Lecturers Flashcards
What is a signal? (BOLD)
A value that changes over time
What is a system? (BOLD)
A system can be defined as a connected set of elements which transforms an input signal into an output signal and they are usually modelled as dynamical systems, differential equations or difference equations.
Describe a measurement range?
Measurement range in robotics refers to the range of values that a sensor or actuator can detect or operate within. It is the minimum and maximum values that can be measured or controlled by the robot’s system.
For example, a distance sensor may have a measurement range of 0-100 cm, meaning it can measure distances within this range.
Describe a measurement resolution?
The measurement resolution is the smallest detectable change that can be measured.
For example, if a robot’s sensor has a measurement resolution of 1 millimeter (mm), it means that it can detect changes in distance of at least 1 mm. So if the sensor measures a distance of 10.5 mm, it could be that the actual distance is anywhere between 10 mm and 11 mm. However, if the sensor had a higher resolution of, say, 0.1 mm, it would be able to detect changes in distance of 0.1 mm, leading to more precise measurements.
Describe measurement error?
Super simple just what can go wrong when measuring stuff for example when measuring a table with measuring tape, the tape can shift, be a bit elastic, etc.
Another example is software that has to run in less than 5 seconds, you run the software and it takes less than 5 seconds, however, your boss runs the software as well and takes more than 5 seconds to run.
How do we work out the…
- Mean?
- Variance?
- Standard Deviation?
MEAN
The mean is worked out by getting the sum and dividing by the volume of numbers
nums = [6, 7, 8, 9, 10]
mean = sum(nums) / len(nums)
//the mean is 8
VARIANCE
https://www.youtube.com/watch?v=deIQeQzPK08
We get mean and then subtract each num by the mean after we square that number and get the sum of all nums. Finally, we divide that sum by length - 1.
foreach (nums as num):
sum += (num - mean)^2
//6 - 8 = -2
//-2 * -2 = 4
variance = sum / (len(nums) - 1)
//the variance is 2.5
STANDARD DEVIATION
We square root the variance
sqrt(variance)
//the standard deviation is 2.5 1.4
What is a outlier?
An outlier is an experimental data point not following the underlying distribution of points.
https://miro.medium.com/max/697/1*O3lOgPwuHP7Vfc1T6NDRrQ.png
Describe robotic sensor classifications? (Bold)
Proprioceptive: Measure internal robot variables, e.g, battery, motor temperature, etc.
Exteroceptive: Mesaure external variables, e.g, distance sensors, bumpers, cameras, etc.
Active: These sensor provide some effect in the environment to measure e.g, laster scanners, encoders, etc.
Passive: These sensors measure the effects that are available within the environment e.g, camera captures colors but the colors are present within the environment.
Sensor Error Resolution
Sensor error resolution in robotics refers to the minimum change in measurement that a sensor can detect accurately. It is the smallest change in the measured variable that can be detected by the sensor, without being affected by the noise or errors in the measurement.
For example, a distance sensor with an error resolution of 0.1 mm means that it can detect a change in distance of 0.1 mm with a high level of accuracy. If the change in distance is smaller than 0.1 mm, the sensor may not be able to detect it accurately and the measurement may be affected by noise or errors.
What is a state?
one or more variables
What is state transition law?
How the state changes over time
What is output?
The value of state
What is a plant?
A plant is just a system that has to be controlled, that means its output has to fulfil some criterion or reach some desired value. Usually the plant is given and we cannot modify it, we can only act on or modify its state through its inputs.
What is a set point?
The signal we want the systems output to be
What is a controller?
A controller is a designed system or function that takes the error signal defines as the difference between a reference input and the output of a plant to be controlled. The controller generates an action signal or control for the plant. The control signal generated by the controller should be such that it drives the output of the plant to the reference signal.
