Inertia Jig at competition?

[EPMPaul]

Hi,

Was just wondering if it had ever been proposed/suggested to have an inertia jig at the competitions. The interest of this for all teams would be that if every team gave chassis parameters you could statistically evaluate basic design choices in future designs

Say every team gives the following parameters:
- CG Height
- Weight
- Tracks
- Wheelbase
- Engine Type
- Aero or not
- Wheel type(10 or 13 inch)

If say you had a standard jig to which all teams have to adapt to(ie set some hardpoints that all team would have to attach to through a plate or something). Every willing team would pass and have the data for all teams.

This would mean that if you were to fit some sort of statistical model you could evaluate the inertia implications of a certain design choices which you can't otherwise evaluate in a reliable quantitative way(ie longer wheelbase , larger track, engine and wheel type).

On top of that could be more data for the design judging and a common organization may provide a more reliable measure of inertia than team jigs(I'm sure a few teams do it properly but speaking from my own experience, measures made in our team are sometimes iffy) as well as providing a meaningful/reliable comparison between years for teams wanting to compare evolutions in design

I figure there are two ways you could organize this.

A/ SAE or some kind of competition sponsor organizes the design/implementation/operation of the jig
B/ You run some kind of TTC type of organization where everyone throws in whatever the estimated cost of the jig and

Here are a few of the requirements I thought should be necessary:

- Precision of 5% for measure of inertia between 25kgm^2(approximate roll inertia for smallest cars) and 130kgm^2(approximate largest yaw
inertia in FSAE). Note that pitch inertia is gonna be somewhere in between. This requirement means you,re gonna need some fairly accurate DAQS.

- Dimension of platform approximately 150in*150in (I think our car,s maximum dimension is something like 120in so 150in*150in should be appropriate for most teams)

- Has to fit in something like a 18ft trailer


Anyways. Just a thought

[EPMPaul]

Hi,

Was just wondering if it had ever been proposed/suggested to have an inertia jig at the competitions. The interest of this for all teams would be that if every team gave chassis parameters you could statistically evaluate basic design choices in future designs

Say every team gives the following parameters:
- CG Height
- Weight
- Tracks
- Wheelbase
- Engine Type
- Aero or not
- Wheel type(10 or 13 inch)

If say you had a standard jig to which all teams have to adapt to(ie set some hardpoints that all team would have to attach to through a plate or something). Every willing team would pass and have the data for all teams.

This would mean that if you were to fit some sort of statistical model you could evaluate the inertia implications of a certain design choices which you can't otherwise evaluate in a reliable quantitative way(ie longer wheelbase , larger track, engine and wheel type).

On top of that could be more data for the design judging and a common organization may provide a more reliable measure of inertia than team jigs(I'm sure a few teams do it properly but speaking from my own experience, measures made in our team are sometimes iffy) as well as providing a meaningful/reliable comparison between years for teams wanting to compare evolutions in design

I figure there are two ways you could organize this.

A/ SAE or some kind of competition sponsor organizes the design/implementation/operation of the jig
B/ You run some kind of TTC type of organization where everyone throws in whatever the estimated cost of the jig and

Here are a few of the requirements I thought should be necessary:

- Precision of 5% for measure of inertia between 25kgm^2(approximate roll inertia for smallest cars) and 130kgm^2(approximate largest yaw
inertia in FSAE). Note that pitch inertia is gonna be somewhere in between. This requirement means you,re gonna need some fairly accurate DAQS.

- Dimension of platform approximately 150in*150in (I think our car,s maximum dimension is something like 120in so 150in*150in should be appropriate for most teams)

- Has to fit in something like a 18ft trailer


Anyways. Just a thought

[BillCobb]

You have the opportunity to measure CG height during the rollover stability platform evaluation. All you need is an accurate scale and an angle measuring device. That could be a start. You could get almost everything requested during that station event. Then you need a team to do the work, a database to hold it and a procedure that teams won't dispute. I don't think the inertia data has all that much extra value considering the mechanization of a test. Maybe somebody could hire a crane and do a trifilar pendulum to get yaw inertia. Would your school provide the funds, computer, and legwork to get this job done? Probably only need to do it a year. Then correlate configurations to inertias and autocross event position. K^2/ab < 1 is always a winner.