HIGHLY dynamic and accurate measurement; multifunctional switching outputs and inputs for stand-by, preset and other system functions; a device display with all important information available at a glance; and a particularly user-friendly mounting and alignment concept are the most important advantages of the new DME 5000 laser distance measurement system from SICK Australia .
The light and compact device, to be presented for the first time at the SPS/IPC/DRIVES 2002 trade fair in Nuremberg, is available in two versions that have been specially optimised for automatic small parts stores or for pallets in high-bay warehouses.
Moreover, the DME 5000 is the only device of its type that is approved by CSA and UL.
The DME 5000's ambient temperature range has been designed for +55°C to -10°C. A variant with internal heating achieves +55°C to -40°C. Thus the distance measurement device is also suitable for use in deep-freeze storage systems.
Two warehouse types of differing sizes predominate: automatic small parts stores for containers of varying dimensions, and structurally larger high-bay warehouses for Euro and, sometimes, system-specific pallets.
The new DME 5000 is suitable for approach speeds of up to 10m/s and takes the differing requirements of the two types of warehouses into account with its two range-optimised versions for 70m and 150m.
The 70m version is characterised by highly dynamic shelf behaviour: a current measurement value is provided each millisecond.
A variety of improvements, including the sensor's reduced temperature drift of 0.1mm/K, ensure an accuracy of ±2mm with a reproducibility of 0.5mm, thus achieving extremely rapid and accurate positioning of the storage and retrieval units at container spaces.
The 150m variant of the DME 5000 is the right choice for high-bay warehouses with their longer vehicle paths and larger pallet spaces.
It provides a measurement value every two milliseconds with an accuracy of ±3mm.
So particularly rapid positioning processes are possible here too.
Whether the 70m or 150m variant - both versions of the DME 5000 share important device features that are particularly appealing for users.
During commissioning, and also during subsequent operation, the illuminated display shows all important status diagnosis functions at a glance.
The visible red light beam, and the horizontally and vertically adjustable alignment mounting on which the DME 5000 can be reliably secured with just three screws, simplify installation. SSI and Profibus interfaces are available for the user.
There are also two multi-function switching outputs (e.g. for predefined distance values), and temperature warnings or a pre-breakdown message can also be programmed as inputs.
It is therefore possible to use one of the outputs as an input via which the DME 5000 can be activated by an external signal. In stand-by mode the light transmitter is only started up if needed.
A further system option is the preset function with which a quicker and more millimetre-accurate calibration between the measured expected position and the actual position of the storage and retrieval unit in the aisles is achieved during commissioning of the DME 5000 - by approaching an initiator as a reference mark.
Both functions, stand-by and preset, can alternatively be carried out via the Profibus interface.
Distance measurement systems such as the DME 5000 are used in automated storage technology for detecting the position of storage and retrieval devices.
In order to do this, the sensor moves with the vehicle and constantly measures the time-of-flight of an emitted light impulse to the end of the shelf aisle and back.
The electronics unit determines the position of the storage and retrieval unit from this time and passes it on to the vehicle control system.