Controlling continuous rotation servos with rc recievers - Page 1
Forum section: electronics / projects

author: robotseth
author_rank: Newbie
timestamp: July 28, 2016, 07:05:03 pm
content: Can you use continuous rotation servos as drive motors for a mini rc robot? I want to control them with a rc remote and receiver. I know you can control normal servos and that the receiver will output pwm.

author: Kilrah
author_rank: Unknown
timestamp: July 28, 2016, 07:37:25 pm
content: Continuous rotation servos are just normal servos with the feedback pot disconnected and mechanical end stops removed, turning them into simple geared motors with a bit of a speed control and forward/reverse capability. Same control interface.

author: robotseth
author_rank: Newbie
timestamp: August 10, 2016, 09:58:29 pm
content: Thanks for the help!

author: Audioguru
author_rank: Super Contributor
timestamp: August 11, 2016, 01:19:35 am
content: The motor in a servo is tiny and has brushes. It is not designed to be running continuously producing power, it opens and closes a CD tray occasionally or drives the propeller of a cheap small RC model airplane or drone for an hour before its brushes wear out. Maybe your robot will not be moving all the time. Brushless motors that last forever are used in better airplanes and drones.

author: rdl
author_rank: Super Contributor
timestamp: August 11, 2016, 02:10:49 am
content: Continuous rotation servos have been used to drive the wheels on small robots for decades. You don't even have to mod one if you don't want to. You can buy them ready to use.Available here and many other places.https://www.parallax.com/product/900-00008

author: CatalinaWOW
author_rank: Super Contributor
timestamp: August 11, 2016, 03:02:04 am
content: Maybe I am just not obsessive enough running my robots, but the motors in my servos haven't succumbed to the horrors of "long" duration operation. But then my application only runs them for a few minutes at a time, much like the model airplane application.

author: robotseth
author_rank: Newbie
timestamp: August 11, 2016, 04:50:42 pm
content: Does anybody know of a cheep (sub $40) rc remote which won't interfere with itself (you can use two in the same room with different robots)?Thanks

author: CatalinaWOW
author_rank: Super Contributor
timestamp: August 11, 2016, 05:32:19 pm
content: Does this meet your needs? Only 33 dollars (not including servos). There are several other inexpensive choices here and elsewhere. As always, low price is not always associated with best service, but I have found the general products of this supplier to be very serviceable.http://www.hobbyking.com/hobbyking/store/__16239__HobbyKing_HK6S_2_4Ghz_FHSS_6Ch_Tx_Rx_Mode_2_.html

author: robotseth
author_rank: Newbie
timestamp: August 11, 2016, 09:35:22 pm
content: Thanks! Can you use two of them in the same room?

author: Kilrah
author_rank: Unknown
timestamp: August 11, 2016, 09:48:44 pm
content: Of course.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: August 11, 2016, 10:21:50 pm
content: Quote from: CatalinaWOW on August 11, 2016, 05:32:19 pmBeat me to it. HK is great, but I recommend1) hovering over items for a few minutes, often HK will offer a reduced price.2) making a large purchase because the shipping can be expensive/slow.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: August 12, 2016, 02:19:44 am
content: Quote from: robotseth on August 11, 2016, 09:35:22 pmThese things are digitally coded and also select or hop around frequencies to allow more than one to be on the air at the same time. I don't know about this system specifically, but there have been some tests that indicate that significant problems occur at rc flying fields with some brands when 40 or more are in use at the same time.This style of radio is also used in indoor flying contests and demonstrations where there are often a dozen or more planes in the air in a space the size of a basketball court.Your robot application may have you in an even smaller room, so receiver overload is a possibility. You can always kill the antenna gain if it turns out to be a problem when you actually try it.

author: robotseth
author_rank: Newbie
timestamp: August 13, 2016, 03:04:40 pm
content: Thanks for the help!

author: robotseth
author_rank: Newbie
timestamp: August 22, 2016, 04:59:46 pm
content: Do any of you know the voltage of the dc power input of that remote?

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: August 23, 2016, 02:38:23 am
content: Quote from: robotseth on August 22, 2016, 04:59:46 pmIn true HK style, you have to navigate their garish web site and figure it out for yourself:

author: Bukurat
author_rank: Regular Contributor
timestamp: August 24, 2016, 12:34:30 am
content: According to the review posts the referenced transmitter uses 8 AA batteries.Quote

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: August 24, 2016, 01:04:46 am
content: Quote from: Bukurat on August 24, 2016, 12:34:30 amHK's site is so awful that the description doesn't tell you what powers the radio, the user manual doesn't tell you, you just keep going through the files until you see that picture... And it looks an awful lot like my 9XR so I figured that must be right. I just now saw the AA battery terminals...In any case, AAs kinda suck. O0