DIY PRO 2DOF + ZTLS Car Simulator (A Zappadoc Concept)





EKSIMRacing foundation a non profit organization

As you know I’m the owner of EKSIMRacing foundation a non profit organization dedicated to promote the sim racing (including flight-sim now) since 2007.

All our projects are funded by donations or self-financed with equity. In short, our mission is to develop professional grade software to increase the immersion and improve the gaming/training experience of our users (casual to PRO), to discuss/collaborate with game studios to improve their API (telemetry of the car), to discuss, design, improve, help game hardware manufacturer to make better sim racing products and more generally to make transparent as possible the interface between the user and the game/simulation using from full PRO car racing motion simulator to a simple virtual racing dash display on Android phone.

MotionMax Manager is in development since 2015, a motion simulator software for 2DOF and 6DOF motion simulator platform.
A simulator machine for driving racing car or aircraft at home. The 6DOF machine is already in production by FREX Japan. it’s powered by our software MotionMax Manager (MMX6).

The FREX 6DOF is the most realistic car racing simulator available today at this price range suitable for PRO training and track learning and recommended for those who can afford it.This great 6DOF machine is also available in kit.


R&D “4 legs” 3DOF+ simulator has been dropped

The R&D around the “4 legs” 3DOF+ D-BOX style simulator has been dropped, the results are very bad in terms of realism and driving feel. The PROs are unanimous in saying that driving these kind of simulators provide a bad feeling with SCN actuators, very blurry track feeling and not natural, slow responsive, not enough amplitude, not enough “brutal” compared to real racing car. This kind of simulator requires very expensive linear electric actuators to be suitable for real car racing experience and is not longer supported.



DIY “PRO grade” car racing simulator project

My concept is more about making a perfect combination with MotionMax 2DOF and the simulator, a DIY “PRO grade” car racing simulator project with an optimized FREX Style 2DOF + a ZTLS (Zappadoc Traction Loss System) using affordable SCN6 actuators.


2DOF Invented by Shige Tanaka  in 2005


The 2DOF simulator concept with 2 electric linear actuators+pivot is not new and has been invented in 2005 (15 years ago as of this writing) by Shige Tanaka for which I have a lot of respect for the man and for his contribution to the sim racing community.

2005 2020

He’s the boss of FREX Japan. His 2DOF concept is still the REFERENCE today. I’m always fascinating by people who are capable to spend a lot of money for a simple 2DOF to a manufacturer who literally stole the invention of Shige!


The DIY 2DOF+TL Project Not for Sale

I’m happy to share with you my concept and design and give you all the needed info to help you to build a very good car racing motion simulator but I’m not going to create and sell a ready-to-use hardware simulator kits.

Buy it from FREX Japan if you want a complete solution and If a manufacturer is interested he can contact me, but for now this project is for PERSONAL USE ONLY under CC BY-NC-SA 4.0 license and forbidden for any commercial use. Read the license HERE.

However, this DIY simulator project is easy to build (although some skill with aluminum frames are needed), inexpensive compared to PRO solution (which are overpriced IMHO), suitable for casual user for entertainment to real PRO driver for training and track learning. Optimized for MotionMax software 2DOF (MMX2+TL) which is powerful and very easy to use with more than 50 games/simulations supported.


The ZTLS (Zappadoc Traction Loss System)


I created the ZTLS (Zappadoc Traction Loss System) to get a compact TL system and ultra responsive.

The ZTLS is under Creative Commons Attribution-Noncommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) license and requires my written consent to be marketed or used in any business/commercial context.

In short, it’s for *PERSONAL USE ONLY* and forbidden for any business/commercial. Read the license HERE.

The 2DOF is good for car racing simulation, the braking/acceleration, bumps and track relief are restored superbly but this doesn’t give you all the force involved. The lack of heave DOF  is acceptable on racing car but the lateral motion on oversteer / understeer are missing and the simulator fails to restore natural driving feeling to the driver… A real car simulator needs  an efficient traction loss (TL) system.

The main issue of almost all traction loss system available today in racing simulator are:
– the software which are unrealistic and overreacting, spectacular okay! but not realistic, you’re a racer driving a car not in a pinball machine… I wonder if developers of these “pinball” software really drove a race car in their life?
– also, A BIG PROBLEM is the use of a “articulation/ball joint” between the structure of the simulator and the dedicated TL actuator to compensate for the angle change when actuator is moving forward and backward.

This ball joint (usually a rod end) takes some time to deploy, this “moment” of deployment of the joint before the simulator actually moves introduces latency, the longer the rod with knee of the ball joint, the more the latency increases, this is a big problem.


ZTLS is directly in contact with the simulator

The TL system must be ultra responsive, this is why the ZTLS is directly in contact with the simulator (no ball joint).


Efficient and with a very fast response combined with MotionMax Manager, the ZTLS allows the actuator to rotate on itself using a swivel plate and during the rotation the actuator is continuously in contact with the simulator structure and keep pushing or pulling with zero latency.


Getting Started To Build Your Own Simulator

MotionMax Manager 2DOF+ZTLS license (MMX2) is available from EKSIMRacing HERE or FREX Japan, HERE,

The DIY 2DOF+ZTLS project is based on 2DOF+TL Motion FREX KIT available from FREX, HERE


Mounting Your 2DOF+ZTLS Simulator


Disclaimer for all information related to the DIY 2DOF+ZTLS Project

Neither nor any of its providers of information shall have any liability for the accuracy of the information contained in the Service, or for delays or omissions therein. None of the foregoing parties shall be liable for any third-party claims or losses of any nature, including, but not limited to, lost profits, punitive or consequential damages.
The information provided within these pages is not guaranteed to be accurate, nor does the management take responsibility for it. The information comes from other sources and therefore may be wholly unreliable, and the management does not guarantee its suitability for any purpose.
Although the information contained herein may be completely useless, all rights are retained by their respective owners, including, but not limited to, the right of reproduction, the right of distribution, and the right of passage. specifically disclaims any implied warranties or merchantability or fitness for any particular purpose and shall in no event be liable for any loss of profit or any other commercial damage, including but not limited to special, incidental, consequential, or other damages, even if advised of the possibility of such damages.


Mounting the Simulator

Mounting your simulator is easy, get some tools, order motion software and 2DOF+TL kit, get the frames using the provided parts list and build it!


Interested To Build My Own 2DOF+ZTLS?

Hardware/software requirements, parts list and getting started Info to build your simulator are available to all registered members of EKSIMRacing, a dedicated section has been created to get all the info in one place, see HERE.