Relationship between end of crank arm & mounting point on platform

Cool a lot of people still dont treat stuff like that with care if you notice what's in the picture 240v is all exposed only takes a child or a drunken friend to put a finger in the wrong place and they are in a serious way, even if the circuit breaker trips.

eaorobbie,
I can wire a home, but electronics, don't know squat...but yes, I noticed the open exposure on the pic...only assumed it was around the builder - BUT, we never assume around electricity....will get you killed in less than a heartbeat......you and I are on the same page when it comes to electrical power.
Thanks

Agreed, I recently finished a whole frame conversion with shoulders motor mount and he wanted 80mm CTC levers on big worm gears, it was only when I actually showed him that it was too long for the motors to cope that we reverted to 45mm CTC levers. There are plans to make something up to give 200mm throw, but not for a while. Now it has good throw with snappy motion. Once profiles are set right , even a small lever length can feel like 14 inches of throw. All part of the mind trick.

So are we saying that the mounting point on the platform should be directly above the motor shaft? Obviously the angle of the connection rod would depend on the length of the crank arm Like So:



BTW. What is a recommended crank arm length? My platform is going to be used for flight sims only so quick motion is not the main concern.

Thanks

It will depend on what motors you plan to use, design of frame that will determine lever length. If you plan to use a similar design, you are going to need 12v boat winch motors. 24v motors or 240v and the load is higher up than where the lever connects to the frame.
Lever length will need to be calculated depending on how far you want to swing it. For flight, obviously more than race, but take into account the frame design.
As for lever placement, in the pic, I have drawn a red line from where the motor lever should actually sit. Ideally, keep it at a 90 deg angle to the top frame, so its all square. The motor shown in the pic is in the wrong place. I advised that builder ages ago to move the motor so its more level, It worked first go for him.
If I have made a mistake, please advise.
Cheers, Dave.

Dave,

So are you answering yes to my first question? "The mounting point on the platform should be directly above the motor shaft?"

I am going to build the frame from steel. I have a 750kg universal joint and ball joints rated to 320kg each so the frame will be more than capable of handling the weight. Once the frame is built i will then measure the Nm required to turn the crank arm with load on the platform and purchase motors accordingly.

This is not a simple calc mate, Need to take in consideration the torque of the motor but would recommend a lever that has multiple holes on it, save working out all the calcs , but rule of thumb does apply, you can draw it in Sketch Up to test how long a lever is needed for the amount of roll and pitch that is needed. I prefer AutoCad but that's not free and takes a while to build a decent drawing, but I am trained in it. I would work on about 20 deg for all. Any more results in a ridiculous feel once you sitting on top, like the CKAS way too much to feel real, keep your pivot point under the frame as closed to base as possible as the further it is away the forces increase badly. Resulting in loss of motion due to over stressed motors.
And no the top mounting point doesn't need to be above the centre of the motor. Just make sure in the full range of movement , the connecting rods doesn't go vertical ie 90 deg. I like to use 160 deg of rotation for the motor arm movement which results in the connecting rod not equaling vertical.

Rob answered it better than me.