Sunday, November 30, 2008

Robotic Gripper 2

pneumatic gripper

A gripper was designed for transplanting. The gripper seedlings
grasping is composed of a pneumatic piston which actuates
two parallel hinged jaws that perform a scissors type movement,
which cause the jaws to grasp the plant in between. The size
and shape of the gripper was adapted to fit trays with different
plant cells sizes.

slider gripper

This is the first of six soft tissue grippers. The gripper, thanks to two
suction cups, can pick and place large portions of fabric.
The distance between the two suction cups can be adjusted to
better fit the fabric size.

The 3-Jaw Parallel Gripper

The 3-Jaw Parallel Gripper is ideal for applications requiring three
points of contact, positive pick and place, and the flexibility of stroke.
It offers self-centering of parts and a high clamping force for
rapid part transfer and part gripping during grinding or de-burring, etc

Sunday, November 23, 2008

Robotic Gripper 1

A parallel jaw gripper

A parallel jaw gripper A parallel jaw gripper was developed for the
robotic arm for pick and place operations. To maintain the jaws
of the gripper parallel to each other, they were connected through
a parallel mechanism of links. A linear actuator actuates the gripper.
A CAD model of the gripper mechanism is shown on the
right. The mechanism simulation was done in Idea8 mechanism

Robotic Gripper Sizing

The force that a robotic gripper applies to a part is typically used by
engineers to select grippers. While gripper force is a first order
consideration, the torque that is experienced by the gripper is equally
as critical and, unfortunately, usually only addressed in a cursory
manner. In some cases the torque is addressed via the gripper
manufacturer supplying jaw length vs. force charts. These gripper
charts are helpful but are only useful in low G-force applications
and provide rough guidance at best. The result of this situation is
that “rookie” gripper application engineers end up with dropped
parts and “old hands” end up with grippers far larger and more
expensive than required. Before we start let's look at some of the
lore that is wrong!

Rotational gripper

The 1 DoF gripper is the end effector of a parallel robot for
high speed assembly tasks. The gripper is mounted on a triangular
plate. The parallel architecture of the robot drives the plate
translation. An actuator rotates the whole robot (instead of the
plate itself) to allow the gripper rotation around an axis normal
to the plate; this solution minimizes the inertia of the end-effector.

Robotic Gripper Index

Robotic Gripper