The wheel loader is modeled as a mechanical manipulator with four degrees of freedom (DOFs), which comprises a seven-bar linkage using the symbolic notation of Denavit and Hartenberg. Homogeneous transformation matrices are used to capture the spatial configuration between adjacent links. The forward kinematics method is used to formulate the kinematics equations by attaching Cartesian coordina...

In this paper the potential of predictive control in a hybrid wheel loader is estimated using related research results as a basis. The application of hybrid technology to a wheel loader application is discussed and differences between on-road vehicles and wheel loaders are clarified. The main part of the related research has its focus on on-road vehicles where the usage patterns are more cohere...

A nonlinear wheel loader model with nine states and four control inputs is utilized to study the fuel and time efficient optimal control of wheel loader operation in the short loading cycle. The wheel loader model consists of lifting, steering and powertrain subsystems where the nonlinearity originates from the torque converter in the drivetrain. The short loading cycle, from loading point to a...

For the case with repetitive driving cycles for a wheel loader the driving cycles parameters affects on the optimal control of the wheel loader is studied. It is clearly seen that average efficiency is not enough and also incorporating driving cycles parameter such as average power, maximum power and amount of recuperative energy will lead to an better estimate on the fuel equivalence factor W .

Information about wheel loader usage can be used in several ways to optimize customer adaption. First, optimizing the configuration and component sizing of a wheel loader to customer needs can lead to a significant improvement in e.g. fuel efficiency and cost. Second, relevant driving cycles to be used in the development of wheel loaders can be extracted from usage data. Third, online usage ide...

Articulated wheel loaders used in the construction industry are heavy vehicles and have poor stability and a high rate of accidents because of the unpredictable changes of their body posture, mass and centroid position in complex operation environments. This paper presents a novel distributed multi-sensor system for real-time attitude estimation and stability measurement of articulated wheel lo...

When wheel loaders move with velocity higher than 10 km/h, they are subject to intense longitudinal vibrations. These vibrations are experienced particularly unpleasantly by an operator. Passive vibration stabilisers are used for controlling their intensity. They make outrigger’s support more flexible so that outrigger’s vibrations counteract the wheel loader’s longitudinal oscillations when mo...

Optimizing the configuration of a wheel loader to customer needs can lead to a significant increase in efficiency with respect to fuel economy, cost, component dimensioning etc. Experience show that even modest customer adaptation can save around 20% of fuel cost. A key motivator for this work is that wheel loader manufacturers in general does not have full information about customer usage of t...

Optimal control of a wheel loader operating in the short loading cycle is studied in order to investigate the potentials for fuel consumption reduction while maintaining acceptable production rates. The wheel loader is modeled as a system with five states and three control inputs including torque converter nonlinearities. The torque converter is modeled with no lockup enabling power transmissio...

The authors have been conducting development of an autonomous loading system by wheel loader. As a part of the development, a detection method of location of the dump truck will be described in this paper. In the process of loading to the truck in the operation, the loader approaches to the dump truck in very close distance. The function for collision avoidance between the loader and the truck ...