. 6) Describe the 3 commonly used techniques for 2D recognition with vision systems.
    • Template matching: templates of the parts to be recognized are stored in the vision system memory. The images recorded by the vision camera are compared with the templates.
    • Edge and region statistics: this technique defines significant features for the parts studied, the develops a method of evaluating these features from the pixel data.
    • Statistical matching: the statistical data for parts to be identified are stored in memory, and when the camera produces an image of an unknown part, the system calculates a set of feature values from the pixel data, and the compare them statistically with the ones stored in memory.
  6. 11) What are the 2 basic functions of material handling?
    • 1. Move the part in the most appropriate manner between production machines.
    • 2. Orient and position the part with sufficient accuracy at the machine to maximize productivity and maintain quality standards
  7. 12) Describe the 3 basic types of material-handling systems.
    • Continues transfer: the par moves through the production sequence at constant speed.
    • Intermittent transfer: workstations fixed in one place and movement of the part is discontinuous.
    • Asynchronous transfer: each part moves independently of other parts.
  8. 15) Describe the 3 techniques most frequently used for automatic tracking of production parts and material.
    • 1. Bar code: a symbol composed of spaced parallel bars with varying width that represent a series of alphanumerical characters.
    • 2. Radio frequency tag: passive electronic circuits that transmit a code when subjected to radio frequency energy. The tracking device receives the tool code and records the number.
    • 3. Binary code: the pallets have a sequence of holes, some holes are filled with pins. when the pallet passes under the sensor or switches, the holes with pins trip the sensor or switch.
  9. 1.) What is the basic function of sensors in an automated work cell both with and without a robot present? 
    The basic function of sensors in an automated work cell is to detect condition where an operator or any human being can be harmed by the robot  , and to monitor production parts to determine current level of quality, quantity, and to ensure system parameters are in correct setting. 
  10. 3.) What are the two categories into which all sensors can be grouped?
    All sensors can be grouped into two categorizes called contact and noncontact.
  11. 5.) What is the definition of a limit switch? 
    A limit switch is a discrete device contact switch actuated when the motion of a part moves an operator on the switch. 
  12. 6.) What are the four basic parts of every limit switch? 
           It is a mechanically actuated electrical switch consisting of a receptacle, switch box, operating head, and lever contacting device. 
  13. 9.) What is the function of the lamp in a limit switch? 
    The function of the lamp in the limit switch is to indicate on what pole it’s operating in
  14. 13.) What sensors are included in the non contact sensor group?
    Sensors included in the non contact group are proximity and photoelectric device sensors. 
  15. 16.) What three output circuits are available on proximity sensors?
    The three outputs available in a proximity sensor are two wire or three wire outputs. The three wire output consists of NPN or PNP transistors. 
  16. 1.- What is end-of-arm tooling and what  function does it serve?
    • 1. The tooling must be capable of gripping, lifting, and releasing the part or family of parts required by the manufacturing process.
    • 2. The tooling must sense the presence of a part in the gripper, using sensors located either on the tooling or at the fixed position in the work cell.
    • 3. Tooling weight must be kept to a minimum because it is added to part weight to determine maximum payload.
    • 4. Containment of the part in the gripper must be ensured under conditions of maximum acceleration at the tool plate and loose of gripper power.
    • 5. The simplest gripper that meets the first four criteria should be the one implemented.
  17. 11.- Describe the three compliance conditions normally found in robot applications.
    • Compliance means initiated or allowed part movement for the purpose of alignment between mating parts.
    • 1) Active Compliance 2) Passive Compliance 3)Selective Compliance