Advantages & Disadvantages of each robot

1. Robot arm
Configurations
14BME133D - PARTH DASADIYA

2. Robot Configurations
 Robot manipulators are available in several different styles/configurations.
This page shows five industrial robot configurations and their respective
work envelopes. Several videos are included showing the robot
configurations in-use.

3. Spherical
 The first industrial robot, the Unimate, was a spherical robot. Sperical
robots are rarely (if ever) used today.
Advantages
 Large workplace for size
 Easily computed kinematics
Disadvantages
 Has shot vertical reach
 Horizontal axis frequently in the
way
 Also fallen” out of favor” and not
common in new design

4. Cylindrical
 It uses a vertical column and a slide that can be moved up or down along
the column.
 The robot arm is attached to the slide so that it can be moved radially
with respect to the column.
 By rotating the column, the robot is capable of achieving a work space
that approximates a cylinder.
 It contains two linear motions and one rotational motion.
 Angular Motion, θ along vertical axis; Translation Motion, z along
 z-direction that corresponds to up and down motion; Radial, r in or out
translation.

5. Cylindrical
Advantages
 Large workspace for size
 Easily computed kinematics
 Can reach all around itself
 Reach and height axes rigid
Disadvantages
 Cannot reach above itself
 Horizontal axis frequently in the
way
 Largely fallen “out of favor” and not
common in new design.

6. Cartesian or Linear
 Cartesian robots are perhaps the easiest and least expensive robots to build. They can be
made using linear actuators (electric or pneumatic) and programmed using a PLC or PC.
The axis configuration of Cartesian robots provides good rigidity compared with other
robots configurations.

7. Cartesian or Linear
Disadvantages
 Not space efficient
 External frame can be massive
 Z axis “post” frequently in the way
 Axes hard to seal
 Can only reach in front of itself
Advantages
 Easy to visualize
 Have better inherent accuracy
than most other types
 Easy to program offline

8. SCARA
 Notation VRO
 SCARA stands for Selectively
 Compliant Assembly Robot Arm
 Similar to jointed-arm robot except that
vertical axes are used for shoulder and
elbow joints to be compliant in horizontal
direction for vertical insertion tasks

9. SCARA
Advantages
 Fast cycle time
 Excellent repeatability good
payload capacity
 Large workplace
 Height axis is rigid
Disadvantages
 Hard to program off-line
 Often limited to planar surfaces
 Typically small with relatively low
load capacity
 Two ways to reach same point.

10. Articulated
 A robot with at least 3 rotary joints.
Commonly used for:
 assembly operations
 welding
 weld sealing
 spray painting
 handling at die casting or
 fettling machines

11. Articulated
Advantages
 all rotary joints allows for
maximum flexibility
 any point in total volume can be
reached.
 all joints can be sealed from the
environment.
Disadvantages
 extremely difficult to visualize,
control, and program.
 restricted volume coverage.
 low accuracy