While browsing stuff for a LEGO integration project, I came across these compatible Linear Actuators from Firgelli (a Canadian company), what they call "LEGO Actuators"...
They look quite interesting, specially because they are self contained units which include their own electric motor embedded.
The motors must be really small, as per the actuators pictures we see on the respective Firgelli webpage.
Also Firgelli claims for compatibility with both NXT and LEGO Power Functions systems.
Hence these could turn into a useful piece, as an alternative to designing with awkward gears, motors, servos and linkages. This, if you are not a purist, of course... and this the point we return to heavily animated discussions, like in a few posts ago...
Despite never having seen them available for ordering, since the day I've noticed them, they are actually advertised in two sized versions (50 and 100mm stroke lengths), as pictured below.
The use cases, are:
- For use with the NXT Brick you will need a standard NXT connection cable to connect it in place of one of the MINDSTORMS Servos, and you will need to download the respective NXT-G block from Firgelli.
- For manual use with LPF components, you will require an NXT-PF cable available also from Firgelli. The combination of LEGO 8528 NXT converter cable, with one 8886 or 8871 extension wire is also likely to work in my suppositions.
- For manual use with older Technic style battery packs, you will require their NXT-Technic cable, but guess the original one from LEGO (8528) should also work with Firgelli actuators!?
The PF or 9V connections will just drive the actuator motor, wilhe the 6-pin NXT connection will allow for actuator driving and position control.
These "LEGO Actuators" seem to be built based on one of the Firgelli L12 Linear Actuators & Servos, which do exist in several versions (the basic version, one with limit switches, one with position feedback, one with internal position controller or a servo version for RC and robotic applications).
Once I didn't manage to get answers from the manufacturer, just can give my best guess, which goes for the L12-I version (with internal position controller).
From the L12 specs described in the Firgelli datasheet, we can get them in 5-6V or 12V versions, and also with gear reduction ratios like 50, 100 or 210, which correspond respectively to 23, 12 and 5 mm/s maximum speeds (no load condition) at 43, 80 and 150N force. See the datasheet if you are looking for more detailed info, like force and consumption curve characteristics.
Nevertheless it is still unclear, which of these versions is used in their "LEGO Actuators" products.
While the real product doesn't seem to be yet available, we can take a look into another L12 linear actuator in action, from one Firgelli video at YouTube.
I guess the Firgelli webpages about these actuators, aim for an early product announcement/promotion, or have anyone here actually bought them?
Probably it is just a matter of getting final production parts for the specific LEGO compatible plastic cases, which from a few details in the pictures above, look like still in a prototyping phase, at the time they were taken.
Advanced prices at their website, are however quite expressive.