Sensors: Driving forward to boost productivity
22 May 2017
To meet the need for improved productivity, the trend for off-highway vehicles has been to move away from discrete hydraulic controls to fully-electronic operator controls. These trends, together with customer requirements, have changed Curtiss-Wright Industrial division’s approach to design and manufacturing
Curtiss-Wright Industrial – and its Arens Controls, Penny & Giles, PG Drives Technology and Williams Controls brands – is a leader in the research, design and manufacture of critical controls and assemblies, including sensors, electronic throttle controls and joystick controllers for on- and off-highway specialty vehicle applications.
These controls are designed to improve vehicle reliability and operator comfort. They also help increase the productivity of vehicles, improve safety and reduce manufacturing costs.
Rapid-design techniques, including computer modelling, have played a significant role in reducing the cost of design, with far less time and therefore money devoted to prototyping. For manufacturing, reduced component counts thanks to improved technology and CANbus wiring systems – which further lessen the material used – have contributed to cost-effective designs and a positive impact on reliability.
Technology in action
Curtiss-Wright Industrial supplies electronic throttles to Polaris Industries for use on its RANGER and RZR XP 1000 vehicles.
As vehicle volumes increase, Polaris Industries Inc, a designer and manufacturer of high quality off-road vehicles (ORVs), including all-terrain vehicles (ATVs), snowmobiles, motorcycles and on-road electric/hybrid powered vehicles – is opting for Williams Controls throttles as part of a move away from conventional push/pull mechanical systems to electronic control.
Engineering teams from both companies worked together for 18 months to re-engineer a Williams Controls pedal design, with the resulting electronic pedal needing to be sized and ergonomically shaped to suit the compact in-cabin dimensions of the then all-new RZR XP 1000.
During the product development phase, the Williams Controls team engineered a new spring design and, using its in-house rapid prototyping facilities, an altered lever arm. The updated specifications for the electronic throttle also included the use of an integrated, non-contacting Hall-effect sensor providing two independent linear output signals proportional to pedal position. This sensor provided feedback directly to Polaris’ latest throttle management system – credited as providing the fastest acceleration, highest top speed and flattest torque curve in the industry – to provide much-improved control.
What seemed like relatively simple design changes to the existing pedal actually required a complete revalidation of the Williams Controls custom pedal to ensure its suitability for both Polaris applications. This included testing it for both U.S. and European market requirements and a series of environmental assessments.
Despite some of the harshest tests ever carried out on its products, the pedal and sensor out-performed the requirements of both companies. In fact, for the corrosion resistance test conducted in a salt fog chamber, the custom pedal far exceeded Williams Controls’ own 96 hour requirement and easily met the Polaris requirement of 336 hours.
Commenting on the stringent testing requirements, senior vice president and general manager of Curtiss-Wright’s Industrial division, Kevin Rayment, explains that, given the conditions Polaris vehicles have to endure, they are delighted with the results: “It’s not unusual for these recreational vehicles to be found driving through swamps or in muddy water up to the driver’s waist, so to not just pass but exceed these somewhat unique requirements is a testament to our design, engineering and manufacturing processes.”
Vehicle operators have had a lot to cope with over the years, yet arguably the harshness of their working environment – with inherent dust, vibration and environmental hazards – has remained the same. However, the sensor and control industries have continued to develop technologies that protect and improve the experience of off-highway vehicle operators.
Curtiss-Wright engineers are focused on developing bespoke, innovative solutions and next generation technology. This intelligent engineering, from initial concept to finished product, demonstrates the Industrial division’s commitment to providing the advanced control and power management systems demanded by today's on- and off-highway vehicle manufacturers.