Figure1: The Hen, a mobile pick and place robot.
During the design for this kind of pick and place robots, some requirements have to be meet.
The robot must move towards the direction of the object to be picked up. The robot has to search
for an object to be picked up with certainty, and lastly it has to pick the object and place it
accurately at the destination point. Thus, the movement, navigation, recognition of the object,
grasping and holding of the object, and place and release will be the key design issues. To
provide for these requirement microcontroller or microprocessors, servomotors, infrared sensors
and actuators would be used. A good example of a mobile pick and place robot is the Hen which
is a manufactured by Tinkernology. The Hen has three Lego PF motors and a small Lego M and
uses infrared red sensors for navigation (Truszkowsk 167).
The robot is run by a program that is often programmed in a microprocessor or a microcontroller.
Microcontrollers are used in those robots that their program does not need to be changed after
manufacturing, they are, however, cheaper than microprocessors. The mobile, pick and place
algorithm would ensure that the robot follow a line by the help of the infrared sensors, until it hit
a bumper that triggers the bump switch for the robot to stop. The arm of the robot would then
drop to pick up the object using the grippers at its end. When the object is well held the robot