Track trailers, such as this log loader, using an ASV undercarriage, might be useful tools in many applications.
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Now and then Construction Equipment editors run across what seems to be an emerging product category, and such it is with rubber-track hauling machines, typically identified as "crawler carriers" or "crawler utility vehicles" or "all-terrain carriers." Although these units have been around for a while, we're hearing more about them from manufacturers such as Hitachi, IHI, Komatsu, Morooka and Yanmar, which, collectively, have 18 basic models ranging in horsepower from 10.4 to 400, and in operating weight from 2,200 to 35,000 pounds.
It's a bit unclear just where the line falls among these models to separate dedicated haul units from those having a more multipurpose character. But one of the newest entries in this product category, the ASV Scout SC-50, is definitely in the latter group, reflecting a utilitarian design, which, according to Brad Lemke, ASV's director of product development, will allow the Scout to work effectively in a wide range of applications, including construction.
The Scout's overall design and its potential for application versatility prompted Construction Equipment editors recently to visit ASV at its Grand Rapids, Minn., headquarters for a hands-on introduction to the new machine. We spent the better part of a day with Lemke and Hannah Tanata, product-marketing manager, who explained that the Scout is a logical extension of ASV's rubber-track-loader technology.
But ASV is hardly a newcomer to the rubber-track-carrier market. When the company opened its doors in 1983, its first product was the Track Truck, a half-track vehicle designed as a year-round, all-terrain transporter. When Track Truck users began to push the vehicle beyond its design limits by equipping it with homemade attachments, the new company turned its engineering expertise toward developing rubber-track loaders with legitimate attachment-handling competence. From that beginning, the present Posi-Track loader line has emerged.
So, in a way, ASV's product-development efforts have come full circle, because the new Scout SC-50 uses much of the proven technology embodied in Posi-Track models. The Scout, for example, is fitted with an oval-track variation of the company's proprietary rubber-track undercarriage, the R-Series Traction and Support System (RTSS), which employs multiple rubber-rimmed wheels to spread machine weight evenly over the tracks.
Each of the Scout's track assemblies uses 10 such wheels — eight bogies (smaller wheels) and two larger idlers. With 59 inches of track-on-ground, the 15-inch-wide, proprietary rubber tracks provide a total contact area of 1,770 square inches, yielding an approximate ground pressure of 2.5 psi. And like Posi-Track models, the Scout's undercarriage uses a roller-type sprocket, and its track frames are suspended with torsion axles (two per track frame), which have the ability to flex in rough terrain. The undercarriage is virtually maintenance-free, having only two grease fittings per side.
The Scout's power train is similar to that of the Posi-Track RC-50 loader, using the same four-cylinder, 46-net-horsepower Perkins diesel engine and nearly identical Rexroth hydrostatic-drive system. The point, says Lemke, is that this combination of design elements gives the Scout the needed performance characteristics for its various potential applications, but does so by using much of the proven content of ASV loaders.
Design innovation
But the new Scout also exhibits its own brand of innovation. Its optional dump body, for example, can be quickly mounted (or removed) from its large, flat, diamond-plate rear deck, which can be fitted with cargo-restraining side rails when the dump body is off. An optional auxiliary hydraulic system, which delivers 16.3 gpm at 3,000 psi, provides quick-connect fittings at the back of the cab for powering deck-mounted equipment, and at the front bumper for front-mounted attachments.
The Scout also is the first ASV machine to use an electro/hydraulic joystick for auxiliary-hydraulic control. Two slender wiring harnesses link the joystick to the auxiliary control valve, eliminating the pilot valve and plumbing associated with a conventional auxiliary system. The joystick allows, for example, lift, lower and angle functions for a front snow blade, plus raise and lower functions for the dump box (via an integral thumb control). A trigger on the joystick controls a float position for front attachments.
ASV also has simplified steering and directional control with innovation. On the steering shaft, just forward of the cowl, are two thick plastic cams that rotate with the steering wheel to control the movement of two spring-loaded plungers in a pilot valve, which regulates oil flow in the drive system. In similar fashion, for directional control, a large floor-mounted "quick-shift" pedal rocks side-to-side to allow instant (and smooth) forward/reverse changes.
These features do make the Scout an easy and intuitive vehicle to drive. We found the steering sensitive at first, and it took a few maneuvers to get the hang of steering-wheel-movement-to-track response, but it's a technique soon mastered. As a safety feature, each occupant must have a seat belt fastened, and the operator must push an "unlock" button before the Scout will move.
According to ASV, the combination of the Scout's beefy frame, good weight distribution and strong undercarriage accounts for the machine's considerable hauling and towing capacities. In standard trim, the Scout has an operating weight of just over 4,500 pounds, but can handle a 4,000-pound load on its 24-square-foot deck, or 3,300 pounds in its 1.3-cubic-yard dump box. Towing capacity in either configuration is 5,000 pounds. Along with other potential deck-mounted attachments (a concrete mixer, core-drilling/soil sampling package or fire-fighting apparatus, for instance), additional front-mounted attachments (perhaps sweepers and augers) will be developed. Currently under development is a Category-1, three-point hitch for attachment use at the rear of the vehicle.
Also under consideration is a utility package that would allow using the Scout's auxiliary hydraulic system to power a variety of hydraulic hand tools. And for logging and landscaping, or in any application requiring a machine that leaves no footprints, the Scout can be fitted with ASV's smooth turf tracks, which leave the ground virtually undisturbed. ASV is working with a number of partners in a wide range of industries to develop application-specific work packages, says ASV's Tanata, and will investigate and expand this offering to meet customer requests.
The base configuration of the ASV Scout SC-50 has a suggested list price of $26,495. The basic Turf Edition, with smooth tracks, lists for $28,495.
