a new approach to difficult object detection
TRANSCRIPT
A New Approach to Difficult Object Detection
q This webinar will be available afterwards at www.designworldonline.com & email
q Q&A at the end of the presentation q Hashtag for this webinar: #DWwebinar
Before We Start
Moderator Presenters
Mike Jermann Design World
Corey Loeffelholz Baumer Ltd.
Christ Markis Baumer Ltd.
A New Approach to Difficult Object Detection
Broad Photoelectric Sensor Categories
• Diffuse Sensors o Background Suppression o Distance Measuring o Contrast o Proximity o Fiber Optics o Baumer SmartReflect ™
• Light Barriers o Through Beams o Retro Reflective o Opposed Fiber Optics o Baumer SmartReflect ™
Light Barrier Sensors
Opposed / Through Beams • LEDs, lasers • Alignment • Aperture • Can operate over long distances • Can use an visible or infrared light
Receiving angle Emitting angle
Active area
Active Area of Through Beam Sensors
Retro-Reflective • Often called “retro” or “reflex” sensors • Can use a laser or LED • Inexpensive • Proxing and skew angle • Reflectors differ in quality • Laser reflectors are different from LED reflectors
Unbroken beam (no target present): Only one defined plane of the light emitted passes through the polarization filter (polarized light) The reflector required for this type of sensor depolarizes & rotates the light Only the part of the non-polarized light reflected - which matches the polarization plane of the second filter in front of the receiver - is accepted. All other planes are blocked. Broken beam (target present): When a shiny target breaks the beam, it reflects the polarized light without changing the plane of polarization. The light is therefore not seen by the receiver (blocked by the differently oriented filter on the receiver)
Polarized Retro Reflective
Note: filters on emitter & receiver are differently oriented!
Reflector Polarized light
Non-polarized light
lenses
lenses
receiver
emitter
receiver
emitter
Shiny object
Polarized light
Polarized light
Polarization filter
Reflectors Positioning of reflectors
right -The reflector is aligned and centered
wrong - The reflector is tilted more than 15°
wrong -The reflector is not centered
right The reflector should be smaller than the object
wrong The reflector is too big
Tilting the reflector by ±15°does not affect the direction of reflection
Diffuse Sensors
§ To detect and count objects with the same color and at the same distance
§ To detect black marks on white paper
§ To detect objects without interfering background
Proximity Sensors
• Measures reflected light intensity
• “Color” isn’t always color
• Light source color can matter
Contrast Sensors
Light on the foreground diode
Light on the background diode
emitter
lens Object in the foreground
(sensing range) Object in the background
Sensing distance
Only when the light falls on the foreground diode the sensor switches ON
Background Suppression
Strengths and Weaknesses Diffuse Sensors
o Strengths • Easy to Mount • Many Different Types / Modes
o Weaknesses • Less Reliable • Harder to Teach / Set
Light Barriers o Strengths
• Very Robust • Easy to Teach / Set Once Installed
o Weaknesses • Requires Additional Mounting • More Possible Points of Failure • May Not Be Possible in Application
Bridging the Gap with Baumer’s SmartReflect™
Technology
SmartReflect™ SmartReflectTM is a new technology for a new kind light barrier
Light barriers with SmartReflectTM technology…
• …do not require any special reflectors or even separate receivers
• …are easy to teach
• …Features a precise light beam
• …Standard verison is insensitive to dirt
The first and only light barrier requiring neither special light reflectors (corner cube or reflective tapes) nor a separate receiver for proper operation.
Just aim the sensor against any machine part within its range – Teach – and the light barrier is ready to go!
SmartReflect™
1. SmartReflectTM / Standard version • For detecting opaque targets
2. SmartReflectTM / Tray version • For detecting transparent trays &
boQles
3. SmartReflectTM / Foil version • For detecting thin transparent foils
SmartReflect™
Questions? Mike Jermann Design World [email protected] Phone: 330-322-2910 Twitter: @DW_MikeJermann
Corey Loeffelholz Baumer Ltd. [email protected] Phone: 262-416-2356
Christ Makris Baumer Ltd. [email protected] Phone: 708-712-8149
Thank You q This webinar will be available at
designworldonline.com & email
q Tweet with hashtag #DWwebinar
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