Design, modeling and control

This is a project in cooperation with Dr. ir. D. Brouwer.

Manipulators with guidance constructions based on elastic mechanisms are of interest for the increasing number of precision vacuum applications. Previously, the design of an elastic MEMS-based 6-DOFs manipulator was presented. Characterization in six degrees of freedom (DOFs) of a manipulator the size of several square millimeters, however, is difficult. Therefore, a scaled-up version of the manipulator was built. This ‘macro’ version serves as a research platform for the verification of the flexible multibody model including control that was set up using the SPACAR toolbox for Matlab.

6 DOFs motion of the manipulator: http://www.youtube.com/watch?v=q80ypiG-HDg

Modes by SPACAR of the scaled-up manipulator: http://www.youtube.com/watch?v=pK22CxDQ0gU

Figure 1. Scaled-up set-up with clamped points indicated by dashed circles

Figure 2. The 4 compliant DOFs and 2 actuated DOFs of the end-effector by one slanted leaf-spring connection.

Figure 3. Two actuated DOFs per slanted leaf-spring results in six actuated DOFs of the end-effector.

Figure 4. The actuator with guidance.

Figure 5. SPACAR model.

Figure 6. Transfers between actuator force and displacement as obtained by SPACAR.

Figure 7. Experimentally determined frequency responses.

Figure 8. Experimental set-up.

Mode

Model (rad/s)

Exp. (rad/s)

Error (%)

1

54.6

55.8

2.2

2

55.2

57.0

3.3

3

81.1

80.2

1.1

4

83.3

85.2

2.3

5

119

118

1.2

6

122

-

-

7

624

589

5.9

8

787

753

4.5

9

836

800

4.5

Table 1. Experimentally determined eigenfrequencies with the relative error

For more information:

M.B.P. Huijts, D.M. Brouwer, J. van Dijk, Scale-up for model verification; Design, Modeling and control of an elastic parallel kinematic 6-DOFs manipulator, Mikroniek 5, 2009, pp42-47, ISSN0026-3699.

M.B.P. Huijts, D.M. Brouwer and J. van Dijk, Design and Control of a Parallel Kinematic 6-DOFs Precision Manipulator, Proc. of the EUSPEN Int. conf., San Sebastian, Spain, 2-5 June 2009, Vol.I, pp.357-360, ISBN 0-9553082-6-0.