Just some Words to add ..
For those interested in Steadycams , Vest and Arms , you also have " Proaim.be "
https://www.proaim.be/collections/all-s ... er-gimbals ( free advertising .. )
Several Years ago , I have " DIY " .. a Steadycam , and the arms .. it requires some tools and ball bearings .. not perfect , but I learned a lot .. With a simple Diagonal Coil Spring , the reaction is Not perfect .. If you push the camera Up , and let it go , it comes back to the previous level .. same thing if you push it Down .. The perfect Arm is an Iso-Elastic arm .. any place you put the camera on the vertical axis , it remains on the same level .. It is achieved with very strong springs , a steel Cable , and double-stage Pulleys .. The Pro Commercial versions are very expensive Tools .. If I am Energetic enough , maybe one day I'll try to make one by myself ... but a bit difficult to be behind the viewfinder and to build the tools .. a bit much for one man .. I have to be Realistic ..
An interesting solution would be to make a Steadycam , but with an electronic brushless motor control of only the Roll Axis .. so we keep the instinctive and natural action of the Steadycam , and the ease of gimbal control for the roll axis .. large diameter and high Torque brushless motors exist .. perfect for that purpose .. I have used Alexmos boards , they need some work and tuning , but work very well ..
Anyway , when you work Solo , you quickly understand your limitations ( I understand My limitations ... ) , as someone says " Nobody ever made a Film alone " ..
Just my Two Euros .. with my Regards from our Old France ... / Mike ..