Dynamics modeling and robotic-assist, leader-follower control of tractor convoys. (February 2018)

• Record Type: Journal Article
• Authors: Cook, Joshua T.; Ray, Laura E.; Lever, James H.
• Is Part Of: Journal of terramechanics. Volume 75(2018)
• Page Start: 57
• Page End: 72
• Publication Date: 2018-02
• Subjects: Multi-body dynamics -- Tracked vehicle -- Leader-follower control; Trafficability -- Periodicals; Praticabilité (Routes) -- Périodiques; Trafficability; Periodicals; 629.222
• DOI: 10.1016/j.jterra.2017.05.002
• Languages: English
• ISSNs: 0022-4898

Abstract

Highlights: A physically motivated multi-body, tracked vehicle model is developed. This model incorporates payload, terrain, and power-train effects. A manned leader, robotic follower flexible formation strategy is proposed. The control law for the robotic follower rejects manned leader driving errors. This rejection ensures payload stability. Abstract: This paper proposes a generalized dynamics model and a leader-follower control architecture for skid-steered tracked vehicles towing polar sleds. The model couples existing formulations in the literature for the powertrain components with the vehicle-terrain interaction to capture the salient features of terrain trafficability and predict the vehicles response. This coupling is essential for making realistic predictions of the vehicles traversing capabilities due to the power-load relationship at the engine output. The objective of the model is to capture adequate fidelity of the powertrain and off-road vehicle dynamics while minimizing the computational cost for model based design of leader-follower control algorithms. The leader-follower control architecture presented proposes maintaining a flexible formation by using a look-ahead technique along with a way point following strategy. Results simulate one leader-follower tractor pair where the leader is forced to take an abrupt turn and experiences large oscillations of its drawbar arm indicating potential payload instability. However, the follower tractor maintains the flexible formation but keeps its payload stable. This highlights the robustness of the proposed approach where the follower vehicle can reject errors in human leader driving.