Biaxial wheel test assembly

A method of testing a wheel-and-tire assembly using a biaxial wheel test assembly, the test assembly including a drum and a wheel force transducer, the method comprising the steps of:

• rotating the drum at a first predetermined speed;
• engaging the rotating drum with the wheel-and-tire assembly;
• applying a radial force to the wheel-and-tire assembly measured with the wheel force transducer generally equal to a radial force set point;
• applying an axial force set point to the wheel-and-tire assembly measured with the wheel force transducer generally equal to an axial force set point;
• measuring a camber moment of the wheel-and-tire assembly with the wheel force transducer;
• and
• controlling a camber angle of the wheel-and-tire assembly in response to measuring the camber moment.

A method of controlling a biaxial wheel test assembly for simulating driving loads, the test assembly including first, second and third actuators for controlling an axial force, a radial force, and a camber angle of a wheel-and-tire assembly to be tested, the test assembly further including a rotating drum with inner and outer rings and a wheel force transducer, the wheel-and-tire assembly being urged against the rotating drum and the inner and outer rings with the first, second and third actuators, the method comprising the steps of:

• adjusting the radial force based on a radial force set point previously determined during vehicle testing;
• adjusting the axial force based on an axial force set point previously determined during vehicle testing;
• measuring a camber moment based on the axial force and the radial force;
• and
• adjusting the camber angle based on the measured camber moment.

A method of testing a wheel-and-tire assembly using a biaxial wheel test assembly, the test assembly including a drum and a wheel force transducer, the method comprising the steps of:

• rotating the drum at a first predetermined speed;
• engaging the rotating drum with the wheel-and-tire assembly;
• applying a predetermined camber angle to the wheel-and-tire assembly;
• applying a radial force to the wheel-and-tire assembly measured with the wheel force transducer generally equal to a radial force set point;
• applying an axial force to the wheel-and-tire assembly measured with the wheel force transducer generally equal to an axial force set point;
• and
• maintaining simultaneously the axial force generally equal to the axial force set point, the radial force generally equal to the radial force set point, and an axial-force-via-moment generally equal to the axial force set point.