One of the most frequent questions asked about Leddar through interactions at conferences or business meetings with prospective customers is “Ok, I get what you can do, but what exactly makes Leddar better than other optical time-of-flight sensing methods?”
A very relevant question indeed.
This post aims to shed some light on this very common interrogation.
Fundamentally, the “secret sauce” of Leddar lies not as much in the discrete component combinations and other hardware design considerations, as important as they may be in providing the right set of specifications needed by your application. Rather, it’s the highly optimized data acquisition process and superior signal processing capabilities at the core of the sensor that make it better than all other alternatives.
Contrary to other methods which rely primarily on the time span between the transmission and reception of a signal to estimate the distance of an object, a Leddar-based sensor will transmit thousands of light pulses per second, capture the received echoes, convert them into a digital form and process the data accumulated through proprietary algorithms to provide a precise measurement. Advanced signal processing also enables the measurement of multiple objects simultaneously.
Let’s add more meat to the bone and look more deeply into the key ingredients of Leddar’s secret sauce, the three main advantages that make the Leddar technology unique.
Advantage 1- High Sensitivity
The superior sensitivity of Leddar’s patented signal processing enables the detection of objects reflecting a very weak light signal, and provides superior range-to-power ratio for consistent performance over both short and long range.
The following graph provides a representation of how the rapid, successive signal accumulation makes the digitized signal evolve into a much cleaner shape, allowing for superior object detection.
For each pulse, the return signal is acquired and the signal from successive pulses are accumulated (sum operation), which increases the signal to noise ratio. A simple way to see the effect of this operation is that any random signal (noise) will be averaged out. This process improves the sensitivity and maximizes the range that can be obtained for a given amount of output power. This advantage can be used to obtain a higher range or to use lower power emitters.
Advantage 2- Powerful signal processing
Unlike other sensors that may provide only raw data or simple readings, Leddar powerful algorithms are embedded into the core of each Leddar sensor. This unique signal processing power allows for the rapid delivery of accurate measurement, and also provides the sensor with superior lateral target discrimination and the capability to detect of multiple objects simultaneously within the sensor’s field of view.
Advantage 3- Immunity to noise and lighting conditions
The high sensitivity and signal processing capabilities enable the use of diffuse light beams (such as LEDs). This ensures that a large portion of the emitted light will reach the targets in the field of view, allowing for object illumination and detection even in challenging environments. A Leddar sensor thus provides immunity to noise caused by environmental conditions such as rain, snow, fog or dust.
Through signal accumulation, the successive pulses and random nature of the particles obstructing the target will result in the filtering-out of the “noise” caused by those environmental conditions and hence provide highly reliable detection and ranging even in harsh environmental and in low visibility conditions. Also, unlike other optical detection technologies, Leddar detection performance remains unaffected by variations in ambient light, for flawless detection.
It all starts at the core
Each Leddar-based sensor is much more than an assembly of various electronic components: it is the result of a decade of R&D focused on providing unique, highly efficient detection and ranging capabilities based on light. And you can find this “secret sauce” implemented right at its core.