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Lightweight Road Wheel (LwRW)

Description:

TECHNOLOGY AREA(S): Ground Sea 

OBJECTIVE: Develop lightweight road wheel technologies, for marine and on/off road complex mission profiles, that use innovative materials, design, and manufacturing processes; reduce scheduling, manpower, and time constraints; and achieve increased cost efficiencies to translate into lifecycle cost reductions. 

DESCRIPTION: Currently, the Assault Amphibious Vehicle-Family of Vehicles (AAV-FoV) platforms (AAVP7A1 personnel variant, AAVC7A1 command and control variant, and AAVR7A1 recovery variant) share the same road wheel component as the U.S. Army Bradley Fighting Vehicle (BFV) (#12358464). The road wheels are made of forged steel integrated with rubber that incur a substantial weight penalty of 2,011 pounds (24 wheels) per vehicle. The Marine Corps seeks the development of a new road wheel, made of strong yet lightweight materials with either abrasion resistance coating or innovative lightweight steel wear plate designed to sustain track center guide’s abrasion impact without track derail concern. This lightweight wheel design should be able to reduce fuel consumption and prolong the rubber tire life, while increasing interval time between maintenance operations. This topic seeks to explore innovative and alternative road wheel system designs for military vehicles. Of particular interest are concepts that satisfy the following criteria: • Reduce road wheel weight by >40% (BFV steel road wheel - 83.8 lbs./pc) • Reduce or eliminate galvanized corrosion concern • Decrease lifecycle cost • Increase time interval between maintenance • Improve maintainability efficiency • Decrease fuel consumption • Improve rubber tire life with min. average life of 2000 miles under AAV-FoV configuration The lightweight road wheel systems shall operate in basic water, and on primary and secondary roads, trails, and cross-country conditions. Basic water conditions are of salt and fresh, open ocean, surf zones, lakes, rivers, streams, marshes, swamps, snow, slush, and ice. Primary roads are high quality paved, secondary pavement, and rough pavement surfaces. Secondary Roads are loose surface, loose surface with washboard and potholes, and Belgian block surfaces. Trails are one-lane, unimproved, seldom-maintained, loose surface roads intended for low-density traffic. Typically trails have no defined road width, large obstacles (rubble, boulder, logs, and stumps), cross ditches, washouts, steep slopes, and no bridging/culverts. Cross-country terrain can consist of tank trails with crushed rock or having large exposed obstacles (rocks, boulders, etc.), but there are no roads, routes, well-worn trails, or man-made improvements. This includes but is not limited to flat desert, marshes, vegetated plains, jungle, dense forest, mountains, and urban rubble. The system shall be operable and maintain Full Operational Capability (FOC) under the operational conditions as follows: • Tracked platform with six stations per side * Roadwheel size: OD 24 inches • Road wheel impact load cases: 3.5g [vertical], 2g [vertical] @ rim edge, 3g [lateral], and combined (2.5g [lateral] + 1.5g [vertical]). 1g = 8000 lbf (nominal vertical load) • Road wheel fatigue load cases: 1g @ rim edge with a minimum 1.55M cycles life; Combined (1.2g[vertical]+.25g[lateral]) with a minimum 1.55M cycles life • Lateral slopes of up to 40% capable of sine wave operation • Ascending / descending grades of up to 60% • Trails grades up through 40% • Maintain 64.37 kph (40 mph) forward speed on level Primary Roads • Accelerate in the forward direction from 0 to 20 mph (32.2 kph) in 10.5 seconds or less on a dry, hard, level surface • Stop within 15.24 meters (50 feet) from the forward speed of 32.2 kph (20 mph) on a dry, hard, level surface with a drift not to exceed 0.91 meters (3 feet) in the actual stopping distance • Capable of 360 degrees pivot steering turn within 45 seconds or less • Discrete obstacle negotiation, including vertical step (36”), gap (8’), and trench crossing • Sustain riverine operation • Ascend a 91 cm (36 inch) vertical obstacle in the forward and backward directions without preparation vehicle • Ambient air temperatures from -51º C (-60º F) to +52º C (125.6º F) 

PHASE I: Develop wheel concepts to reduce weight and to improve the service life of road wheel system by exploring the use of alternative materials, design, maintainability, and manufacturing techniques that meet the requirements outlined in the Description. Develop test methodology for operations in marine environments and rubber tire durability that evaluate the expected life of lightweight road wheel systems. Demonstrate the feasibility of the concept in meeting the Marine Corps requirements. Establish the wheel design feasibility by material sample testing and analytical modeling to deliver the promised performance and capability, as appropriate. Provide a Phase II plan that identifies the verification approach of performance goals, key technical milestones, and addresses technical risks. 

PHASE II: Develop prototypes and a process for testing. Evaluate the prototype to determine if the performance goals defined in the Phase II development plan and the requirements have been met. Demonstrate system performance through full-scale field testing to include durability and environmental performance. Use results to refine the design to optimize the performance. Prepare a Phase III plan to transition the technology to the Marine Corps. 

PHASE III: Complete full-scale application, testing, demonstration, implementation, and commercialization. The Marine Corps could buy future lightweight road wheel system through a Phase III contract if the performer has the manufacturing capacity. The Marine Corps could also use the results of this effort to update standards in future competitive contracts that would facilitate a teaming arrangement with a company that could produce the quantities required for future acquisitions and sustainment. The technologies developed under this SBIR effort would have direct application to other Department of Defense applications including other services’ lightweight road wheel systems on Tactical Vehicles, Heavy Equipment, and Industrial Equipment. The technologies developed under this SBIR topic would be of interest to industrial, agricultural, and recreational vehicles. The technologies would also have applications for large bulldozers, excavators, graders, and farming equipment used in mining, construction and farming industries. 

REFERENCES: 

1. AMCP 706-356, AMC Pamphlet: Engineering Design Handbook – Automotive Series – Automotive Suspensions. U.S. Army Materiel Command: April 1967.; 2. Wong, Jo Yung. “Theory of Ground Vehicles, 4th Edition.” New York: A Wiley-Interscience Publication, 2008.

KEYWORDS: Tanks; Rubber Compounds; Cold Spray Coating; Composite Materials; Reinforcement Rings; Wear Plate; Induction Hardening; Stress Releasing; Coatings; Sprays; Armored Personal Carrier APC; Aluminum; Solid Rubber Wheel; Amphibious; Fuel Savings; Combat Vehicle; Heavy Weight; Component Durability; Reduced Life Cycle Cost 

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