Intelligent motion control blog

Published: 08.11.2011

The NorrDigiTM intelligent fluid condition management

The NorrDigi™ intelligent fluid control management provides not only improved filtration of the hydraulic system during operation, but also a unique feature: the complete flushing of the hydraulic system on demand or automatically, after the service operation or during startup. No additional pipes, hoses, or valves are needed.

With NorrDigi™ intelligent fluid control management, the existing filtration solution of a machine can be used – with the help of the common pressure rail – to clean all the oil capacity. The filtration process for the accumulators and common pressure rail can even be carried out while holding a load.

New features of the NorrDigi™ intelligent fluid condition management

• No need for any add-on hydraulic flushing equipment for hydraulic system filtration. Only the basic NorrDigi™ product platform with common pressure rail is needed.
• Needs only the common return filter of an existing hydraulic system.
• The integrated control valves of actuators can be used for controlling flushing flow.

The NorrDigi™ intelligent fluid condition management is based on – and always automatically included in – the standard NorrDigi™ product platform.

Main benefits of the NorrDigi™ intelligent fluid condition management

• After each service operation or during startup, flushing can be set to run automatically.
• Filtration class improved compared to existing systems.
• Extended lifetime for components.
• When trouble shooting, single damaged components can be found using the filtration process.

The NorrDigi™ intelligent motion control solution does not need an improved filtration class for the oil, but it can provide it.

Published: 04.11.2011

Progress in many areas

As the tough finnish nature begins to show its colder and darker side after another hot and bright summer, a lot has happened in the NorrDigi™ world since the last update of this blog.

First of all, Norrhydro product development has moved to new and bigger facilities in Tampere. The new address is Niittyhaankatu 9, FI-33720 Tampere.

In the technical side, very interesting news will follow shortly.

Published: 30.06.2011

Different digital hydraulic technologies

People often ask us, how big ownership does Norrhydro have over NorrDigi™. The answer is 100%. We are well aware of other digital hydraulic technologies – as most of them rise from Tampere – but we believe that our solution is very competitive for working machines.

Another question we keep hearing, is the availability rate for the components needed for the NorrDigi™ technology, especially valves. For a short answer, look at these videos: 1. Energy recycling, 2. Power consumption in loading. They show, that the NorrDigi™ technology works well with commercial valves, and in fact, it provides very good controllability and energy efficiency for working machines.

Published: 29.06.2011

The science behind NorrDigiTM

We have uploaded the one and only scientific publication of NorrDigi™ in our webpage. This paper describes the basics and the very beginning of the technology. The work for this paper was carried out mostly before the year 2009 and the paper was published in SICFP’09 in Linköping Sweden. The conference organizer holds the copyrights to this paper.

All further developments to the technology, carried out by the NorrDigi™ development team since the beginning of 2009, have been remained scientifically unpublished. But since the sell rate of the multichamber cylinder is growing, the technology seams to speak for itself.

Published: 09.06.2011

Energy efficiency that surprises

As the weather forecast predicts about 27 C to Finland for the whole week, it reminds us about a funny event from last summer.

As you may know, NorrDigi™ provides very energy efficient control at all times: under heavy or light load, with heavy or low cycling, and in warm or cold weather. Thus, in many applications the coolers become almost unnecessary after NorrDigi™ has been applied to the system. Last summer, during the first tests of our forest machine forwarder, we got into a problem of having a too low oil temperature. We even started to look for heating devices before we realized, that producing heat with hydraulic systems is an old invention. On the other hand, producing force instead of heat is relatively new invention, and it is called NorrDigi™.

 NorrDigi™ development team

Published: 24.05.2011

Basic physics in lifting business

Why do we think NorrDigi™ is so great? Well, here is something about the basic physics in lifting business.

Imagine a working machine with an operation cycle of lifting and lowering certain mass repeatedly in cycles. According to basic physics, this kind of action should not consume any energy, except for only minor friction losses. This is because the potential energy needed in lifting a load is recovered when lowering the same load. However, if this kind of operation is done with traditional load sensing hydraulic technology, the energy losses are clearly not minor.

One might say that lifting and lowering the same mass between two positions is hardly interesting to anyone. So, how about if we lift a certain mass from its initial position to a higher level. For example, lift logs from ground and place them to the load space using the boom of a forest crane.

Here is an example of a simple loading cycle:

• Phase 1, the load mass is lifted with the boom from the ground to a height of 4 meters to overpass the walls of the load space.
• Phase 2, the load mass is lowered to a height of 2 meters inside the load space, and then logs are dropped to load space.
• Phase 3, the boom is lifted to 4 meters to overpass the walls of the load space again.
• Phase 4, the boom is finally returned to ground.

In this working cycle the needed energy is in theory only the potential energy of lifting the load mass to the height of 2 meters, since everything else is recovered in lowering actions.  However, if this kind of operation is done with traditional hydraulic technology, the energy losses are clearly much more than just that.

The two attached figures describe the changes in potential energy, energy consumption of traditional hydraulics, and energy consumption of NorrDigi™ (upper figure) as well as the energy losses of both systems (lower figure). The load mass in these computations was 500 kg. Note that only simple lifting cycle is taken into account in this example. If, for example, the swing would be taken into account, in NorrDigi™ system the energy used in accelerating the booms angular velocity could be restored when decelerating, while in traditional system not.

We here at Norrhydro believe that we have a way to make the booms for many applications well controlled, robust, fault tolerant, and above all, as energy efficient as possible. The way to do this is the NorrDigi™ way.

NorrDigi™ development team

Published: 19.05.2011

New blog published

Here at Norrhydro, we have launched a blog about the interesting world of NorrDigi™ technology and anything related to it.

SICFP’11 is here at Tampere until Friday, the 20th of May. Three days of interesting presentations and discussions offer us a fertile soil to create future innovations. However, one very interesting innovation is already here: NorrDigi™, the intelligent motion control system by Norrhydro is available today.

NorrDigi™ development team