Surface Removal System And Method

Description (excerpt)

CROSS REFERENCE TO OTHER PATENT APPLICATIONS The present application is a divisional of and claims priority to U.S. patent application Ser. No. 17/300,010 filed Feb. 5, 2021, which claims the benefit of U.S. Provisional Patent Application No. 62/918,724 filed under Docket No. 112516—PR on Feb. 10, 2020 and titled: Surface Removal System and Method, the complete disclosure of each are incorporated herein by reference. STATEMENT OF GOVERNMENT INTEREST The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor. BACKGROUND OF THE INVENTION To mechanically remove layers of material from predominantly vertical substrates, very limited solutions exist. At many locations, such as shipyards and industrial facilities, this operation is performed by using handheld power tools to remove the material, such as for example, epoxy, from a substrate. One operator will “filet” the layer as close as possible to the substrate while another operator pulls the layer away by hand or by use of ropes and clamps. This method is extremely unwieldy when performed above chest height. When performed in any capacity for long periods of time, this method causes chronic injuries, such as carpal tunnel and a similar syndrome in the shoulders. In severe cases these injuries can lead to the medical retirement of the worker. These manual methods are also frequently performed many stories above the ground or at elevation when the surface under repair is large. Such operatives require full protection, safety training, and other operational risk mitigations to protect workers and avoid severe injury or death. These protections, while necessary, are costly to implement. This method is also slow and generally less efficient than desired, requiring many labor hours and consuming many resources in the process. Other methods exist for removing surface layers, however these methods involve burning, chemically altering, or otherwise directing energy to denature the undesired layers. These methods generate hazardous smokes, slurries, airborne dust, or other non-solid contaminants. Safely implementing these chemical removal technologies requires environmental permitting, worker safety analysis, and issuance of appropriate personal protective equipment to workers. Such operational protections are also costly to implement and if improperly executed can also result in worker injuries. Time spent by workers on the job may be restricted to limit exposure to these hazards. These restrictions on the amount of time work can be performed by an individual worker may cause an additional shift of workers to be added to the job. Thus, labor costs to complete the removal task on a given schedule are greater than those required on other tasks. Optionally, the schedule required to remove the material is lengthened since work can only be conducted for a fraction of the time available in a typical work week. SUMMARY OF THE INVENTION The present invention includes recognition of the problems and disadvantages of prior art methods and devices. The invention, surface removal system and method of the invention, provides significant improvements over existing techniques. According to one aspect of the invention, an operator performs the layer removal without use of a manual tool, eliminating common injuries associated with this work. According to one aspect of the invention, an operator uses a hydraulically controlled arm to remove adhered layers of material from durable substrates of virtually any size or shape, including vertically tall and overhead structures. The invention thus does not require use of scaffolding, fall protection or other complex safety requirements normally required when workers work overhead. According to another aspect of the invention, an operator can also perform this job more efficiently than using, for example, an excavator mounted fixed blade, because the invention maintains alignment of a blade over a large sweep of surface, allowing the operator to process an area with few readjustments of the main machine. This facilitated alignment and subsequent consistent cutting pressure according to an embodiment of the invention allows the blade to cut cleanly and remain very close to the durable substrate, eliminating undesirable remnants. This aspect of the invention also facilitates removal of material from surfaces with complex shapes including curved and compound curved surfaces. According to yet another aspect of the invention, the mechanical scraping natu