2DOF to 4DOF

2DOF to 4DOF
I would like to start by thanking all the people around the community in having made this project possible.. My biggest dream, as racing enthusiast, has always been to be able one day to have such simulator of my own. You guys have made this possible!

My first ever attempt.. a simple seat and frame..




Then improved when sim sites found...
(12V car battery )




and this to an almost masterpiece with 2DOF..



But although very exciting, something was still missing, a 3rd DOF.


The introduction of this frame added an extra sway feeling to my rig, but the use of standard rubber castor wheels made the movement slack and ' very heavy' when setting in the chair. Few types of wheels options were tested, first was the 2 castor rubber wheel which did not work, then swopped to nylon wheels, but friction still too high and movement still restricted.; and finally, the use of spherical metal bearing did the trick. The minimum contact point meant full sway effect with minimal afford.

These bearing come with a large inner hole I used a piece of a timber rod as bush and the castor wheels metal holder as housing. The shaft holes of the castor wheels housing was also modified as the new bearing has a larger outside diameter.

OVERVIEW OF COMPONENTS:

• 2x12VDC Fiat X1/9 lights retractors motors with 40mm radius action
• 1x 24VDC garage sliding door motor with 40mm radius action.
• Universal Joint from a Nissan car steering column
• M10 Rod End - Female Metric
• Controller AMC1.6 and Dual Single H-Bridge DSMhb1.2b by Thanos (Tronic Gr)
• PSU 13.8VDC @ 40Amps from Jaycar, code MP3089
• Ghepardo Fixed back Racing seat with 5 seat position
• Force Feedback Logitech G27 Steering and pedals.
• SimTools Manager and Engine
• Overall total frame weight +/-46Kg (excluding sway frame)
• 2x Spherical Bearing UC206-17

DESCRIPTION OF UNIT:Full Square steel tube main structure.

• The adjustable seat frame allows an intermediate frame to be placed between the adjustment slider and the actual seat. This allows only the feet portion of the main moving frame to move by about 120mm, thus keeping the driver body always in the same position.
• Maximum amperage reached at full blast is a mere 10Amps total. (at +/-100kg full load)

Concerning the framework, I would like to suggest having the Steering frame bolted to the Slider frame rather than welded. (2 x bolts and nuts per side)
This allows for dismantling if transport needed.



The SketchUp 8 drawing can be uploaded from:
http://www.mediafire.com/download/x0ibxpyz3c084ga/2DOF 3DOF chair.skp

If interested in the actual components' sizes, you can download the CAD pdf drawing here:

http://www.mediafire.com/view/i9tz9enm995jizv/2DOF 3DOF Chair Components.pdf

But please, note that to match your motor or selected components, you will require to alter or adjust some of the component's size or shapes. So, use this as a guideline only!

Additional pictures below are showing the punched angle bar holding the aluminium footrest while strengthening the whole sliding frame. Also close up of the rear sway wheels and position pots.
Bucket seat removed to show framing.

AS I was struggling to solve the correct 3DOF coding for the AMC1.6 Controller, I have designed a new basic program to work with the new MicroMite (PIC32) microcontroller and finally managed to see all 3 axis working.



Very fast response and very simple to modified as the programming is written in Basic.
More informations at:

http://www.xsimulator.net/community/threads/micromite-3dof-controller.7370/


But yet, not being satisfied with all the above work and mods, recently I added 1 extra movement to my rig, acceleration and braking. Giving a full 4DFO movement.

This was easily done by welding 4x 40x40x40mm angle brackets to the 4 extremities of the bottom base and then bolting the 4 sets of linear bearing to them.



With the linear bearing shafts are mounted on a MDF base



MDF components in the pdf file:



The motors driver (Micromite controller) then upgraded to allow the 4 inputs.




Additional Images:


But finally,




This has taken few years to developer to this top 4DFO model. Although the structure might look a bit 'soft' to many, the unit was tested by drivers of double my weight... With the analog current meter showing only few Amps under loads and no flexibility in the frame structure.

Final unit sizes/movements:


Enjoy it!