Vehicle dynamics model of articulated trailer vehicles and their yaw stability states
What is an articulated vehicle ? It normally looks like the figure below. It has a pivot joint that allows it to turn sharply. Articulation is particularly helpful in case of longer vehicles as it helps with the turn but it also poses its own challenges. Handling Behavior of an articulated vehicle is more complex and unpredictable than a non articulated vehicle. That poses greater risk for the drivers who are not aware of the dynamic complexities. Moreover, you can add as many articulations as you want but in this article, I am only going to discuss modeling and stability…
List of my favourite Stand-up Comics, their styles and why I like them
Growing up during the 90s in India, I was always interested in comedy. I would try to watch all the comedy shows that are there on Indian TV during those times. Those days, stand up wasn’t that popular in India — very few people were doing it and even they would also be used as a filler “item” or as an opening act for a popular singers/bands etc. Comedy art form in India was mainly restricted to mimicry, parodies, funny poetry (which has a long rich tradition in India). There were not many western channels being televised and internet was…
Lane Detection using Gradient, Colour Thresholding and sliding window algorithm
In my earlier post, I talked about finding lane lines using Edge Detection and Hough Transforms. While Canny edge detection is great in finding the edges, it gives you a lot of edges in the picture, all of which are not relevant for the lane finding.
In this post, I would describe how to create a pipeline to find lane markings from a video using better algorithms than the last post. The pipeline would mark the lane, project the marked lane onto the video, tell the curvature of the road and also the position of the vehicle within that lane…
Lane Detection using Edge Detection and Hough Transform
How does coding a Lane finding system in an active video feed sounds? It seemed ubercool to me when I did this project with Udacity back in 2017. At that point, the aim was just to know enough basics and code a system somehow to get to the end result to have a feel of the power of computer vision even if you do not understand the exact details of behind the scenes. However, the main aim of this post is to explain image processing techniques. It is more about the journey than the destination.You …
Lane keeping is the one of the most basic and easy task done by the driver. It could be as simple as keeping the steering wheel steady on a straight road but even there, due to the external disturbances, the vehicle tends to drift from the lane. The naturalistic driving data can show that even if the road is perfectly straight, after some time interval the driver has to apply corrections to keep the lane. These time intervals to corrections are usually very small which means that driver has to constantly control the steering even on the straight road. …
Lateral dynamics
For the control of lateral motion of the vehicle, it is critical to model the lateral dynamics. Lateral motion control is used in various ADAS features like lane centering, lane keeping etc. The lateral dynamics models are also imperative in modeling vehicle behaviours during the lateral manoeuvres and can be used to study and design the system and components.
In order to calculate accelerations and velocities in different directions of interest, it is necessary to define the axis systems. Generally axis system can be Earth fixed or Vehicle fixed.
Earth Axis System
Earth fixed axis system has X,Y (horizontal) and…
My introduction to Computer Vision happened in 2017 when I was doing Self-driving Car Nanodegree from Udacity. The first semester was mainly related to Computer Vision and Deep Learning which sparked my interest in the subject. This post would cover some basic introduction of Computer Vision as well as Camera Calibration and affine transformations.
The goal of computer vision is to aid machines to see and understand the content of digital images. It deals with perceiving and understanding the world around you through images. Each digital image is made up of different pixels which are the smallest building blocks for…
This could be treated as part 2 of the spring rates post.
When the vehicle goes through the corner, it experience the roll motion when the roll center of the vehicle doesn’t coincide with the vehicle center of mass(which usually is the case). Vehicle roll motion affects the wheel loading which in turn affects the available tire lateral/longitudinal forces and hence the performance of the vehicle.
This body roll during the corner is opposed by a roll stiffness. Roll stiffness can be defined as the roll resisting moment of the body (sprung mass) about the roll axis. …
Active Chassis Systems
In a conventional vehicle, the driver controls the trajectory of the vehicle by performing functions like steering, acceleration and braking. These actions generate necessary tire traction forces and moments at the tire road interaction to modify the path of the vehicle.
However what if there is a system where these tire traction forces/moments can be controlled independently. Active Chassis Systems use actuators to modify individual tire traction forces which can bring a lot of opportunities as well as challenges.It increases the degree of mobility. If the rear wheels were allowed to steer, parking maneuvers would be enhanced…
Ride rate refers to the rate of change of tire normal force with vertical body movement and roll rate refers to the rate of change of tire normal force with body roll about its roll axis. The ride and roll rates of the car affect the wheel loading wrt the body position change. And the wheel load or tire normal force determines the available tire lateral/longitudinal forces which directly impacts the vehicle performance.
Individual suspension components like springs and antiroll bar affect the vehicle ride and roll. The ride performance of the car is many a times in conflict with…
Archit Rastogi
Vehicle Dynamics | Self Driving Cars | Comedy https://www.linkedin.com/in/archit-rastogi-2604/
