Pick Head
The pick and place head sits on the end effector of the robot, and is used to pick up components from feeders, trays and cut tape, orient them, and place them down on the board. The pick head may also contain several sensors used by the robot. Two approaches are being developed at this stage, a single and a 4 way head.
Concept 1 - single rotating nozzle head

A single rotating head consists of a shaft onto which the nozzle is connected. This shaft is rotated by a motor in order to orient the part on the nozzle.
Vacuum or air supply is accomplished via two air tight bushings. Rotation of the nozzle is not restricted by a flexible hose.
The motor shall be directly coupled to the shaft, and a shaft encoder. .
There is currently no nozzle spring force implemented in the design. We will test load cell sensors in the mounting bracket of the head in order to sense component pick up and placement. We will also be able to adjust placement force from 100 gram to 500 gram.
Prosimple
low mass
Conplacement speed
Actuators
# | Use | Description |
1 | rotate nozzle | low inertia dc servo motor (eg maxon A-max) |
Sensors
# | Use | Description |
1 | measure angle of nozzle | US Digital EC35 10k cpr quadrature encoder |
Concept 2 - 4 position rotary head
The current concept is to use a 4 position rotary head, with 4 individually rotatable nozzles. This allows the robot to pick up 4 components, then traverse to the board and place them, decreasing the average traversal time per component.



Promuch faster placement of small components
ConComplexity
Cost
More motors, encoders
Higher moving mass, so cost impacts in robot actuators
Actuators
# | Use | Description |
1 | rotate nozzle wheel | Servo |
2 | rotate nozzle | Servo / dc motor |
3 | second nozzle rotation | Servo / dc motor, optional, used to pre-rotate nozzle before reaching camera for parts 90deg away from target orientation |
Sensors
# | Use | Description |
1 | Camera facing nozzle | for orientation sensing of picked parts |
Further references
http://www.cnczone.com/forums/rc_robotics_autonomous_robots/141835-open_source_p_p_revolver.html Original post on CNCZone discussing multiple nozzle heads
http://www.cnczone.com/forums/rc_robotics_autonomous_robots/145909-wikiplacer_project.html Discussion of newer 4 post head