Abstract: A platoon of electric pallets (e-pallets) includes a follower e-pallet connected to or in wireless communication with a leader e-pallet. The platoon also includes a sensor suite, road wheels, an electric powertrain system, and a local controller. The sensor suite includes a velocity sensor configured to measure a velocity of the follower e-pallet, an angle sensor configured to measure an azimuth angle between the follower and leader e-pallets, and a length or distance sensor configured to measure a distance therebetween. The local controller executes a method to adaptively move a variable target point (VTP) on the leader pallet in response to the velocity, the azimuth angle, and the length, and to thereafter control a dynamic output state of the electric powertrain system using the VTP.

Abstract: An electronic pallet (e-pallet) includes a superstructure mounted to a wheeled base platform. A tether device defines an articulation angle with respect to a leading edge of the superstructure, and is grasped by an operator towing the e-pallet. A motor connected to driven road wheels transmits a drive torque to the road wheels responsive to motor control signals, including a desired yaw rate and ground speed. A speed sensor, angle sensor, and length sensor are respectively configured to determine an actual ground speed of the e-pallet, the articulation angle, and a length of the tether device. An electronic controller, in response to the input signals, generates the motor control signals using proportional-integral-derivative (PID) control logic. Coupled lateral and longitudinal dynamics control loops respectively determine the desired yaw rate and ground speed to accommodate for motion of the operator.

Abstract: A method of controlling tethered self-propelled platforms is provided. The method comprises providing a platform leader and a platform follower connected to the leader with a tether to define a first heading line of the leader and a first coordinate frame of the follower. Each of the leader and the follower is pivotally moveable relative to the tether, defining a leader angle and a follower angle. The method further comprises estimating a predicted position of the leader based on a current position, a current speed, and a current yaw rate of the leader. The predicted position of the leader defines a predicted heading line of the leader. The method further comprises determining a trajectory of the follower from the first coordinate frame to the predicted heading line defining a second coordinate frame of the follower. The trajectory is based on a desired distance the predicted heading line and a desired change in yaw angle of the follower.