DIGTAL VS ANALOG servos
10-07-2006, 02:24 PM
#2
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RE: DIGTAL VS ANALOG servos
Digital servos have:
- slightly higher torque for a given motor/gearset (many manufacturers offer the same gearset/motor with a digital or an analog amp -- ie: the Hitec 645 (analog) and 5645 (digital).
- greater holding power. This means that it's harder to deflect the servo away from the commanded position by applying force to the servo-arm. This means you're less likely to get the control surfaces being blown-back by the air flowing over them.
- better centering and accuracy. This is because smaller differences between the actual arm position and the commanded arm position produce larger amounts of torque to correct the difference.
- Hitec's digital servos are programmable (if you have their really expensive programmer). This means you can do all sorts of useful things such as: reverse servo direction, change the maximum throw, set a failsafe position, vary the speed, vary the deadband -- all with just the push of a button or two.
The next question has to be "are digital servos worth the extra money?"
Well I still buy more analog servos than digital ones.
For your average sport plane, regular servos are just fine. They'll provide more speed, accuracy and holding power than you're going to need so the extra money you'd spend on digital servos is better spent on fuel.
However, if you're flying jets, aerobatics or very large planes then you'll find the benefits of a digital servo to be more apparent and worth paying for.
- slightly higher torque for a given motor/gearset (many manufacturers offer the same gearset/motor with a digital or an analog amp -- ie: the Hitec 645 (analog) and 5645 (digital).
- greater holding power. This means that it's harder to deflect the servo away from the commanded position by applying force to the servo-arm. This means you're less likely to get the control surfaces being blown-back by the air flowing over them.
- better centering and accuracy. This is because smaller differences between the actual arm position and the commanded arm position produce larger amounts of torque to correct the difference.
- Hitec's digital servos are programmable (if you have their really expensive programmer). This means you can do all sorts of useful things such as: reverse servo direction, change the maximum throw, set a failsafe position, vary the speed, vary the deadband -- all with just the push of a button or two.
The next question has to be "are digital servos worth the extra money?"
Well I still buy more analog servos than digital ones.
For your average sport plane, regular servos are just fine. They'll provide more speed, accuracy and holding power than you're going to need so the extra money you'd spend on digital servos is better spent on fuel.
However, if you're flying jets, aerobatics or very large planes then you'll find the benefits of a digital servo to be more apparent and worth paying for.
10-07-2006, 04:07 PM
#4
RE: DIGTAL VS ANALOG servos
http://www.futaba-rc.com/servos/digitalservos.pdf
There's a pdf that explains alot about them.
Depends on the application as to whether or not you benefit from them.
There's a pdf that explains alot about them.
Depends on the application as to whether or not you benefit from them.
10-16-2006, 09:23 AM
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RE: DIGTAL VS ANALOG servos
Hi
To test this issues i have buy a servo tester on www.rc-devices.com that let me test the servo on a workbench telling me amount of energy they are wasting while they are working and i have not found significants diferences between Futaba servos and low cost servos, Can anyone cofirm this??.
To test this issues i have buy a servo tester on www.rc-devices.com that let me test the servo on a workbench telling me amount of energy they are wasting while they are working and i have not found significants diferences between Futaba servos and low cost servos, Can anyone cofirm this??.
