1. Chap 11 – Case Studies

2. 11.6 Space Station Remote Manipulator System (SSRMS)

3. 7 axis manipulator, 7 d.o.f. (redundant)
1st & 2nd axes intersect
6th & 7th axes intersect
3rd, 4th, & 5th axes are parallel

4. The manipulator is classified as being redundant since only six joint axes are necessary to position and orient the end effector arbitrarily in space.
The reverse kinematic position analysis will proceed, however, by having the user specify one of the joint angle parameters in addition to specifying the desired position and orientation of the end effector.

5. In the present analysis, the user must specify 2 in addition to the desired end effector position and orientation.
This strategy offers a distinct advantage in that the parameter 2 has a physical meaning for the operator.
This angle governs the orientation of the longest links of the manipulate or (a34 and a45) with respect to the XY plane through the base of the robot.
The prior specification of 2 will enable the user to take better advantage of the redundancy of the system by being able to position the longest links of the manipulator to move over or around obstacles in the workspace.

7. Make a free choice for the offset S7 and establish a direction for the vector a78 in the last link. (Establish the 7th coordinate system.)

8. Obtain the coordinates of the origin of the 7th coordinate system with respect to ground.
Close the loop. Obtain a81, S8, S1, 8, 81, 1.

9. 11.6.1 Development of an Equivalent 6 Degree of Freedom Manipulator
obtain 12’ , a12’, S1’, and S2’

10. special configuration if 2 equals 0 or 180, 4 axes parallel

12. project vector loop onto S2 (z comp. of set 14)
project vector loop onto x & y axes of set 14, square and add
x & y axes of set 14

13. 11.7 Modified Flight Telerobotic Servicer (FTS) Manipulator System
original FTS design
modified FTS design

14. redundant robot
assume 7 is given

15. redundant robot
assume 7 is given

16. redundant robot
assume 7 is given

17. redundant robot
assume 7 is given
calculate
where

18. redundant robot
assume 7 is given

19. redundant robot
assume 7 is given
1st & 2nd axes intersect
3rd & 4th axes parallel
5th & 6th axes intersect