View

Click to View WIM Video

Weigh-In-Motion System

Today’s military forces must maintain the capability to rapidly project massive combat power anywhere in the world with minimum preparation time. Currently, units use portable individual wheel weight or fixed in-ground static scales, tape measures, and calculators to determine vehicle axle weights, total vehicle weight and center of balance for vehicles to be transshipped via railcar, ship, or airlifted in support of military and humanitarian operations. The process of manually weighing and measuring all vehicles for transshipment operations is time-consuming, labor-intensive, and most importantly is prone to human errors that can result in safety hazards and inaccurate data. In austere areas of operations, scales may not be available at all, and the cargo weight and center of balance must be estimated. This process is even more susceptible to human error. The lack of a standardized airlift-weighing system for joint service use also creates redundant weighing requirements at the cost of scarce resources and time.

The Weigh-In-Motion (WIM) system provides a man-portable means of accurately weighing vehicles (including wheel and/or track), cargo (pallets, containers) as each crosses the scales and determining axle weights and spacing for vehicles, total vehicle/cargo weight and longitudinal center of gravity. The WIM system can also weigh the above statically. Because of the automated nature of the WIM system, it eliminates the introduction of human errors caused by manual computations and data entry, adverse weather conditions, and stress. Individual vehicles can be weighed continuously at low speeds (approximately 3-10 mph) and at intervals of less than one minute. The system requires only two men to operate, versus six to eight for its portable single wheel weight scale counterpart, and tests have demonstrated that it can speed up the process by a factor of five.

The WIM system’s capability to rapidly weigh vehicles and determine their center of balance will enhance the rapid and safe deployment of the force. Deploying and supporting units can set up their TOE portable WIM systems at home stations, ports of embarkation, intermediate staging bases, ports of debarkation, theater staging bases, and austere airfields in accordance with the combat, combat support and combat service support requirements of the geographic combatant commander.

The prototype WIM Gen I was tested during a field demonstration at Pope AFB/Ft. Bragg, NC, in May 2005.  Using the results of this demonstration, the Army units that tested the WIM GEN I recommended enhancements to determine the best application of new weighing technology and automated interfaces. ORNL enhanced that prototype to a field-ready prototype (WIM Gen II) incorporating state-of-the-art technologies to capture automated vehicle identification, determine the weight and center of balance, update that real-world “actual” data electronically into AALPS for load planning and manifesting purposes, and then to TC-AIMS II for in-transit visibility for operational planning, deployment and execution purposes.