Abstract:
Vision is our most powerful sense. It provides us remarkable amount of information
about our surrounding and enables us to interact intelligently with the environment,
all without direct physical contact. Vision is also our most complicated
sense. The knowledge we have accumulated about how biological vision systems
operate is still fragmentary. Nature has proven to be capable of creating versatile
and flexible vision systems, which are much more efficient than all artificial vision
systems already designed. Therefore, the comprehension of some of the biological
principles of vision has brought important ideas and concepts for the development
of computational vision.
One of the main goals of the research is to develop a high-performance stereo
active vision head ,that can be used for studying human vision. The head consists
of two eye modules and a neck module on which the two eyes are mounted. The
camera platform has a total number of seven degrees of freedom, three in its neck
and two in its each eye. Stepper motors with custom built gear wheels are used to
drive all the degrees of freedom and the motors are used in a closed loop control
system with sequential optical encoders for providing position feedback.
This research also focuses on implementing an FPGA (Field Programmable
Gate Array) based microprocessor that interprets the instructions given by the
user, calculates all the necessary parameters for driving the motors as required
and controls the motors accordingly. This stand alone processor includes several
floating-point units operating in parallel with the other motor control units. A
total no of five floating point operations can be done in parallel that consists of
4 addition( or subtraction) and one multiplication( or division)operations. In addition,
a CORDIC processor also runs in parallel to calculate trigonometric functions
and root squares. With altogether the processor gives grater improvement to the
performance in terms of speed exploiting parallelism.
The results show that the FPGA based microprocessor for controlling the multi
degree of freedom stereo vision head is very efficient for active vision.
