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Modern on-road vehicles have been making steady strides when it comes to employing technological advances featuring active safety systems. However, off-highway machines are lagging in this area and are in dire need for modernization. One chassis system that has been receiving much attention in the automotive field is the steering system, where several electric and electrohydraulic steering architectures have been implemented and steer-by-wire technologies are under current research and development activities. On the other hand, off-highway articulated steering vehicles have not adequately evolved to meet the needs of Original Equipment Manufacturers (OEM) as well as their end customers. Present-day hydrostatic steering systems are plagued with poor energy efficiency due to valve throttling losses and are considered passive systems relative to safety, adjustability, and comfort.

This paper discusses the application of displacement controlled linear and rotary drives in future mobile machines with automatic motion control. The presented new circuit solution for pump controlled linear drives with differential cylinder allows the replacement of today's valve controlled actuators. Furthermore a new robust control concept for position and speed control of secondary controlled drives, which allows a rapid and easy implementation procedure was developed in the research group of the author. Its application for several rotary drives including its use for special propel drive concepts is briefly discussed. Due to the displacement control in case of aiding loads brake energy can be stored hydraulically or used by other actuators. This is why the presented new drive solutions can help to reduce operating costs and contribute to an environment-friendly machine design.

Original equipment manufacturers and their customers are demanding more efficient, lighter, smaller, safer, and smarter systems across the entire product line. In the realm of automotive, agricultural, construction, and earth-moving equipment industries, an additional highly desired feature that has been steadily trending is the capability to offer remote and autonomous operation. With the previous requirements in mind, the authors have proposed and validated a new electrohydraulic steering technology that offers energy efficiency improvement, increased productivity, enhanced safety, and adaptability to operating conditions. In this paper, the authors investigate the new steering technology's capacity to support remote operation and demonstrate it on a compact wheel loader, which can be remotely controlled without an operator present behind the steering wheel. This result establishes the new steer-by-wire technology's capability to enable full autonomous operation as well.