3D Image Sensing Using Smart Pixel Technology. Shape, Size and Volume

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1 3D Image Sensing Using Smart Pixel Technology Shape, Size and Volume 3D image sensor

2 Evaluate Shape, Size, Volume in industrial applications 3D Image Sensing Solves a Variety of Applications Innovative solution to common industrial applications In material handling and logistics applications, standard 2D vision cameras are used for their large field of view. However, 2D vision cameras cannot supply the distance information needed for many applications. To compensate for this, standard sensors, such as photoelectrics, are used for distance information, but only provide a single point of data. Therefore, many sensors are needed to obtain an accurate reading. ifm s new 3D Image Sensor addresses these challenges by offering a sensor with a large field of view that measures distance using reliable time-of-flight technology. The 3D Image Sensor is the first industrial sensor that can detect objects in three dimensions shape, size and volume in real time. Material handling sizing Sizing packages Transporting, sorting and sizing products are common applications in material handling. Determining the gross dimension and volume of a package is crucial to proper traffic flow. Currently, to pre-determine package size, multiple high-cost scanners are used to measure all sides of a package to determine height, width and depth which adds cost and complexity. View package in 3D Palletizing and de-palletizing The 3D Image Sensor uses a standard algorithm to determine the gross volume of a package in its Field of View. The pixel array sends 3072 data points that can be used to determine the highest, lowest and average volume of an object in the Field of View. The sensor sends a signal to the main control indicating the size of a package.

3 Example: Bread baking process Production processes in fast-moving conveying lines can be monitored. The 3D Image Sensor can detect if pans are underfilled or overfilled for proper food production. Incomplete layer, box overhang In palletizing and de-palletizing applications, a robotic arm removes bulk material from a conveyor or storage location and stacks the material on a pallet. The challenge is detecting when a layer of product is complete or incomplete. If a stray box is left on a skid and is undetected, there's a risk that the robotic arm will crush the product. Pallet in 3D for layer level The PMD 3D sensor is mounted to the top of the palletizer. The sensor's 64x48 pixel array projects 3072 data points of reference onto the pallet. The sensor evaluates the entire layer of a pallet and sends an alarm output based on loading errors. Using the three-dimensional data, pallets can be removed without the risk of damage to other pallets. Bulk material level Level detection to prevent run dry conditions Currently, multiple sensors are mounted over a bin to detect the level of bulk material. Materials, such as grain or pellets, can shift within the bin creating hills and valleys, leading to incorrect level detection. An empty or "run dry" condition can cause machine downtime, place stress on equipment, and risk damage to components. Level of materials in 3D The efector PMD 3D sensor is mounted above a hopper or bin. The sensor's pixel array of 3072 data points spreads across the grain to detect the entire area. The high and low points are identified and can be used for direct output or averaged to provide a more accurate level of available space in the hopper. Vibratory conveyor volume Level of food product on conveyor Many single-point position sensors are needed to detect the level of bulk food products on a vibratory conveyor. The volume of delicate food products, such as potato chips, can become too concentrated on one area of the conveyor and begin to break from the weight of the chips. Or, product can spill off the sides of the conveyor without proper distribution. Food product images in 3D The 3D Image Sensor detects the highs and lows of food product on a conveyor. The sensor can see when the level of product is too high or if food is concentrating in one area of the conveyor. Monitored in real time, the sensor will help to prevent food breakage and overflows. Immune to ambient lighting The active light source and PMD pixel array are oscillated at the same frequency. The IR light is also phase shifted 90 at four separate intervals during the image capture to verify that the light received is from the active source and not from the environment. This patented SBi technology is the primary reason that the ifm 3D sensor can be mounted both indoors and outdoors with no impact from external ambient light.

