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Steering rig start

Started by h106frp, January 24, 2015, 11:29:48 AM

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h106frp

January 24, 2015, 11:29:48 AM Last Edit: January 24, 2015, 11:54:02 AM by h106frp
Started building so i thought i would start a thread. Got most of the bar bits together and the main steer axis. Yoke is Aprilla RS. Aluminium box section is temporary for now.


ended up making a switch housing from alloy billet, all done on the drill press.

Throttle pulley and potentiometer are hidden in the fork stanchion clamp with fake fork tops from aluminium.


The steering spindle should allow for drive pulleys and strain gauges to hopefully develop torque steer and force feedback. After a recent discussion thread i am thinking of adding a engine rpm linked vibration motor in the space that used to house the steering lock as this could be quite straight forward to do and i already have the electrical signals as they are the same as the ones that drive my rev counter.

I was hoping to put off the horizontal roll axis spindle for a while as it will need a bit of machining for the raked 'gimbal' attachment but i now see that i need to get on with this bit next.

Got most of the hydraulic bits but need to make some adapters before i can assemble, hydraulic connections seem to have no real standards with a vast mix of thread diameters and pitches >:(

Just a start... lots to do :)

Just to add, really pleased with how nice this 'feels' already. The mass of the bars with a smooth turning action just feel so right :)

BOBR6 84

All nice and tidy mate.. looks good  8) just need some Renthal racing grips now  ;D

teeds

Coming together well with some nice touches in there already fella

doubledragoncc

Really clean build H. Very nice. What did you decide to use for brake and clutch signal in the end?

Keep it up buddy its cool

DD
GPBOC Live Streams: https://www.youtube.com/c/IASystemsComputerControls; i7 12700K 5.1GHz Z690 ASUS Strix Z690-A Mobo 32GB 3600MHz DDR4 RAM ASUS Strix RTX3080 OC 10GB DDR6X ASUS Ryujin 360 AOI Cooler ROG Thor 1200w PSU in ROG Helios Tower Case.

h106frp

Managed to scrounge up a couple of old 100bar pressure transducers - so the hydraulic adapters between the 10mm bike fittings and 12mm landy clutch slaves are going to incorporate a G1/4' pressure tapping which should be quite neat. Have not checked the transducers are working yet so hope they are ok.

As a fall back if the transducers are no good i will use the simple load cell scheme on the hydraulic cylinder, still sketching up the conversion of the cylinders to simulate the braking load points but the piston and cylinder design should make this quite simple as its already designed to take a rod in compression that would normally operate the clutch arm.

doubledragoncc

Sounds like a good plan. Its how I will offer the higher priced systems but the lower priced will have just potentiometers for all analog axis. Im just writing my business proposal for Leo Bodnar that he asked for and hoping to get him in on the steering FFB as he is the bollocks when it comes to steering systems.

I think that with the cheap hydraulic parts you can buy it should still be affordable, I am looking into other transducers as I have found some I THINK might work but not gonna lay my head on the chopping block yet lol.

DD
GPBOC Live Streams: https://www.youtube.com/c/IASystemsComputerControls; i7 12700K 5.1GHz Z690 ASUS Strix Z690-A Mobo 32GB 3600MHz DDR4 RAM ASUS Strix RTX3080 OC 10GB DDR6X ASUS Ryujin 360 AOI Cooler ROG Thor 1200w PSU in ROG Helios Tower Case.

h106frp

If you can find a cheap viable transducer that would be great. I'm trying to build in the flexibility to try different ideas with this rig. It will be a WIP for quite a while i think ;)

doubledragoncc

I know that feeling. Ive been building my systems for 5 years now and change them every time lol. Its hard making a system that is at the same price bracket or around that of a good steering wheel system. I dont think I can retail for less than £350 to be honest as so much more is involved than a wheel system. People dont realize the cost of NEW electronics and parts. I cant retail used bike parts lol. But I sorta got a few tricks up my sleeve for wheel set owners.............watch the next episode lol.

DD
GPBOC Live Streams: https://www.youtube.com/c/IASystemsComputerControls; i7 12700K 5.1GHz Z690 ASUS Strix Z690-A Mobo 32GB 3600MHz DDR4 RAM ASUS Strix RTX3080 OC 10GB DDR6X ASUS Ryujin 360 AOI Cooler ROG Thor 1200w PSU in ROG Helios Tower Case.

