IT 435 Digital Instrumentation and Controls

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IT 435 Digital Instrumentation and Controls

• Week 9
• Robots (Chapter 18) and PC control

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Control using a PC
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Robots

• Mechanical device programmed to perform a
  manipulative task under automatic control
• Easily reprogrammed
• Good for repetitive processes
• Effective in hazardous areas

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List and describe the five major types of robots

• Cylindrical
• Three axes of motion - vertical, rotary, extend

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Types of robots

• Rectilinear or Cartesian
• x, y, and z

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Types of robots

• Both rectilinear and cylindrical
• Typically rotate to a stop
• ON - OFF implementation (Bang Bang)
• Pneumatic or electrical motor drive
• Wrist actuation not usually considered part of
  the robot function
• Considered manipulator motion (roll)

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Types of robots

• Spherical
• Rotation, angle, and extension
• Usually PLC controlled
• Often trainable using a control or teach pendant

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Types of robots

• Jointed spherical
• Jointed arm
• Rotation, angle, extension, and joint
• Anthropomorphic articulated (human-like)
• Able to reach hard to get at places
• Painting, welding
• Complex controls

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Types of robots

• Selective compliance assembly robot arm (SCARA)
• Cylindrical with versatile arm

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Extending robot motion

• Tracks
• Tape, buried electrical cable, GPS
• AGVs

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List four types of end effectors

• Welding electrodes
• Vacuum cups
• Mechanical gripper
• Glue applicator
• Grinding wheel
• Polisher
• Paint nozzle

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Effectors
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Describe the role of vision systems with robots

• Vision is dream (goal) of robots
• Stereo-graphy difficult
• Pattern recognition
• Generally bit comparison
• Real problem with edges, orientation
• Obstacle avoidance

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Define work cell

• Several machines working together
• Often, one or more robots also
• Work cell often PLC controlled