It looks like the shutter spring winder has been removed.
I'm referring to the middle shaft with three concentric cylindrical diameters. I'll call it the shutter 'drive shaft' because I don't know what it's actually called.
To the left of that, the rotary lever with the spring operates the retard mechanism. The degree to which it is rotated from the inward spring-retracted position determines the (slower) variable speeds possible in a normal complete shutter.
With the shutter spring absent, and the retard lever pulled all the way in the opposite direction and held there, the torque required to open the shutter is at its minimum. With those actions taken, you should be able to easily rotate the triple-diameter shaft half a turn to open the 4-blade shutter fully, or at least 95%. Some seem to rely on velocity to overshoot the blade opening on the way to reversing direction.
In that condition, I found with a Torq-Watch that only 0.5-1 oz.-in was required on one Fairchild K-17 specimen I have.
In comparison, a K-18 with 24" Aero-Ektar that has a much larger shutter with more blades, and a different design, a maximum of 9 oz.-in. was needed. On that shutter the retard mechanism is operated by a plunger. With it fully depressed, closed-open-closed motion was accomplished with a full rotation of the 'drive shaft'.
On the K-18, there are a couple ways to make it cycle, one with the double-notched shaft which originally was the shutter firing (discharging) actuator, and without. I was trying to find the simplest way with minimal substitute linkage involvement (without the original motors). IIRC, the K-18 can operate with unidirectional rotation.
In the pictured-here K-17, the simplest least-energy way to make it 'work' is half a rotation to open the shutter, and half a rotation in the opposite direction to close the shutter, without using the slotted firing/discharging shaft.
I am going to try some motor drive ideas with vibration control, now that I (recently) figured out the minimum torque (for smallest motor) for both shutter types.
Years go I met an engineer who worked at Recon Optical and asked him about shutter vibration on these kinds of shutters. Hearing a normally-sprung shutter fire is a memorable experience. Makes you wonder how much vibration there is. He said it can vibrate all it wants at the start and finish, but has to be damped during the open portion of the cycle. The mass of the whole camera and what that's bolted to has some role in this.
So the motorized idea may have inherent problems, but I'm not aiming for 1/100 second or less. Just a way to open (T) the lens remotely to focus, (-T) to close, and a open/close operation (call it +T and -T). (T being an analogy to T on small camera shutters)
Alternately, shafts possibly with flex-couplings could bring access to the actuators outside the dark chamber. Non-collinear drive could produce another disturbance, so I'm trying a motor concentric with the drive shaft.
A fairly large lens board is still needed for the 6" Metrogon if retaining the shutter & iris, and not much metal can be removed from the overall dimensions. So a box camera might be easier than a bellows camera.
