Basic Servo Gripper

I was going through some pictures of projects I undertook whilst at University, I came across some pictures of a servo driven robotic gripper that was made for the Mechatronics 2 course.


The gripper uses one servo to open and close the jaws, the servo horn was mounted onto a plastic gear. This gear was a modified from a Meccano set this proved be much easier than fabricating a gear system to suit. The gripper uses a double arm system in order to keep the jaws some-what parallel. It was deliberately made so they weren’t perfectly parallel as the primary objects to be grasped were cylinders.

The gripper used 1.6mm Aluminium sheet, M3 Bolts, Metal Washers, Nylon Spacers and Nylon nuts. The plastic Meccano gears are bolted onto the servo using M2 Bolts.

The gripper had an opening of about 100mm and could hold an object slightly small than the film canister shown above (<30mm OD). The servo draws a maximum of about 300mA when changing positions and when the correct locations are chosen for holding an object the idle current is around 30mA. This current can be a lot more if the object needs to gripped tight (i.e. grasping a heavier object).


If I were to rebuild this, I would make the following modifications:

  • New base plate – To allow a lift servo to be attached.
  • Better mounting bracket
  • Rubberized Foam Finger Grips – To help stop objects slipping out.
  • Standalone Servo Controller.