HornetMaX

Quote from: h106frp on January 24, 2015, 05:02:43 PM
Managed to scrounge up a couple of old 100bar pressure transducers - so the hydraulic adapters between the 10mm bike fittings and 12mm landy clutch slaves are going to incorporate a G1/4' pressure tapping which should be quite neat. Have not checked the transducers are working yet so hope they are ok.

As a fall back if the transducers are no good i will use the simple load cell scheme on the hydraulic cylinder, still sketching up the conversion of the cylinders to simulate the braking load points but the piston and cylinder design should make this quite simple as its already designed to take a rod in compression that would normally operate the clutch arm.
Would be very interesting to compare the output of the two sensors in terms of precision, noise, response time etc.

MaX.

h106frp

The mark up on new parts by the time they reach Europe does make them expensive, when you get going and start buying commercial volumes of stock do you think you will be buying items direct from suppliers and selling them on from your site? I'm mainly thinking transducers for force/pressure/displacement. I like the concept of the hall effect potentiometers but only buying 2 or 3 makes them expensive (about 3* the cost of conventional items), this may be balanced out by the vastly extended life span and low noise/precision of these devices though and could be an option/warranty consideration for a commercial device.

For DIY building, the only real expense for the hydraulics is the transducer, using the 'bathroom scale' device and shopping around its probably about £50 for the brake unit complete, pressure transducers alone (in Europe) as this much alone :(. Not cheap, but alongside the throttle probably the most important item for realistic control, its hard to judge how the sim bike is responding to displacement (joystick) braking.

Thanks for the links to Leo's site, the BU0836A looks reasonable value for a properly laid out board plug and play solution, a review of the software side of this controller would be useful as he does not give much detail on his site. I will probably use this for the conventional 'joystick' inputs and run the GPB roll and steer signal through my own board alongside the instrument cluster signals.

The roll axis force feedback could be quite simple for my desk mount setup as you do not have space and weight concerns. The steer axis will need a bit of jiggling to fit gearing and the most compact/low weight motor set-up. I want to use toothed belts for precision, low noise and durability but you do need quite a bit of space to achieve a reasonable reduction ratio.




h106frp

January 25, 2015, 10:21:43 AM #10 Last Edit: January 25, 2015, 10:27:05 AM by h106frp
Quote from: HornetMaX on January 25, 2015, 10:07:42 AM
Quote from: h106frp on January 24, 2015, 05:02:43 PM
Managed to scrounge up a couple of old 100bar pressure transducers - so the hydraulic adapters between the 10mm bike fittings and 12mm landy clutch slaves are going to incorporate a G1/4' pressure tapping which should be quite neat. Have not checked the transducers are working yet so hope they are ok.

As a fall back if the transducers are no good i will use the simple load cell scheme on the hydraulic cylinder, still sketching up the conversion of the cylinders to simulate the braking load points but the piston and cylinder design should make this quite simple as its already designed to take a rod in compression that would normally operate the clutch arm.
Would be very interesting to compare the output of the two sensors in terms of precision, noise, response time etc.

MaX.

Can do once i get set up, they are both internal electronic types and give 0-5v for full range. Noise is not such a concern, the measurement is quasi-static so a simple low pass filter (R-C) would sort this out anyway. The Leo Bodnar board apparently has digital filtering available on the inputs as well but im not sure how this is implemented (review please DD :)

Both units have been fitted with pressure snubbers (to protect against pressure spikes in their original application i guess) and i am trying to work out if i can remove them or open up the port a bit as this will probably slow them down a bit. The actual sensing part is a strain gauge diaphragm so the inherent response time will be much quicker than you can apply the force.

I will have a look at a few vendor sites and see if they quote any typical numbers, the internal constructions will all be very similar so should be good as a guide.

First quote i found...
The standard design of modern pressure transmitters already allows rise times of ≤ 2 ms.

hopefully not too slow  ;)


doubledragoncc

Hi H, yes I will have a complete DIY section. Just because I wish to sell my own controls will not stop me supporting the DIY market, in fact, I am writing the business proposal to Leo Bodnar right at this moment, just popped in to check the forum. I am going to be making components that are very much aimed at the DIY market while still useable in my own systems. This reduces costs and covers both sectors of the market. I am also aiming for the console market for bike games as it is still to do with bike controls and the market is huge.

I will release further detail once I am fully up and running. Its all down to finding the finances right now. I have a full product line to release when I do.

