If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
ESL 04-10: Simulation of Vehicle Longitudinal Dynamics
Greetings,
I'm reading "ESL 04-10: Simulation of Vehicle Longitudinal Dynamics" in an attempt to write a car simulations engine. However I came across several dilemmas and was hoping to find answers here - In page 3 an equation (04/01/C) of the form: V = (-Fxt + g*sin(theta) - Fd(V)) / m Was supposed to give the velocity of the car as the net force divided by mass. However, IIRC such a formula would give the acceleration not the velocity (A similar equation was given in page 6 for the angular velocity) - Another equation (04/01/D): Fz = mg {(C/L)cos(theta) + (H/L)sin(theta)} - mV (H/L) Is supposed to give the normal force on the front wheels. Which is a variable controlling the total force (Fxt) in the first equation (04/01/C). Now suppose that theta is 0 which means that the fist term would evaluate to zero, and suppose that the car is starting with zero velocity which means that the second term is also zero. And Fz is zero as a whole, hence Fxt is also zero (No force is acting on the vehicle body). Since Fxt is zero this would mean that V is also zero (from the first equation). And we are faced with a paradox: The car won't move until a force is applied to it, but no force will be applied until the car moves. I suppose that in real life clutching/declutching the engine will solve this problem, however how can I solve such a problem in a simulation? PS: Article link: www.le.ac.uk/eg/embedded/pdf/ESL04-01.pdf Thank you for your time Abdo Haji-Ali Programmer In|Framez |
Ads |
#2
|
|||
|
|||
ESL 04-10: Simulation of Vehicle Longitudinal Dynamics
You just made my head 'Splode.
-Larry "Abdo Haji-Ali" > wrote in message ups.com... > Greetings, > > I'm reading "ESL 04-10: Simulation of Vehicle Longitudinal Dynamics" in > an attempt to write a car simulations engine. However I came across > several dilemmas and was hoping to find answers here > > - In page 3 an equation (04/01/C) of the form: V = (-Fxt + > g*sin(theta) - Fd(V)) / m > Was supposed to give the velocity of the car as the net force divided > by mass. However, IIRC such a formula would give the acceleration not > the velocity (A similar equation was given in page 6 for the angular > velocity) > - Another equation (04/01/D): > Fz = mg {(C/L)cos(theta) + (H/L)sin(theta)} - mV (H/L) > Is supposed to give the normal force on the front wheels. Which is a > variable controlling the total force (Fxt) in the first equation > (04/01/C). Now suppose that theta is 0 which means that the fist term > would evaluate to zero, and suppose that the car is starting with zero > velocity which means that the second term is also zero. And Fz is zero > as a whole, hence Fxt is also zero (No force is acting on the vehicle > body). Since Fxt is zero this would mean that V is also zero (from the > first equation). And we are faced with a paradox: The car won't move > until a force is applied to it, but no force will be applied until the > car moves. I suppose that in real life clutching/declutching the engine > will solve this problem, however how can I solve such a problem in a > simulation? > > PS: Article link: www.le.ac.uk/eg/embedded/pdf/ESL04-01.pdf > > Thank you for your time > Abdo Haji-Ali > Programmer > In|Framez > |
#3
|
|||
|
|||
ESL 04-10: Simulation of Vehicle Longitudinal Dynamics
Abdo Haji-Ali wrote: > Greetings, > > I'm reading "ESL 04-10: Simulation of Vehicle Longitudinal Dynamics" Don't spoil the ending for the rest of us.... |
#4
|
|||
|
|||
ESL 04-10: Simulation of Vehicle Longitudinal Dynamics
"Abdo Haji-Ali" wrote:
> I'm reading "ESL 04-10: Simulation of Vehicle Longitudinal Dynamics" in > an attempt to write a car simulations engine. However I came across > several dilemmas and was hoping to find answers here http://groups.google.com/groups?as_q...s.simula tors Happy reading! j |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Check This Out: Electric Vehicle Production | [email protected] | Honda | 0 | July 30th 06 03:15 PM |
Check this out: electric vehicle production http://groups.google.ca/group/electricvehicle | [email protected] | Technology | 0 | July 30th 06 02:51 PM |
Women Busted for DUI For Pushing Car | Dave | Driving | 309 | August 7th 05 06:01 PM |
ok i'm buying a 2001 GT convertable | Defiant | Ford Mustang | 5 | May 21st 05 03:31 PM |
New *FREE* Corvette Discussion Forum | JLA ENTERPRISES TECHNOLOGIES INTEGRATION | Corvette | 12 | November 30th 04 06:36 PM |