Implementation of Barrier Sensing and Avoidance System on FPGA for a Wheeled Robot

Abstract

Aims: This paper is to describe the process of spotting a barrier on the path of a wheeled robot and finding an alternate way to keep away from it. Method: For path, planning, image-processing technique is used and for this barrier-sensing and avoidance system, ultrasonic sensor is used. FPGA board processes the sensor output and after processing, it gives instruction to the motor arrangement to control the speed and direction of the wheeled robot. Results: We took one digital storage oscilloscope to collect all the data from sensor board. Although the color and lumen of the reflection matters a lot in the reading, so a variety of different objects we have selected to reduce the probability of error. A Very High Speed Integrated Circuit (VHSIC) Hardware Description Language (VHDL) block we generate for control algorithm and connect to the enable pin. Fig-8 shows the calculation block and fig-9 shows the ADC. As the FPGA board reads digital signal, hence the received signal we converted to digital with the help of an ADC of type NS ADC128S022. It is a 12-bit converter. Initially a bigger particle we kept in front of the sensor to understand and quantify the highest scope of it. DSO we used to view the response of both pulse and the analog signal. The code, which we have written for the operation of the ultrasonic sensor, has used a high logic of 10 µs width for triggering input. Program is measuring the object distance by calculating the logic high time of the ECHO pin that we have programmed as input. For servo operation, a pulse we used with 1.5ms on time and 20-millisecond time-period. To change the rotating angle different on time we have adopted. Conclusion: Wheeled robots have a no of applications. Depending on what sensor people use or what actuators or microprocessors they apply, the response time differs from one model to the other. To use it in real time applications a robot should give very fast response. In realistic approach FPGA development board is widely used in robot models recently because of its very fast response time, flexible system approach, quick generation of signals, parallel processing ability and obviously cost is pretty less when compared to other processor. References, figures, tables, chemical structures etc.