Correlation detector based on a FPGA for ultrasonic sensors

2010

This paper presents an FPGA-based ultrasonic location system. This system uses low-cost FPGAs and ultrasonic transducers to provide 3-D location to mobile nodes in an indoor environment. Synchronization is reached using the radiofrequency transducers that mobile nodes usually include. FPGAs have been used to sample ultrasonics and radiofrequency inside a custom peripheral which is attached to a MicroBlaze soft-processor. The

Proceedings of 1995 IEEE International Conference on Robotics and Automation, 1995

In this paper an ultrasonic multisensor acquisition and processing system with up to 32 air-ultrasound transducers in the frequency range of 40-200 kHz is presented. The system was developed f o r an obstacle avoidance applications in the robotics field. Both the acquisition and processing capability of the apparatus (it is based on the Digital Signal Processor TMS32OC2.7 and can sample up to five parallel channels) allows to perform tasks of different difficulty degree, l q i n g between the target-ranging and the pattem recognition. As an example of application, a neural approach to a typicalproblem in the robotic navigation field is presented, that highlights the system-flexibility features.

Microprocessors and …, 2003

Multi-mode techniques reduce scanning times in ultrasonic systems, as they allow transducers in a sensor to simultaneously emit and receive without interference. In order to implement these techniques, it is necessary to encode each transducer's emission. The use of orthogonal pairs of Golay sequences associated with different emitters avoids crosstalk among them. However, these sequences imply an increase in the computational complexity required in the receiver. This paper presents the practical implementation of a system, with two emitters and four receivers, using a low-cost hardware architecture based on a FPGA. The ultrasonic signal processing is performed in real time. q

IEEE Transactions on Instrumentation and Measurement, 2000

This paper presents a system to classify and locate basic ultrasonic reflectors (plane, corner, and edge) in 3-D environments. The classification system is based on the principalcomponent-analysis (PCA) technique, using the time of flight (TOF) as the classification parameter. The system proposes a sensorial structure to simultaneously obtain up to 16 TOFs at every emission/scanning process. A particular and different macrosequence has been assigned to every transducer in the sensorial system to encode their emissions. These macrosequences, obtained from complementary sets of sequences, allow simultaneous emission and reception to be carried out with all the transducers for the same scanned environment. The set of obtained TOFs make it possible to identify the type of ultrasonic reflector, as well as its position in 3-D environments. The results achieved by the classification system are presented for both simulated and real data.

Feasibility study of an ultrasonic ranging system able to detect obstacles in a robotic environment. The localization of the obstacle is computed by correlations between the emitted signal and the echos at three receivers. The emitted signal is configurated in such a shape that the results are robust against the Doppler effect, occuritig when the obstacle is mobile relatively to the robot. The data processing, performed digitally, is conducted iji order tu make the computation time as low as possible. Experimentation on prototype has confirmed theoretical precisions of a few millimeters on distance and a few degrees on azimuth and elevation.

American Journal of Modern Physics, 2022

There are several ways of contactless distance measurements. This research work made use of the principle of ultrasonic distance measurements and calculations as well as tracking of dynamic object by the techniques of distance comparison. When an electrical pulse of high voltage is applied to the ultrasonic transducer it vibrates across a specific spectrum of frequencies and generates a burst of sound waves. Each time any obstacle comes ahead of the ultrasonic sensor, the sound waves will reflect in the form of echo and generates an electric pulse. The time taken between sending sound waves and receiving the echo was calculated and the patterns of echo were compared with the patterns of sound waves to determine the detected signals condition. The device consists of two HC-SR04 ultrasonic sensors that sweep continuously through 1800 to detect and track object based on developed and installed codes in the Arduino Uno microcontroller and displays the range and angular position using Processing 3 Software on a computer screen display. The envisaged minimum and maximum range of object detections is 2cm and 39cm respectively using processed signal. However, the measured distance is from 5cm to 35cm and the corresponding calculated distances using waveforms from an oscilloscope were 6.8cm and 47.6cm. The discrepancies were attributable to the 0.2ms rise time of the trigger signals. The device was capable of tracking only relatively slow-moving objects and can be applicable in robotic vision, automatic guided vehicles, security surveillance, automobile anticollision system and precision contactless measurements.

Proceedings of the 15th IFAC World Congress, 2002, 2002

The application of multi-mode techniques, in order to determine the times of flight of the ultrasounds, gives solution to the main problems of this kind of sensorial system (little precision and low speed of acquisition), but also presents certain constraints to perform its processing in real time. In this way, the application of the principles of the logical reconfiguration implies more optimal and efficient systems in the use of resources assigned initially to each task of the process, obtaining significant improvements in the developed platforms compared with other possible processing architectures more frequently used.

Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems

This paper deals with the development of a strategy for fast multi-object identification which utilizes a time-of-flight(T0F) based ultrasonic linear array consisting of commercially available inexpensive ultrasonic transducers. By applying computer controlled delayed pulses to the transducers, the linear array system can perform beam steering through a scan range of 0" +60" in a programable scan angle steps. The system has a beam scan capability

2009

This work has been partially supported by the CCG08-UAM/TIC-4258 project of the Comunidad de Madrid and UAM.