Evaluation of Alternate Driveshaft Configurations for the FMTV Program. Part 3 of 3

Abstract

The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, ^^f!'*' '"2,.l'^f^l'?ht^^iS^iS^% I lie liuL^tiu icpwi %»y _«« "";"..,:-tKa ^^u^r^'.nr, «* intntmotinn Ranrt rrtmmemts ronarriina this burden estimate or anv other aspect or this collection 01penalty for failing to comply with a collection of information If it does not display a currently valid 0MB control number. 01-04-199801-04- TO 28-02-2003 5a. CONTRACT NUMBER PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. REPORT DATE (DD-MM-YYYY) DAAE07-98-C-M0125b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)MICHIGAN SCIENTIFIC CORPORATION 730 BELLEVUE AVENUE MILFORD, MI 48381 SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)UNITED STATES ARMY-TACOM WARREN, MI 48397-5000 JAMES YAKEL, COTR PERFORMING ORGANIZATION REPORT NUMBER A005 SPONSOR/MONITOR'S ACRONYM(S)N/A The FMTV provides a cliaiienging environment for driveshaft applications. Long driveshafts are of concern because of critical speed issues. Large operating angles on cardan joint driveshafts are also of concern because of torsional acceleration issues. Both concerns are exacerbated by high driveshaft rotational speeds. The FMTV has driveshafts that exceed the limits of the traditional design envelopes on these three design features: length, operating angle, and rotational speed. SPONSOR/MONITOR'S REPORT NUMBER(S)N EVALUATIONS OF CANDIDATE DRIVESHAFTS FOR THE FMTV PROGRAM FROM DANA, ARVIN MERITOR (2 DESIGNS), AND GKN WERE CONDUCTED. THE EVALUATIONS INCLUDED INSTRUMENTED ROAD TESTING, A 1000-MILE DURABILITY TEST THAT INCLUDED HIGH SPEED DRIVING AND SUBMERSION, LABORATORY MEASUREMENTS, AND DADS MODELING. THE DRIVESHAFTS WERE (UN)BALANCED TO THEIR MANUFACTURERS PRODUCTION LIMITS PRIOR TO EVALUATION AND THEN TESTED ON THE VEHICLE USING A SPECIAL TRANSFER CASE TRANSDUCER CAPAPBLE OF MEASURING DRIVESHAFT DYNAMIC FORCES. A PRINCIPLE FOCUS OF THE PROGRAM INCLUDED SEVERAL METHODS OF MEASURING INSTALLED CRITICAL SPEED. SUBJECT TERMSThe FMTV was designed to meet a wide array of state-of-the-art performance requirements that expanded the mobility and utility of the vehicle, but also led to the need to push components and sub systems to the limits of practibility. Some of the performance requirements that challenged the design include:• The FMTV was required to meet the low speed/high torque requirements of the cooling test. It also had to meet high speed trailering and grade climbing requirements. These combined performance expectations drove the need for a seven speed automatic transmission. The seven-speed Allison MD-D7 transmission with two overdrive gears (derived from a production six speed transmission) was developed in order to meet these requirements.• The FMTV trucks are required to climb up a twenty-four inch high vertical step. This requirement leads to the need for a high clearance transfer case. The o...