My project : Zero-gravity, 4dof

Hi Fern,
Your work is fantastic, and i'm amazed that we hade the sa me idea for the rear position of the two motors, the difference is that i Will use at the center or graviti a cilinder but all rotate on that center! My limitation is that a don't now a word of progreamming and i think TO use a Arduino mega, so my question is if you can post the firmware TO flash on Arduino,

Thanks

Valentino
:hi:

Hi,Fern. Realy Great work!!! :clap:

Can you tell more about this stabilizer bars? If it possible - can you make kinematic sketch or detailed photos with this bars?

Hi Valentino

Thanks for your comments.

Flashing firmware works ONLY if your microcontroler has the correct hardware connected to the right pins. You could not use my code without a lot of modifications. I have commands that will start the compressor, set the air pressure, set min/max position on each motor, report current status, send the controller in sleep mode, read current air pressure, bleed air pressure, etc. I also have a complex custom shield on top of it with all type of electronics components: ic, transistors, resistors, diodes, capacitors and 15 connectors connecting 41 wires. I do not have any time now to cleanup the code and there are parts I do not want to publish.

Your options are :
- use 2-K8055 (I do not recommend it's bigger sister VM140, my experience with this board was a failure)
- learn to program
- other

Arduino guys have made it quite simple to write a sketch for any Arduino board and the code can also be used with minimal modifications with LeafLab' Maple board and Olimex Maple. These 2 boards are less expensive than Arduino and much more powerfull. They use 32 bit instead of 8 and the IDE is derived from Arduino IDE. There is also the Pinguino which is multi platform.

Hi prilad,

Before using a stabilizer bar there are 2 things you must be sure are right
1 - proper balance : make your pivot as close as possible right under the cg. You can verify this using scales (search: calculate cg) or a round tubing under your seat frame.
2 - have powerfull enough motors.

I use a stabilizer bar because of a heavy seat frame and the rod end that support it is attached about 8 inches below the CG. On leaning the CG shifts in relation to the support point. The bar helps the motors bring the seat back to center. Do I really need it ? Not sure, I decided to install one when I was trying to use the Velleman VM140 which was a failure. Though the seat is nose heavy I only selected to have one bar for lateral movement.

The bar is simply U-shaped with 12in length and 9in arms. The ends are rounded to connect the links. It is 8mm and the torque is about 20 lbf inches (2.26 Nm)
http://www.cleavebooks.co.uk/scol/cctorq.htm
If I had to do it again, I'd go with 10mm instead that would give about 40 lbf inches (4.52 Nm)

Do not forget that I have to move the pedals, steering and shifter. If you have only a seat mover, it is not easier because you may pull on your steering and push hard on the pedals changing the force needed to bring it back.

If you decide to use one you can spend up to 200$ for the bar, rod ends and linkage.

Fern

Thanks Fern,

In this days i studied very much to programming and i understud the pid and how to do! I thested the arduino whit code written by me but very simple to learn arduino's commands, now with a friend i will write the code, and include auto calibration with max and min switchs and a safe button and from yours the low position to seat! I hope to do all this weekend

If you send my the firmware i can cleen it only to understend the work to do

Thanks and best regards

Valentino

Beautiful! Like your design. Text looked a long time, they would understand

Good sim I built my only adjust left. Once I understand how to make