Jason, I'm sorry for mailing again but I am not yet sure of the implementation - 'We need valid mathematical descriptions of a variety of common forces that will work nicely with our code generators for efficient numerical implementations'. I do not have a clear understanding of how force should be implemented as mentioned by you, could you please help me out here?
Thanks, Praneeth On Saturday, April 9, 2022 at 2:44:50 PM UTC+5:30 praneeth ratna wrote: > Jason, > > Thanks for the reply, > > I have started writing my proposal, But have some queries regarding the > implementation. > I have created a new submodule forces.py in sympy.mechanics module and > create force definitons in forces.py. I have included code for one of the > model here: > def linear_hooke_contact_model(stiffness, penetration): > stiffness = sm.sympify(stiffness) > penetration = sm.sympify(penetration) > force = stiffness * penetration > return [force] > > Is this the write way of creating the force models, or do we need to > create classes for individual force model? Please correct me here if I'm > wrong > > Thanks, > Praneeth > > On Wednesday, April 6, 2022 at 2:09:17 PM UTC+5:30 [email protected] > wrote: > >> Praneeth, >> >> We volunteer our time and will reply when and if we can. >> >> Your list of forces looks interesting and useful. I recommend reading the >> force related sections of Kane & Levinson 1985, as those would be obvious >> places to take forces ideas from. I'm currently writing a force chapter in >> my book that has some examples (these are still in draft form and likely >> incorrect): >> https://github.com/moorepants/learn-multibody-dynamics/pull/57 >> >> There should be no need for a system or anything from pydy. We need valid >> mathematical descriptions of a variety of common forces that will work >> nicely with our code generators for efficient numerical implementations. >> >> Jason >> moorepants.info >> +01 530-601-9791 <(530)%20601-9791> >> >> >> On Tue, Apr 5, 2022 at 3:48 PM praneeth ratna <[email protected]> >> wrote: >> >>> Hi jason, >>> >>> Could you please provide your feedback on my previous two emails, So >>> that I can start writing my proposal and since there isn't much time left >>> for proposal deadline. >>> >>> Thanks, >>> Praneeth >>> >>> On Monday, April 4, 2022 at 11:38:48 AM UTC+5:30 praneeth ratna wrote: >>> >>>> Jason, >>>> >>>> Regarding the implementation, do you suggest similar to pydy engine? So >>>> we also need to create a System >>>> <https://pydy.readthedocs.io/en/stable/system.html> class similar to >>>> the one pydy has? Also could you suggest any sources for some trivial >>>> cases >>>> of muscle force, actuator force and aerodynamic force models, could you >>>> provide feedback on whether the model specified in my previous mail are >>>> useful or not, so that i can include them in my proposal. >>>> >>>> Thanks, >>>> Praneeth >>>> On Monday, March 28, 2022 at 4:22:26 PM UTC+5:30 praneeth ratna wrote: >>>> >>>>> Hi jason, >>>>> >>>>> I have at present written down the following models: >>>>> >>>>> 1. Linear hooke contact model >>>>> 2. Non linear hertz model >>>>> 3. Linear Kelvin-Voigt Contact Model >>>>> 4. Nonlinear Hunt and Crossley Contact Model >>>>> 5. Nonlinear Hunt and Crossley Contact Model >>>>> 6. Nonlinear Flores et al. Contact Model >>>>> 7. multi_mass_spring_damper() >>>>> >>>>> <https://pydy.readthedocs.io/en/stable/models.html#pydy.models.multi_mass_spring_damper> >>>>> 8. n_link_pendulum_on_cart() >>>>> >>>>> <https://pydy.readthedocs.io/en/stable/models.html#pydy.models.n_link_pendulum_on_cart> >>>>> >>>>> 7 and 8 are taken from pydy, are they non trivial cases? Also could >>>>> you suggest any resources for muscle force, actuator force and >>>>> aerodynamic >>>>> force models which are useful for the user? >>>>> I have taken 1 to 6 from the here >>>>> https://www.researchgate.net/publication/299604992_Contact_Force_Models_for_Multibody_Dynamics, >>>>> >>>>> are they useful cases? >>>>> >>>>> Thanks, >>>>> Praneeth >>>>> >>>>> On Saturday, March 26, 2022 at 1:08:09 PM UTC+5:30 [email protected] >>>>> wrote: >>>>> >>>>>> Praneeth, >>>>>> >>>>>> Yes we should have a linear spring and damper force that is premade, >>>>>> but that is really just a trivial case. The GSoC project should be >>>>>> focused >>>>>> primarily on adding non-trivial forces. >>>>>> >>>>>> Jason >>>>>> moorepants.info >>>>>> +01 530-601-9791 <(530)%20601-9791> >>>>>> >>>>>> >>>>>> On Sat, Mar 26, 2022 at 7:29 AM praneeth ratna <[email protected]> >>>>>> wrote: >>>>>> >>>>>>> Hi jason, >>>>>>> >>>>>>> I have gone through the examples of pydy and your courses that you >>>>>>> have mentioned. For example: Here >>>>>>> https://pydy.readthedocs.io/en/stable/examples/mass-spring-damper.html, >>>>>>> the plan is to implement the same thing in a class so that user can >>>>>>> call >>>>>>> the linear spring damper object