Degree Type


Date of Award


Degree Name

Doctor of Philosophy


Agricultural and Biosystems Engineering


An investigation was conducted to determine the feasibility of automatic controls to automate feed distribution in feedlots. The control approach was restricted to compatibility with conventional feeding equipment. Input control signals were taken to originate from commonly available mechanical and electronic sensors. The control system was implemented with standard digital logic components;The proposed digital control system is based on a railguided, self-propelled automatic vehicle capable of delivering feed sequentially to 255 pens located on both sides of a single feeding path. A manual, closed-loop control system consisting of the following functions was developed: (1) pen identification, (2) initialization control, (3) feeding mode, (4) exit from feeding mode, (5) re-entry into feeding mode, (6) end of feeding cycle, (7) ground drive and conveyor control, (8) interface and auto/manual mode, (9) monitoring of automated system and (10) data and failure display and alarm. The control system allows either automatic or manual operation of the feeding vehicle. Digital electronic circuits capable of implementing the desired control functions were designed;The feeding cycle is manually initiated and automatically terminated when feed has been delivered to all pens requiring feed. It can be partially programmed to enable feed delivery to sections of the feedlot. Two feed rations can be delivered. The feeding status of each pen is recorded. The pen feed rations are stored in reprogrammable memories;The operation of the automated feeding system is based on the automatic identification of the feedlot pens. The number assigned to a pen is coded, using binary pulse-code modulation. Frequency-shift keying is used to transmit the coded number. The received coded number is recovered by specialized communication circuits and then validated;The control system monitors the vehicle components and the major electronic circuits to detect failures, prevent damage and produce a safe operation. Furthermore, it incorporates safety sensors and logic circuitry to meet the basic safety requirements pertaining to automated vehicles;The proposed automated feed distribution system for feedlots is expected to: (1) reduce management requirements through automatic distribution of feed to cattle raised in pens, (2) increase efficiency of feeding operation by eliminating time losses associated with secondary feed transfer, (3) eliminate damage to feedbunks through positive guidance of the vehicle by rails, and (4) save energy by eliminating secondary feed transfer.



Digital Repository @ Iowa State University,

Copyright Owner

Regis Joseph Boily



Proquest ID


File Format


File Size

320 pages