The system is composed of a mobile unit and a fixed unit.
The mobile unit includes a sophisticated video camera installed on the service balcony of the rolling trolley that moves along the tower crane's jib.
The camera, which has a zooming range, travels with the trolley along the jib and broadcasts images of the operating field constantly and wirelessly to the operating cabin.
The fixed unit is installed in the operating cabin and includes, among others, a video receiver compatible with the transmitter and a high-quality, high-resolution colour screen. Thus, the operator can clearly see the operating field at all times and constantly follow the loading and unloading zones, as well as the hook and payload's path.
The system is designed primarily to solve the problem of crane operators' blind spots, which is a known operational and safety problem on many construction sites. These blind spots are a safety risk that slows the work of the tower crane. As the main transportation vehicle in modern day construction sites, the crane tends to form a bottle-neck in the progress of work on-site. On-site time studies show that the cycle shortening achieved Crane Vision's visual system is of several ten percent, depending on site conditioning and the particular payload.
The visual system is of great use in a wide range of cases, for example – it improves crane operation under poor lighting conditions, it assists the operator in accurately placing the hook above pre-cast elements, it allows the crane operator to visually supervise the securing of the payload, it increases work safety near power lines and other obstacles, and it prevents accidents on sites where there are multiple cranes with overlapping reaches.
Among the key advantages of the Crane Vision visual system, are:
CVS-9 is a convenient, user-friendly and efficient system. In the words of a long-time carne operator: "this camera is the best thing that has happened to me in my thirty years as a crane operator". The visual system has several key advantages, each of which is reason enough itself to invest in it:
Safety – the system contributes significantly to the safety of the crane operation by enabling the crane operators constant eye contact with the payload from the moment loading begins until it is fully unloaded. Both from a financial point of view and in terms of public image, the prevention of one accident in five years would be enough to justify the use of this system.
Reduction of payload transfer cycle – in a controlled study conducted at the Israeli Institute of Technology – the Technion, an average reduction of 30% was measured in the cycles of typical construction operations. For example, lifting and placing pre-stressed concrete elements, under convenient conditions (without vision disruptions or great distance); each cycle took 4 minutes with the system, as opposed to 6-7 minutes without it.
Reduction of project length – several minutes' reduction for each lift, accumulated over several months, adds up to a long time, and shortens the length of the entire project be several weeks, thus indirectly saving hundreds of thousands of NIS. These savings are also expressed in the avoidance of substantial fines for delays to the schedule (conversely, in the receipt of bonuses for schedule advancement) and reduction in funding costs due to project length shortening. The direct and indirect financial savings are orders of magnitude greater than the cost of the system.
Minimization of wear and maintenance costs – through smoother, finer more precise operation of the tower crane, the mechanical and accidental wear on the crane is significantly reduced (motors, gear boxes, clutches, breaks etc.). The fatigue of structural elements (such as welds) and cable wear are reduced as well. In addition, the systems spares the need to frequently change cables, thanks to the operator's ability to view the exact location of the hook and avoiding friction with buildings even when it is out of direct view. According to equipment managers at construction companies, this benefit alone, combined with reduced down time for maintenance and repairs, saves over 35,000 NIS a year.
Work under poor lighting conditions or in the dark – during night shifts, when construction teams work under floodlight, as well as in the dim light of dusk and dawn – working with the high-quality CVS-9 camera is safer, quicker and more efficient, as the crane operator has a bright on-screen display of the work field. For projects operating in the dark, this system is vital, and this aspect alone financially justifies its use.