Determining range information from an observation location to one or more objects in an environment is important for many applications. For example, range information can be used by a surveyor as one measurement to determine the location of object(s) in an environment. Range information, in conjunction with other information such as orientation of the object relative to the observation location(s), and the location information of the observation location(s) can be used to construct maps with topographic information, or other forms of representation showing the location of object(s), and/or contours of the object(s) in the environment.
In a known form, a range finding apparatus is provided at an observation location, and the apparatus includes a laser emitter to transmit a laser light beam towards an object. The light beam is reflected off the object and the reflection of light is detected by a sensor of the range finding apparatus. The time of flight of the light travelling from the laser emitter to the object, and from the object to the sensor is measured. This time of flight, in conjunction with the speed of light, is used to determine the range between the range finding apparatus at the observation location and the object.
Further forms of range finding apparatus include three dimensional scanners that determine multiple ranges at multiple orientations from the observation location. In one form, this includes a laser range finder that is steered to provide the multiple measurements at respective orientations. The measurements may be used to provide contour information of object(s) or even the environment surrounding the observation location. Such information may be useful for determining the size and shape of surrounding features in an underground mine.
Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present disclosure as it existed before the priority date of each claim of this application.