4 3D Image Sensor using Time-of-Flight Distance Measurement PMD Technology The 3D image sensor is designed to evaluate size, shape and volume in industrial automation applications. The compact, easy-to-use sensor uses time-of-flight distance measurement and photonic mixing device technology to identify an object in its field of view. The integrated 64 x 48 smart pixel array projects 3072 points of reference onto an object, capturing the entire object in three dimensions. Active Lighting Active lighting combined with ifm s patented Suppression of Background illumination (SBi) technology allow the 3D sensor to be applied in all lighting conditions, both indoors and outdoors Time of flight principal This principle measures a distance based on the time it takes light to travel to an object and back to the receiver. Object Smart Pixel Pixel Array The PMD pixel array An integrated 64 x 48 pixel array captures the light. Each pixel within the array is able to compute the phase difference directly on-board the sensor chip. This built-in functionality allows the sensor to pre-process the signal, removing the need for expensive high-speed electronics. Smart pixel Each pixel has two gates that are controlled by an oscillator. Here, the electrons are converted into photons.the light information is sent from the PMD chip as the representative distance for that pixel, carrying the desired 3D information. Consistent measurement Variations in color cause challenges with traditional photoelectric sensors. White objects reflect more than dark gray objects. ifm s 3D sensor has minimized this impact creating a more consistent measurement throughout the color spectrum.

5 Object detection in three dimensions Determining the Field of View is important for level and volume applications. Determining the minimum object size is important for material handling applications such as transporting, sizing and sorting product. Determine the overall Field of View The 3D image sensor s Field of View consists of 64 x 48 pixels. The size of each pixel is directly related to the distance of the sensor to the object. For example, in the chart below, at 1 meter range, the average pixel size is 11mm x 11mm square. This creates a Field of View that is 840 mm x 580 mm in dimension. Increasing the sensor-to-object distance will create a larger Field of View; conversely, decreasing the sensor-to-object distance will create a smaller Field of View. Measuring range / distance Determine the minimum object size As the distance between the sensor and object increases so does the size of each pixel. The pixel size will determine the minimum size of the object that can be evaluated. For best results, ifm recommends that the minimum object size is at least two times the size of an individual pixel. These values can be found in the chart below. Minimum object surface should be at least two times the size of an individual pixel Field of View X = 64 pixels For example, at 0.5 meter the pixel size is 6 x 6 mm. At 1 meter the pixel size is 11 x 11 mm. Y Y X X Actual pixel size Actual pixel size Y = 48 pixels Measuring range/ distance [M] Length Width Average pixel Minimum object surface White 90% Grey 18% x 6 11 x 11 ±3 ± x x 22 ±3 ± x x 33 ± 3 ± x x 44 ±4 ± x x 55 ± 4 ± x x 65 ±4 ± x x 76 ± 4 ± x x 87 ±4 ± x x 98 ± 5 ± x x 109 ± 5 ± x x 120 ± 6 ± x x 131 ± 6 ± 20

6 Technical data Application area Electrical design Industrial automation applications Resolution: 64 x 48 pixels Part no. Sampling rate / switching frequency [Hz] max. 25 adjustable Unambiguous ranges [m] 6.5 (single frequency mode) / 48 (dual frequency mode) Illumination infrared (850 nm) Operating voltage [V] 24 DC (± 10 %) Current consumption [ma] < 1000 (max. 2500) Short-circuit protection, pulsed Overload protection Operating temperature [ C] Protection yes yes IP 67, III Dimensions 122 x 75 x 95 Materials Connections Parameter setting options Parameter setting interface O3D200 List price (USD) $ Housing: aluminum; lens window: polycarbonate; LED window: polycarbonate external trigger; max. 2 switching inputs / outputs; analogue output (configurable) via PC / notebook or 10-segment display and two pushbuttons Ethernet 10Base-T / 100Base-TX Accessories (optional) Cordsets Description Part no. List price (USD) Description Part no. List price (USD) Mounting set for rod mounting Ø 12 mm Mounting rod, 100 mm, Ø 12 mm, M10 thread, stainless steel Switched-mode power supply 24 V DC / 2.5 A E3D103 E20938 DN2011 $28.00 $8.00 $ Switched-mode power supply 24 V DC / 5 A DN2012 $ m PUR, M12 straight, 8 poles E m PUR, M12 straight, 8 poles E m PUR, M12 straight, 8 poles E11311 Parameter setting cable, 2 m, M12 D-coded / RJ45, cross-link E11898 $24.50 $29.50 $61.50 $41.50 Lit. No.: B80509 ifm efector North America ifm efector USA 782 Springdale Drive Exton, PA ifm efector Canada 700 Dorval Drive, Suite 503 Oakville, Ontario L6K 3V ifm efector Mexico Anillo Periferico Col. Hacienda San Jeronimo Monterrey, N.L ifm supports the development of responsible forest management worldwide. The FSC Mixed Sources Label means that the wood comes from FSC certified well managed forests, company controlled sources and/or recycled material.