The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 10, 2008
Filed:
Jan. 09, 2006
Arun Kumar Seksaria, Cedar Falls, IA (US);
Mervin Peter Kizlyk, Cedar Falls, IA (US);
Robert Eugene Kasten, Denver, CO (US);
Arun Kumar Seksaria, Cedar Falls, IA (US);
Mervin Peter Kizlyk, Cedar Falls, IA (US);
Robert Eugene Kasten, Denver, CO (US);
Deere & Company, Moline, IL (US);
Abstract
A method of controlling a vehicle drive system is provided for a vehicle having an internal combustion engine, free-wheeling steerable front wheels, driven rear wheels, an infinitely variable transmission (IVT) transmitting torque from the engine to the rear wheels, and a control unit for controlling the IVT as a function of sensed parameters and supplying a speed command to the IVT for commanding a speed of the rear wheels. The method includes sensing a steering angle of the front wheels, sensing a front wheel speed, sensing a rear wheel speed, generating a corrected estimated vehicle speed as a function of the front wheel speed and the sensed steering angle, and increasing the speed command in response to a comparison between the corrected estimated vehicle speed and the rear wheel speed. The infinitely variable transmission is preferably embodied by a hybrid electric drive system. The estimated vehicle speed value is determined as a function of a gear ratio of a rear wheel drive, the front wheel speed, a rolling radius of the front wheel, a rolling radius of the rear wheel, and the steering angle of the steerable front wheels. The speed command is increased when the rear wheel speed is less than 90% of the corrected estimated vehicle speed.