whenever it is required and use >>>>>>> numerical >>>>>>> methods that can operate on force objects, is it the right thing? Also >>>>>>> is >>>>>>> there any priority for forces that should be implemented first since >>>>>>> there >>>>>>> many kinds of forces to be implemented. >>>>>>> >>>>>>> Thanks, >>>>>>> Praneeth >>>>>>> >>>>>>> On Friday, March 25, 2022 at 3:45:55 PM UTC+5:30 [email protected] >>>>>>> wrote: >>>>>>> >>>>>>>> Praneeth, >>>>>>>> >>>>>>>> Checking out examples in pydy, sympy, and my various courses (MAE >>>>>>>> 223, ENG122, ME41055) are also good locations. >>>>>>>> >>>>>>>> >>>>>>>> Jason >>>>>>>> moorepants.info >>>>>>>> +01 530-601-9791 <(530)%20601-9791> >>>>>>>> >>>>>>>> >>>>>>>> On Fri, Mar 25, 2022 at 9:00 AM Jason Moore <[email protected]> >>>>>>>> wrote: >>>>>>>> >>>>>>>>> Hi Praneeth, >>>>>>>>> >>>>>>>>> I recommend looking at force types in various physics engines to >>>>>>>>> get ideas. The rest would really come from academic papers and text >>>>>>>>> books. >>>>>>>>> >>>>>>>>> Jason >>>>>>>>> moorepants.info >>>>>>>>> +01 530-601-9791 <(530)%20601-9791> >>>>>>>>> >>>>>>>>> >>>>>>>>> On Wed, Mar 23, 2022 at 5:31 AM praneeth ratna < >>>>>>>>> [email protected]> wrote: >>>>>>>>> >>>>>>>>>> Hi all, >>>>>>>>>> >>>>>>>>>> I have already posted regarding my interest in the idea >>>>>>>>>> *Implementing >>>>>>>>>> Specific Forces and Torque objects *but have not recieved any >>>>>>>>>> reply yet,Could the potential mentor please guide me on what has to >>>>>>>>>> be done >>>>>>>>>> in this project and some resources, so that I can start working on >>>>>>>>>> my >>>>>>>>>> proposal since there isn't much time left. >>>>>>>>>> >>>>>>>>>> Thanks, >>>>>>>>>> Praneeth >>>>>>>>>> >>>>>>>>>> On Friday, March 18, 2022 at 12:29:04 AM UTC+5:30 praneeth ratna >>>>>>>>>> wrote: >>>>>>>>>> >>>>>>>>>>> Hey! >>>>>>>>>>> >>>>>>>>>>> While going through the GSOC 2022 ideas I have come across the >>>>>>>>>>> idea of Implementing Specific Forces and Torque objects which i >>>>>>>>>>> found >>>>>>>>>>> interesting. There are many possible examples mentioned by Jason K. >>>>>>>>>>> Moore. >>>>>>>>>>> And I'm able to find a resource for contact force models : >>>>>>>>>>> https://www.researchgate.net/publication/299604992_Contact_Force_Models_for_Multibody_Dynamics >>>>>>>>>>> >>>>>>>>>>> which i found useful. Are there any resources for the examples >>>>>>>>>>> mentioned in >>>>>>>>>>> issue which can helpful for understanding the implementation of >>>>>>>>>>> concept >>>>>>>>>>> other than contact force models? >>>>>>>>>>> >>>>>>>>>>> I'm thinking of adding different classes for different type of >>>>>>>>>>> force models and torques and that can be used to create a force >>>>>>>>>>> object or >>>>>>>>>>> torque object of that type also numerical methods can be added to >>>>>>>>>>> individual classes. >>>>>>>>>>> >>>>>>>>>>> I would request Jason K. Moore to guide me on how to move >>>>>>>>>>> forward in this project, regarding the implementation and about >>>>>>>>>>> what all >>>>>>>>>>> kinds of forces and torques should be implemented so that i can >>>>>>>>>>> start >>>>>>>>>>> working on my proposal. >>>>>>>>>>> >>>>>>>>>>> Thanks, >>>>>>>>>>> Praneeth >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> -- >>>>>>>>>> You received this message because you are subscribed to the >>>>>>>>>> Google Groups "sympy" group. >>>>>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>>>>> send an email to [email protected]. >>>>>>>>>> To view this discussion on the web visit >>>>>>>>>> https://groups.google.com/d/msgid/sympy/f010d4bf-5986-4ac2-946f-0d306697a36cn%40googlegroups.com >>>>>>>>>> >>>>>>>>>> <https://groups.google.com/d/msgid/sympy/f010d4bf-5986-4ac2-946f-0d306697a36cn%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>>>>>>> . >>>>>>>>>> >>>>>>>>> -- >>>>>>> You received this message because you are subscribed to the Google >>>>>>> Groups "sympy" group. >>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>> send an email to [email protected]. >>>>>>> >>>>>> To view this discussion on the web visit >>>>>>> https://groups.google.com/d/msgid/sympy/d61600ae-f566-44c5-9548-ef79b5e2c423n%40googlegroups.com >>>>>>> >>>>>>> <https://groups.google.com/d/msgid/sympy/d61600ae-f566-44c5-9548-ef79b5e2c423n%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>>>> . >>>>>>> >>>>>> -- >>> You received this message because you are subscribed to the Google >>> Groups "sympy" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> >> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/sympy/0e43d682-13d4-4065-98fe-fceb7fd6fd5fn%40googlegroups.com >>> >>> <https://groups.google.com/d/msgid/sympy/0e43d682-13d4-4065-98fe-fceb7fd6fd5fn%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >> -- You received this message because you are subscribed to the Google Groups "sympy" group. 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