الفهرس 
Chapter One : Introduction and Literature SurveyOnly 14 pages are availabe for public view
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Abstract
Safe transportation and carriage of items is a frequent industrial implementation that is heavily employed in production lines, particularly by grippers, hence it is quite important to determine coefficient of friction (COF) and electrostatic charge (ESC) to confirm safe holding. The use of ESC and friction to control COF may be beneficial since a gripping force might be too strong, causing the object to be destroyed, or it might be too tiny, forcing items to slip.
Present work investigates the COF and the electrostatic charge under the effect of an electric field between gripper surfaces and objects. Specimens from rubber with different surface roughness and hardness were experimentally tested as a cover surface for the gripper. The tested objects were polyester textiles, papers and surface of some vegetables. The rubber was rubbed against polyester textile surfaces. As results, when the applied (normal) load increased, COF decreased and it increased significantly with increasing the hardness of rubber surface. There is a significant increasing in the COF up to maximum value then because the surface roughness increased then it slightly decreased. This observation advises more check to select and choose the proper type of rubber as a covering material for gripper.
The ESC value was higher in the existence of electric field than that was remarkable with the absence of electric field. Increasing the ESC due to existence of electric field which give rise to an increase in adhesion force among the contact surfaces leading to friction increasing. The friction of rubbing surfaces cause defects that enforce the trapped charges to make an effect on those defects so, the ESC appears an important role in influence friction and adhesion. The high voltage is expected to provide the slipping surfaces with extra or more ESC. Depending on the previous observations, the friction increases as result of adhesion increasing between slipping surfaces.