# car

1. ### I Modeling torque on a half car model

Imagine an half car model with the two suspension and two wheels. There is a torque applied to the rear wheels, that torque create the force between tire/asphalt that pull the car. How that torque react in the main body? I have two hypotesis: 1) It's only internal force that tend to bend the...
2. ### Car reading 17V+ in the battery when running, how to fix?

Hi, I have a 2004 Toyota Matrix with 270 000km. It's working great but today when i started my car the battery was going up to 17.2V (i have a battery voltage reader in the car at all time). It's the first time it went up there, it usually stays in the 13-14V. I know something is wrong and I...
3. ### Question about multimeter continuity

Hi guys , i am working in the automotive industry today i encountered a weird electrical issue and i am sure you guys have an explanation , i was using my multimeter to check continuity between different stuff , by mistake i put the leads on the car battery terminals i found the multimeter...
4. ### I How to calculate each car tyre load during cornering?

This is about vehicle physics. I know how to calculate weight on each axle on a car during deceleration. Given the picture below: The weight on the front axle is calculated as: Wf=(c/L)*W-(h/L)*M*a and the weight on the rear axle is calculated as: Wr=(b/L)*W+(h/L)*M*a where c and b are the...
5. ### How to produce a harmless gas in seconds? (for an emergency car floatation device)

I need to make the design of car floatation devices. In my case, the airbag/raft is for floating the car in case of floods. I am considering to use Sodium Azide, just like in car airbags, but it inflates very fast and shrinks in a short time. Is there any other chemical reaction that can produce...
6. ### A few questions on car mechanisms and driving habits

I have a Toyota Etios Liva, about three and a half years old. It is a petrol variant, with manual transmission. I am quite interested in the mechanisms of a car and good driving habits. Sadly, none in my family knows driving. My knowledge of driving habits extend to the manual given with the car...
7. ### Automotive Hydrogen Car Fuel Tank

How do hydrogen powered cars prevent the permeation of hydrogen through the valve used to fill the car's tank with hydrogen? Is a regular check valve used or is the valve special in some way?
8. ### How to use my data of Ixx, Iyy and Izz?

Hi everyone, thank you for reading my thread I know the question is weird but I can't seem to explain it otherwise. My problem: Basically I am finishing a final year project which I based on a Formula Student Vehicle. Using CAD I have the vehicle modelled, and through the model analysis and...
9. ### Car's braking distance formula

Hello everyone ! I'm working on my highway code and my book give me the approximate formula and the real formula of the braking distance. Here's the real formula according to the book : $$Bd = \frac{V^2}{254 \times f}$$ With : V : the velocity f : the adherence coefficient. But I have on...
10. ### Can you damage your starter motor with too much current?

Hey all! Today I took my car to the shop for some starter issues. They told me that the starter had been damaged by a battery with a higher CCA rating than was safe for the starter motor and it burned out my motor slowly over time. I feel like they may be BS'ing me, but I'm not sure. I know my...
11. ### B Relation between centrifugal force and speed

Does centrifugal force generate in increase in overall speed? For example, if I am driving down a highway on-ramp which goes in a circular fashion, with my speed slowly increasing, does my overall speed increase because of the centrifugal force generated from the circular on-ramp? Is more force...
12. ### Accelerating a car including the moment of inertia of the wheels

1. Homework Statement A car accelerates from rest on a horizontal surface. The engine provides a torque of τ = 200 Nm on each of the two front wheels. Each of the four wheels on the car weigh m = 15 kg, have radius R = 0.35 m and can be considered solid, uniform discs. The rest of the car (not...
13. Y

### Automotive Construction of CVT Metal push belt

I am trying to understand the construction of CVT Metal belts that are made up of steel elements and some rings. I do not understand the full construction details of the belt. The most detailed information I have got ever is in this PDF on page 5...
14. M

### Questions involving airflow and pressure around a car

1. Homework Statement 1.Since the roadster seats only two people, it has only two side windows--one on each side. Each window is aligned squarely on the vehicle, so air can flow straight past the window as the vehicle heads forward. However, the air flowing around the roadster's windshield has...
15. H

### Why do we need a switch before a relay?

So in high current circuits which involve say a starter motor in a car we need a starter relay since a normal switch cannot handle the high current flow. I think the reason I'm asking this question is because I don't understand what exactly makes the relay be able to handle the current unlike...
16. ### Automotive Flying Hypercars?

