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[Raceray]

Welcome Mutlu,
great to hear your interest in building Thanos interface and your own simulator. Feel free to describe your whole project at the DIY Simulator section and keep us informed.
Kind regards, René

[christian]

Hello Thanos,
great job you have here done
I am a simracer from Germany and I will rebuilt your AMC motion-controller for my SimForceGT like Ego`s.
Today the pcb is arrived and I will start.
I hope you can help me if I have question.

sorry for my english

regards
christian

[tronicgr]

I think that you may be pleased to hear about the progress on the development of optical encoder support for AMC1.5.

I made custom quadrature decoder controller based on a ATtiny2313 that reads and decodes the signals from an Optical Encoder. The ATtiny2313 runs on 20Mhz crystal that means that can deliver 20MIPS processing power!!! Its output is parallel to be able to read it as fast is possible (I measured 20 uS access time for retrieving a 16bit value).

I plan to interface it on AMC1.5 by using another ATtiny2313 that will be an I2C slave device with transfer rate of the maximum speed of 400kHz. Then with only two wires you could connect up to 8 ATtiny2313 quadrature decoder controllers in the same two I2C ports of the AMC1.5. Addressing is not an issue as each I2C slave device can have DIP switch selected address.

As this decoder is 16bit and allows 65535 positions, I will also alter the AMC1.5 firmware to support 16bit input for the position values. As you may notice this will work only with x-sim² Profiler2, that its new USO module can send 16bit values (the old profiler1.8 can send only 8bit values)

Anyway for the development I used an HEDS 9100 (500 cpr) quadrature optical encoder that is attached on a FESTO DC servo motor that Monast send me recently, to help me with project. As the motor has planetary gear ratio of 1/13.73 , I read 6865 positions per full revolution of the output axis. The datasheet of the motor which I took apart is this one: http://www.festo.com/INetDomino/files_0 ... PSI-US.PDF

Now comes the fun part: The motor itself has 6096 RPM speed and since the optical encoder disk is 500 cpr I have to read 3048000 positions per minute or 50800 positions per second if the motor runs in full speed!!!!!! Guess what! I tried it and it works!!! The ATtiny2313 quadrature encoder controller doesn't miss a pulse!!!!!

These are some photos of the breadboarded ATtiny2313 decoder circuit, interfaced directly (in parallel mode) to the AMC. As you can see it took all the eight ADC ports and all the four RC servo ports to interface it, that is impractically for only one quadrature decoder, that's why I will interface it thru I2C in the final.

For better resolution of the video click below and choose "Watch in high quality"
http://www.youtube.com/watch?v=8qmNt4erRXc


Best Regards, Thanos



Notice to all that I have send me email these days and didn't answer them yet: Sorry you guys, I rather prefer using my spare time on development of these cool electronics, than spending endless time on replying on matters that already are answered here in this thread. I try to reply some of them slowly when I'm not at home, but the queue of emails seems to increase day by day

[egoexpress]

AMC with 16bit encoder

[wannabeaflyer]

Tronic Got another question and realise you have a backlog of E-mails from eager customers so answer if and when you can .. While still waiting for some of the other elements for my 2DOF Simforce GT type sim i thought i would use the time to make a Working model based on RC servos just to learn about how to Properly setup and get X-Sim running with Your Electronics, have seen the stuff that you and Plannmix have done and wondered if you had a block diagram to show how the servos need to be connected and any notes on getting the model running before i connected my big motors ( do i need 2 PC networked etc ... PS may have to change the electric Wheel chair Motors back to Wiper motors on my design because i found some more info on the motors and they seem to indicate 26Amps ( and double ) so i may be pushing my luck trying to use the Dual H Bridge card to drive these.. Shame as i thought that with the built in electric brake and gearbox these motors would be easly provide the motion i needed Dammmm.. Still Not the end of the world as they will be used for the Plane sim ..

[Mambo]

How hard is curent limiter ? If you insert it in front of H-bridge than you have confidence that you dont destroy it.

[tronicgr]

For current limit you can use some car fuses in the power line, just before the hbridge power input...

post6629.html#p6629


@wannabeaflyer
You cannot use the simple RC servos on the h-bridge!!!! They have their own hbridge inside them!!!

On the other hand you can modify them! You can strip its electronics board and leave in the case only the motor and the potentiometer! Then you will have four cables coming out of each modified rc servo, two from the motor and two from the potentiometer... You can then connect them to the H-bridge exactly as the large motors!!! The only thing to worry then is to match the direction of the motor with the direction of the potentiometer!


Regards, Thanos

[wannabeaflyer]

Many thanks for the info thanos, went to a model aircraft show last week and bought some cheap servos there with just this project in mind so will pull them apart ( Carefully ) and see how it goes.. ps got all the bits to Build your H bridge circuit at last so will keep you posted

[Mambo]

Well i mean it more like restriction. For example H bridge can take 10A and motor on stall 20A so if you set limiter to 10A you cant burn hbridge (but you got only 1/2 of motor torque)

[RobiD]

Hi Thanos,

Haven't posted for a while but read everytime there is a new post.

Just wanted to update you on my progress.

First of all, I have build the Mjoy and flashed it (had a few problems flashing it but all done and recognised by the computer)

Built the controller and the H-bridge boards. Had a problem at first, the led on the Rx molex side didn't light up. It still flashed but the LCD lit but didn't show anything.

After much problem solving, turned out the be the molex cable I built (Rx), the center pin wasn't contacting properly. Also made the mistake of running on 12vdc instead of 5 to 9. (yes the magic smoke escaped out of the 1000uf cap closest to the power plug)

Used this board to flash the MJoy as well. Took me a while to find out that the USB needs to be connected when flashing the MJoy.

One issue I appear to be having, the LCD is very slow to respond for example, if I push the Alps reset button, it can take around 10 seconds plus to respond, then it says START for about 10 to 15 seconds then display the firmware details.

Is this normal or do you recognise a problem?

Thanks again for your great work.

David
Australia