I thought that maybe I should share my build of linear actuator, which is planned to be part of a hexapod. It has a 1050mm stroke and is 1500mm long retracted, but I think I can cut it down to 1400mm at least. It should have a max speed of at least 600mm/s (maybe will get it up to 800mm/s) and be able to lift about 100kg.
My goal is to use as few custom machined parts as possible and be able to use industry standard parts to the greatest extent. An other design goal was to make it easy to machine the parts in a way that the errors/backlash of the mill affect the tolerances/alignment in a minimal way.
The parts I’ve used this far:
Odrive dual shaft motor D6374 150kv
CUI 8192 CPR encoder
Square aluminium tube 80x80x3x1500mm
SFU2010 1200mm ballscrew with custom end machining
Carbon fibre tube 36mm ID 40mm OD 1200mm
Aluminium tube 40mm ID 48mm OD 80mm (used for distance/alignment)
2 Conical roller bearings
2 Skateboard bearings
Rigid 10mm coupling
A couple of slabs of aluminium to machine.
Filament for 3d printed parts (such as temporary bruchings, encoder mount, temporary ballscrew nut carrier)
A huge universal joint
An assortment of screws
(planned 60mm server fan for cooling)
(For control I’m planning to use step/dir output from a Beagleboard X15 with machinekit. It needs a bit more tinkering. If someone wanna help out/do a joint project to make this x15 as wonderful of a controller as I know it could be please contact me )
(Also a future plan is to build an interferometer to calibrate for imperfections of the ball-screw pitch and measure precision. )
Right now I have the issue that I cant max out the performance of the actuator because I get ERROR_CURRENT_SENSE_SATURATION, more information of this issue: https://discourse.odriverobotics.com/t/error-brake-current-out-of-range-error-at-high-speeds/1182, which has led me to put the project on hold until the issue is resolved.
The first actuator(prototype) :
Misstakes were made… (adaptor ring!!!)
Forgot to touch off Z…