Ohlins electronic suspension spotted

[Robert Taylor]

Ummmmm. The sensors are already very small, light and not very expensive. Computing power likewise is neither here no there since it is reliable, cheap and duable these days.
The trouble is writing the code to get the desired result without spitting the rider into the scenery.

What would you be looking for from an 'active' system as an improvement over a reactive system?
What are the key paramaters they need to be addressed?
Would the added complexity actually translate into speed?

Interestingly the Lotus system developed was a true active suspension with a focus more on ride control than optimising chassis attitude. The Williams AP derived system, by their own admission, was a reactive system but ultimatly the more effective solution

Before entering the discussion be sure that 'active' isn't synomous with 'Holy Grail'

Yeah its interesting comparing the automotive side to motorcycles. With Formual 1 and Indycars etc everything is subservient to aero function and making sure the centre point of pressure doesnt migrate too much.
I think the real issue is not so much the control systems with active suspension, its reading whats ahead. Not so difficult on a closed race course, as was the case with the compound active and reactive Ohlins and WP systems. But a real can of worms on the road, e.g how many ripples are there on the 500metre section of road ahead? What is the profile of each ripple and what velocity would it deflect the suspension at? What is the unit time between each ripple / bump? How much more low speed compression damping is going to be required to stop the chassis g-ing out on the upramp of that hill?
At the back of my mind the systems such as Bose would meet their ultimate challenge on our high proportion of bumpy roads, the same challenges that face our current reactive units.
Its interesting just watching the dynamics of tyre sidewall compression, especially for example if you are following a badly spriung or totally unsprung trailer. With any suspension deflection its actually the tire sidewall that moves first, every brand and type of tire inputs different energies and frequencies into the suspension, something road racers grapple with all the time. Thats another factor of many.
Active will be a holy grail sometime in the future but theres a lot of work to do yet!

[imdying]

Ummmmm. The sensors are already very small, light and not very expensive.

That Bosch linear potentiometer hanging off the fork is about $800 for the cheap model. Does it need to be that precise (read expensive), I don't know...

[cowpoos]

the physics involved are relatively simple and a slow process

No...quite complex physics actually...I thought you would understand that being a pyhsics student and all??...and what sch-cat is saying about rider inputs is the key...you will need alsorts of sensors and a physic ball to predict what the rider will do. minor rider inputs have a large influence on how a bike reacts to anything.

[Robert Taylor]

That Bosch linear potentiometer hanging off the fork is about $800 for the cheap model. Does it need to be that precise (read expensive), I don't know...

Thats of course for the datalogging and it generally has to be military spec to be durable enough. The frequencies that are occuring are also pretty extreme. But given time the real cost of all of this stuff will come down in price, which it needs to!

[bogan]

No...quite complex physics actually...I thought you would understand that being a pyhsics student and all??...and what sch-cat is saying about rider inputs is the key...you will need alsorts of sensors and a physic ball to predict what the rider will do. minor rider inputs have a large influence on how a bike reacts to anything.

"relatively simple" is what I said, have you seen what they done with the su37? yeh, I'd say this is simple in comparison. And I'm a mechatronics grad, not a physics student, cover similar shit though. Would you need to predict the rider inputs though? maintaining the bike in a neutral position regardless of rider inputs could be done as simply as a proportional control system, and add the bump prediction adjustments after that would still provide vast benifits, no braking dive allows later braking into corners etc.

[Robert Taylor]

"relatively simple" is what I said, have you seen what they done with the su37? yeh, I'd say this is simple in comparison. And I'm a mechatronics grad, not a physics student, cover similar shit though. Would you need to predict the rider inputs though? maintaining the bike in a neutral position regardless of rider inputs could be done as simply as a proportional control system, and add the bump prediction adjustments after that would still provide vast benifits, no braking dive allows later braking into corners etc.

I think also there has to be a point that is defined as ''good enough''. Achieving decent ride height and pitch control plus bump compliance in a fast passenger road car is relatively straightforward and you can achieve ''good enough'' easily. But in road racing of bikes we already work within very fine parameters and sometimes frustrating compromise in terms of grip, chassis stability, tyre temperature and life. Racing is certainly the hardest discipline to test new technology and good enough doesnt stay good enough for too long.
Also when I say compromises the new possibilities that mechatronics opens up shows just how much of a compromise current suspension actually is. It will be like having a suspension tuner on board to adjust your clickers at every point of the track, in real time.
How long has the term ''mechatronics'' been coined?

[bogan]

I think also there has to be a point that is defined as ''good enough''. Achieving decent ride height and pitch control plus bump compliance in a fast passenger road car is relatively straightforward and you can achieve ''good enough'' easily. But in road racing of bikes we already work within very fine parameters and sometimes frustrating compromise in terms of grip, chassis stability, tyre temperature and life. Racing is certainly the hardest discipline to test new technology and good enough doesnt stay good enough for too long.
Also when I say compromises the new possibilities that mechatronics opens up shows just how much of a compromise current suspension actually is. It will be like having a suspension tuner on board to adjust your clickers at every point of the track, in real time.
How long has the term ''mechatronics'' been coined?

yeh, it'll certainly be interesting to watch what comes out in the near future, even more interesting if I manage to get amongst it Not sure exactly how long, but massey has been offering a mechatronics major for over 10 years anyway, though robotics majors is essentially the same thing.

