Object detection system
AssigneeBPM Microsystems
InventorsWilliam H. White, Alain Mangiat, Rudy DeLeon
Life of this patent
Estimating the term…
Abstract
An object detection system utilizes a teach cycle performed with a low-pressure blow-off (i.e. positive pressure) instead of vacuum (negative pressure). During the teach operation, the positive pressure is enabled and the nozzle is lowered to the object. An air sensor detects pressure or flow at the nozzle tip. A rise in pressure or drop in flow is detected as the nozzle makes contact with the object (i.e. just before or just after actual physical contact is made). The height of the object is stored as the taught height to be used subsequently in repetitive operations by the machine. This teaching method is particularly useful for very small objects because the positive pressure does not lift the object.
Claims20
A pick and place system comprising:
- a nozzle configured to supply positive pressure and positive flow, the nozzle movable toward an object;
- a sensor configured to detect at least one of the flow or the pressure of the nozzle while the nozzle is supplying positive pressure and positive flow;
- and
- a processor configured to receive an indication from the sensor of the at least one of the flow or the pressure of the nozzle and configured to control movement of the nozzle toward and away from the object, the processor configured to determine a threshold based only upon a maximum steady state flow and a minimum steady state flow of the nozzle or based only upon a maximum steady state pressure and a minimum steady state pressure of the nozzle, the processor configured to determine the location of the object based upon a change in the at least one of the flow or the pressure of the nozzle relative to the threshold while the nozzle is supplying positive pressure and positive flow.
A pick and place system comprising:
- a nozzle configured to supply positive air flow and negative air flow;
- a displacement device configured to move the nozzle toward an object;
- a sensor configured to measure at least one of air flow or air pressure of the nozzle;
- and
- a processor configured to receive an indication from the sensor of the at least one of the flow or the pressure of the nozzle and configured to control the displacement device to move the nozzle toward the object, the processor configured to determine a threshold based upon a difference between a maximum steady state flow and a minimum steady state flow of the nozzle or based upon a difference between a maximum steady state pressure and a minimum steady state pressure of the nozzle, the processor configured to determine the location of the object based upon a change in the at least one of the air flow or the air pressure of the nozzle relative to the threshold while the nozzle is supplying positive pressure and positive flow.
A method for calibrating a pick and place system including the steps of:
- a) moving a nozzle toward an object;
- b) supplying fluid out of the nozzle toward the object;
- c) during said step b), determining a threshold based upon a difference between a maximum steady state pressure and a minimum steady state pressure or based upon a difference between a maximum steady state flow and a minimum steady state flow of the fluid supply;
- d) detecting a change in the fluid supply as the nozzle contacts the object based upon a comparison of the pressure or flow of the fluid supply to the threshold;
- and
- e) storing the location of the nozzle based upon said step d).
Dependencies are inferred from the claim text.