DD
GPBOC Live Streams: https://www.youtube.com/c/IASystemsComputerControls; i7 12700K 5.1GHz Z690 ASUS Strix Z690-A Mobo 32GB 3600MHz DDR4 RAM ASUS Strix RTX3080 OC 10GB DDR6X ASUS Ryujin 360 AOI Cooler ROG Thor 1200w PSU in ROG Helios Tower Case.

HornetMaX

Quote from: h106frp on January 25, 2015, 10:21:43 AM
Quote from: HornetMaX on January 25, 2015, 10:07:42 AM
Quote from: h106frp on January 24, 2015, 05:02:43 PM
Managed to scrounge up a couple of old 100bar pressure transducers - so the hydraulic adapters between the 10mm bike fittings and 12mm landy clutch slaves are going to incorporate a G1/4' pressure tapping which should be quite neat. Have not checked the transducers are working yet so hope they are ok.

As a fall back if the transducers are no good i will use the simple load cell scheme on the hydraulic cylinder, still sketching up the conversion of the cylinders to simulate the braking load points but the piston and cylinder design should make this quite simple as its already designed to take a rod in compression that would normally operate the clutch arm.
Would be very interesting to compare the output of the two sensors in terms of precision, noise, response time etc.

MaX.
First quote i found...
The standard design of modern pressure transmitters already allows rise times of ≤ 2 ms.

Yeah but that is without any filtering I suppose. As soon as you have noise (from the electronics, D/A convertes or from the sensor itself) you start doing filtering and moving averages and your response time suffers.

MaX.

doubledragoncc

I am not sure yet as I am looking for the right transducers at the mo, but I am sure Leo's boards filter most of the problems out. I am actually asking him in this proposal about his boards and transducers. He is real cool when it comes to making small boards to connect other input devices to his boards.

I will let you know asap.

DD
GPBOC Live Streams: https://www.youtube.com/c/IASystemsComputerControls; i7 12700K 5.1GHz Z690 ASUS Strix Z690-A Mobo 32GB 3600MHz DDR4 RAM ASUS Strix RTX3080 OC 10GB DDR6X ASUS Ryujin 360 AOI Cooler ROG Thor 1200w PSU in ROG Helios Tower Case.

h106frp

Quote from: HornetMaX on January 25, 2015, 12:19:04 PM
Quote from: h106frp on January 25, 2015, 10:21:43 AM
Quote from: HornetMaX on January 25, 2015, 10:07:42 AM
Quote from: h106frp on January 24, 2015, 05:02:43 PM
Managed to scrounge up a couple of old 100bar pressure transducers - so the hydraulic adapters between the 10mm bike fittings and 12mm landy clutch slaves are going to incorporate a G1/4' pressure tapping which should be quite neat. Have not checked the transducers are working yet so hope they are ok.

As a fall back if the transducers are no good i will use the simple load cell scheme on the hydraulic cylinder, still sketching up the conversion of the cylinders to simulate the braking load points but the piston and cylinder design should make this quite simple as its already designed to take a rod in compression that would normally operate the clutch arm.
Would be very interesting to compare the output of the two sensors in terms of precision, noise, response time etc.

MaX.
First quote i found...
The standard design of modern pressure transmitters already allows rise times of ≤ 2 ms.

Yeah but that is without any filtering I suppose. As soon as you have noise (from the electronics, D/A convertes or from the sensor itself) you start doing filtering and moving averages and your response time suffers.

MaX.

Having done a lot of this stuff in my real world job i am not too concerned about the noise, the pressures, forces and voltages are high enough to mask out any low level noise issues (often find myself working in microvolt environments). From experience the major source of problems is poor grounding schemes, floating earths etc. This is often overlooked but is probably the most important aspect in getting clean signals. Proper attention to the difference between earthing/drain/grounding and realizing the importance of the various voltage potentials that may exist between what is commonly termed the 'ground' point can often solve what seem puzzling electrical problems.

Warning.... this bit will be of no interest to 99%of readers unless your thinking of building something with multiple power supplies... ::) lol....
Consider the case of USB power from the PC and another source from a wall wart, without checking you cannot guarantee that both will have the same 'ground' potential and currents may circulate between them generating noise voltages. The common one is confusing 0volts with GND or earth, these can easily have a few or maybe even a few hundred volts potential difference and the currents flowing could be significant. Seen equipment destroyed by people attaching grounded mains powered scope probes to the 0 volt point on a piece of equipment without realising the difference in potential - battery powered scopes are better as the low side can 'float' to the equipments ground reference voltage without damage. 

Filtering and amplifying should always be the last option and is often not required if other issues are sorted first.