[schrodingers cat]

That Bosch linear potentiometer hanging off the fork is about $800 for the cheap model. Does it need to be that precise (read expensive), I don't know...

The sophistication we're talking about here comes at a price premium. A really good data logging system for example can easily have $30 000 dollars sunk into it. At certain levels the belief is they get a benefit from it rather than a $1000 system.
Given the amount of development and the effectiveness/reliabilty from current hydraulic systems I think we're a loooooong way from seeing this stuff on road bikes other than as a marketting hype. The ticket price of a bike compared to a car isn't high enough to absorb the premium pricing required.i.e An 'Active' bike would be a large percentage more expensive than a conventional and realistically - not much different on the road.

RT is right - if the rulemakers allow it a benefit will be extracted but with huge investment. The reason it is banned is due to the current economic climate. A single dominant team/rider/manufacturer is bad for the sport

"relatively simple" is what I said, have you seen what they done with the su37? yeh, I'd say this is simple in comparison. And I'm a mechatronics grad, not a physics student, cover similar shit though. Would you need to predict the rider inputs though? maintaining the bike in a neutral position regardless of rider inputs could be done as simply as a proportional control system, and add the bump prediction adjustments after that would still provide vast benifits, no braking dive allows later braking into corners etc.

Everything is easy when you underestimate the true nature of the problem.

I'm not taking a stab, I just think that you should probably stand off a wee bit and let the warning lights come on. There are obviously a few folks commenting on this thread who know a thing or two and have had an involvement with this sort of stuff

I admire your confidence but assure you the devil is in the detail. As you start to understand exactly what is involved in this challenge you may wish to revise your opinion

[bogan]

Everything is easy when you underestimate the true nature of the problem.

I'm not taking a stab, I just think that you should probably stand off a wee bit and let the warning lights come on. There are obviously a few folks commenting on this thread who know a thing or two and have had an involvement with this sort of stuff

I admire your confidence but assure you the devil is in the detail. As you start to understand exactly what is involved in this challenge you may wish to revise your opinion

and everything is too difficult if you a) don't understand what is possible with todays technology b) believe it's too hard. If you hadn't seen the bose video would you have beleived it was possible to get such and improvement on the bumps over a conventional system?

Also, where the fuck has the kiwi 'give it a go' attitude gone? John Britten was a fucking legend, have attitudes changed so much since then we will never see anyone else get close?

[Pixie]

The Bose and other similiar systems are indeed interesting. Without benefit of intimately studying it Id surmise that currently it is more promising for high performance passenger cars where ride quality and reasonable chassis stabilityare paramount.
If people in MotoGP and WSBK wanted to embrace the technology their very first hurdle would be getting it past the rulemakers and in the current environment I cant see that happening in a hurry.
And then theres packaging on a motorcycle and the power supplies to run it, not insurmountable problems but existing problems nonetheless. ABS systems are an example, they have merit but with weight and bulkiness.
Race bikes require quite specific damping curves for each circuit and many other variables that can be arranged with specific bleed passages, piston designs and shim stack arrangements. At this point I surmise that the Bose system cannot emulate those curves unless someone has studied it in detail and can tell me otherwise.
Certainly its not being currently embraced with open arms by all suspension manufacturers so I am guessing that there are still limitations or issues as described above that it still cannot address, but will with the passage of time and resources. Thats not in any way being skeptical but it still appears that we will have modulating shim stacks for some time ( albeit with electronic aids ) as they still do an excellent job at reasonable cost.
Whichever, the future looks exciting.

The Bose system uses linear motors with the electronics mounted direct on the suspension units.If you look at the picture in the link on post #37,you can see the finned heatsink on the unit.The power requirements are quite low as the units are regenerative -as the bump drives the unit up it generates electrical power that is stored for future use.
Damping functions are provided by controlling the force the motor applies to the wheel -basically if you wanted to, you could stop the upward movement dead,the video showed the system has the power to jump a 2000 kg car off the ground.You could even chock the body and lift the wheel to do a tyre change a la old Citroens.
I guess the software engineers are the guys that do the job of "building shim stacks" and fitting new "springs".

[Robert Taylor]

The Bose system uses linear motors with the electronics mounted direct on the suspension units.If you look at the picture in the link on post #37,you can see the finned heatsink on the unit.The power requirements are quite low as the units are regenerative -as the bump drives the unit up it generates electrical power that is stored for future use.
Damping functions are provided by controlling the force the motor applies to the wheel -basically if you wanted to, you could stop the upward movement dead,the video showed the system has the power to jump a 2000 kg car off the ground.You could even chock the body and lift the wheel to do a tyre change a la old Citroens.
I guess the software engineers are the guys that do the job of "building shim stacks" and fitting new "springs".

Its pretty clever alright. Pardon the bad pun but theres a few bumps along the way though with any new applications of technology, including but not restricted to further development, packaging for varying installations and that old bogey, price