RS Technologies offers the widest range of wheel force measurement for road load data acquisition applications for small passenger cars on up to heavy trucks! The sensors can also be used for bi-axial test rig load verification or road simulator calibration. Our deisgn is so flexible that the same heavy truck sensor can be used in several configuarations: steering axle, tandem rear, or with the new super-single! All RS Tech WFTs have the following features:

• Single piece flexure for rugged, reliable and durable testing
• Superior temperature compensation
• Durable, splashproof and water-resistant sensor and electronics
• Six-component road load measurement: longitudinal force, vertical force, axial force, turning moment, overturning moment, axial moment
• On-board preamplifier and calibration circuitry for each channel of measurement
• Easily integrated into modern state of the art road load data acquisition systems
• Compatible with virtually all data acquisition systems

Bi-Axial Tire Test Rig Configuration

Durable High Accuracy Sensors

The WFT from RS Technologies is comprised of a durable, one-piece sensing element. The one-piece sensor design helps to ensure that calibration and crosstalk characteristics of the sensor will not change following calibration or during a test. It also provides linearity over the complete operating range and minimizes the chance of problems due to the loosening of bolted assemblies utilized by other manufacturers.

Based upon over 30 years of development, actual application engineering, and continual improvement, the result is a highly refined design that is built for use under severe loading and environmental conditions like off-road handling and short-term submersion, and yet provides superior measurement performance.The road load wheel sensors and torque wheel sensors from RS Technologies are multi-component transducers designed for comprehensive measurement of road load force, torque, or both on an automotive, light truck, or heavy truck wheel.

The road load wheel sensor is a six-component design that features a proprietary, advanced one-piece sensor section that is extremely rugged yet provides highly sensitive readings. The road load wheel is designed to measure three forces and three moments on an automobile or truck wheel: longitudinal, lateral, and vertical forces along with turnover moment, wheel torque, and turning moment.

The RS Technologies WFTs come in a wide range of capacities to fit test requirements for subcompacts, standard passenger cars, light trucks, and heavy trucks. Hub adapters and modified rims can also be provided to adapt the sensor to the test vehicle.

WFT or Torque Wheel

For less complex testing of driving power and braking performance, RS Technologies can provide you with Torque Wheels. In addition, special units can be configured for measurement of rolling resistance drag for tire performance.

Heavy-Duty Sealed Sensor

All RS Tech WFTs are heavy-duty, on-vehicle sonsors that can handle the bumps, jolts, and splash of typical road driving. The wheel sensors can accept extreme load inputs during the most demanding road surface tests, yet they also have the resolution and sensitivity to measure tire tread friction forces. The wheel sensors are rugged enough to withstand road abuse and can even be subjected to short-term submersion, even when outfitted with telemetry electronics.

WFT w/Telemetry

The road load or torque wheel sensors provide output signals in real time to the CADA package via either a conventional slip ring or an advanced telemetry signal transmission unit as shown on the left.

Both wheel sensor types include an integral angle position encoder that provides speed and position monitoring. This is particularly useful for ABS/traction control studies and differential performance analysis.

Through the use of CADA, the Transducer Interface Unit (TIU) has become fully integrated into the data acquisition system, providing for dynamic force, torque, and position communication between the wheel sensor and the data acquisition system. The TIU consists of the power supplies and signal conditioning electronics that convert the WFT signals into equivalent signals referenced to the wheel axes. The TIU can support four WFTs and provide up to 96 channels for additional inputs in standard 8.5-inch or 19-inch rack mount type package.

Quick Setup of WFT with CADA

Through use of our unified approach, the mounting, adjustment, and setup of the WFT using the CADA system is very straightforward and easily accomplished. When proper cabling and restraints are available, initial start up takes about 20 minutes per wheel. From a cold start, 10 minutes are required to warm up the system. The initial non-running adjustment takes 3-5 minutes per wheel. A full recheck and readjustment can be done as needed dynamically while driving. Rapid setup techniques allow verification of proper operation of all measuring elements and the same sequence can be used immediately following a test run to verify that the equipment has maintained original setup.

Calibration Services

RS Technologies has a state-of-the-art facility and an experienced staff to provide complete diagnostic, repair, and calibration services for all makes of road load and torque wheels. All torque and force calibration services are accredited by A2LA according to ISO Guide 25 and traceable to NIST standards.

IMPORTANT NOTE: RS Technologies highly recommends that all WFT systems (including sensors, electronics, and cables) be returned to the factory on an annual basis for inspection, calibration, and installation of upgrades. Only in cases of extremely light use the systems should be returned every two years.