DIFFERENCE EQUATIONS - ADAPTIVE CONTROLLER DESIGN TECHNIQUE.
AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OHIO SCHOOL OF ENGINEERING
Pagination or Media Count:
An identification means for adaptive control systems is an average difference equation approximation for the vehicle transfer function. Solution of the difference equation, accomplished in the control computer of the adaptive system, determines which of several fixed compensators to use for existing flight conditions. The difference equation derived for the X-15 longitudinal dynamics is analyzed mathematically for various inputs. The X-15 pitch-rate loop and control computer is simulated on analog and digital computers. The difference equation solution error becomes large after two or three seconds. Exact difference equations for given flight conditions are generally more accurate. Significant errors still result after several seconds. Computer results indicated the difference equation solution was relatively accurate for not more than two or three seconds. Author
- Flight Control and Instrumentation
- Operations Research