Recently the Bugatti Chiron set a record of some sort for rapidly accelerating to 249 mph and then dropping back down. The engine is something to the effect of 1500 horsepower and the vehicle isn't terribly heavy. Old Airplanes had engines below 400 horsepower and ultra lights can be far less...
17. S

### 4WD Arduino Controlled car - Problem with motor shield

I've been working with what will be a small Arduino 4WD controlled car, however now I've found a problem. The motor shield I used is an Arduino UNO motor shield R3, v3, which means that it can only control 2 motors, howerver I'll be using 4. Is there any way to use this same shild but apply all...
18. ### Speedometer working principle

I'm wondering how does speedometer work. To be specific lets talk about car speedometer. I googled it and found out that there are different kind of speedometers, but not quite understood it's working principle. My question is not about how it shows us speed (Mechanically with arrow or...
19. I

### Automotive Car downforce: accelerating air under the car vs blocking

As most of you know real racecars have flat bottoms, rear diffusers and in the front well... a variety. So to keep this simple. I am building a car with a flat bottom and rear diffuser, car raked at 4 deg, diffuser at 14 (all details will be adjusted based on learned info) and nothing on top or...
20. ### Automotive Friction force, Coefficient of friction &Traction

I have few (more or less) general questions: 1. I know that: "The coefficients of friction are nearly independent of the area of contact between the surfaces". I understand this, but I know from everyday life, when car tire tread is worn off, braking distance increases and maximum acceleration...
21. ### Simple and clear LED question. LEDs pop and break

Attached is a picture of my set-up. It is very simple and if for a car (12V) The LED kit comes with 3 options: Hard wire install, cigarette lighter install, and 9 + 9 V battery demo. The peculiar thing is when I connect the hard wire install plug (shown at the top of the picture) to a...
22. ### Question about friction? Dynamics

1. Homework Statement This is the problem http://imgur.com/a/1XFlt 2. Homework Equations This is the given FBD http://imgur.com/a/CURqA 3. The Attempt at a Solution Now the car should have a tendency to slip down the ramp thus causing the frictional force to oppose this motion. But the...
23. ### Automotive Traction and friction

Hi, I'm simulating the behavior of a car and I have some troubles with the tires. Specially with slip when the car is accelerating. I've seen many documents over the internet and I understood 2 main things: Wheel slip is necessary to accelerate & the coefficient of friction depends on the slip...
24. ### B Is the car accelerating?

As I was driving I was wondering if there is way to know if the other cars on the road accelerating. I think that if I were travelling at a constant, then if the rate at which the distance my car and another car was changing was not constant, then the other car would be accelerating. But is...
25. ### I Friction and turning angle relation

Hi there, Suppose we had a car going in a circle. We know that the turning angle(angle between the movement direction and the wheel axis) and the friction are connected, because friction determines the centripetal force and it determines the radius of the circle that we make with our car. I need...
26. ### Can a capacitor start a toy car?

Hi, I am trying to build a solar powered toy car. And no its not for my son, its for my own curiosity. The problem I am having is that...while the solar panel is sufficient to rapidly turn the (4) micromotors 6 inches away from a lightbulb it isn't sufficient to even turn the wheels when I put...
27. ### I Acellerating car vs constant speed car

Hi, I've been dsicussing this with som friends, and would be thankful if someone took the time to explain it to me :) The scenario: Car A travels at constant velocity (80km/h) along the road and hits a brick wall. Car B acellerates upward towards 100km/h, and at excactly the moment it passes...
28. ### Automotive Propeller powered car questions

I'm trying to build a propeller powered car. Right now I'm trying to find ways to make if faster because I'm limited to a 6 volt battery pack. I was wondering if I used a nozzle shaped design like they do for rockets if it will make it faster or slow it down. The propeller is 6 inches and I was...
29. ### Automotive Single actuator Wiper design to wipe a surface area

I'm given this problem to solve with the assumption as stated above. The answers need not be logical as long as the linkage mechanism can be simulated. I've attempted the question using Mercedes Mono Wiper mechanism but only manage to cover 41% given the width of the wiper. May I ask if there...
30. ### Automotive Formula 1 Traction Control tuning

Hello, I'm a mechanical engineering student and I'm working in traction control for Formula 1 cars. The traction control in the cars is simple, too simple: an engine cut is done when the engine is at a certain RPM and slip value. A matrix of four values of RPM and slip has to be provided to...