A mobile autonomous agricultural system

There is disclosed a mobile autonomous agricultural system comprising a powered mobile unit, two distance sensors, an attitude sensor, a path determination module and 5 a controller. The powered mobile unit extends from a front end to a back end along a longitudinal axis, and is configured for carrying agricultural equipment and to move along rows of posts along the longitudinal axis. The powered mobile unit comprises a chassis supported by wheel units, each wheel unit comprising a wheel with a suspension assembly. The suspension assembly comprises a suspension unit 10 comprising passive spring around a shock absorber coupled to the wheel, and a linear actuator configured to move the suspension unit relative to the chassis of the mobile unit to thereby move the wheel relative to the chassis independently of the suspension unit. The two distance sensors are disposed on the powered mobile unit, and each configured to sense external objects within two dimensions and the distance of the 15 external objects from the respective distance sensors in opposing front and back directions along the longitudinal axis. The attitude sensor is configured to determine the attitude of the powered mobile unit with respect to the horizontal. The path determination module is configured to: receive distance signals from the distance sensors, identify a row of posts based on the distance signals; and generate a motion 20 trajectory, based on the identified row of posts, for the powered mobile unit to follow. The controller is configured to control the linear extension of the linear actuator of the suspension assembly and the direction of travel of the mobile unit based on the motion trajectory of the path determination module and an output of the attitude sensor, to follow the row of posts and to maintain a horizontal attitude of the powered mobile unit 25 whilst maintaining contact of the wheels with the ground. Accompanied by Figure 1 -22 50 18 60 -'u '18 Figure 1