Servos - Revision history

Chklnk: Rewrite of how-to

2023-11-26T23:59:30Z

Rewrite of how-to

Chklnk: Chklnk moved page Servo to Servos: Plural is consistent with other topics

2021-05-25T06:10:33Z

Chklnk moved page Servo to Servos: Plural is consistent with other topics

Chklnk: Slight wording change

2021-05-25T06:09:32Z

Slight wording change

Chklnk: More selection factors and link to SDB

2021-05-25T03:59:14Z

Chklnk: New stub article, needs photos, details

2021-05-25T03:48:10Z

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New page

Combat robots use servomotors as actuators, positioning devices, and sometimes as drive motors. These servos are the same type used in [https://en.wikipedia.org/wiki/Servo_(radio_control) remote-controlled devices] such as model aircraft, boats and cars, as well as other hobbies. Most common radio-control receivers have connections for several servos, allowing them to be directly operated by the controls on the transmitter with very little setup.

These devices take a pulsed electrical signal (usually PWM, or [https://en.wikipedia.org/wiki/Pulse-width_modulation Pulse-width modulation]), and respond by moving a lever, slide, or shaft to a specific position. This motion is usually over a range of rotation such as 90° or 180°.

=How to select a servo=
In combat robotics, the limiting factors for servos are weight, voltage, torque, and cost.

A very durable servo with metal gears may be far too heavy for a small bot

Servos are usually powered by 5 volts from the receiver (instead of directly from battery voltage). The receiver might need a battery eliminator (BEC) module that generates enough power to run both the receiver and all the servo(s).

=How to connect and use=
Nearly all servos have a common type of 3-wire connector, although the wire colors vary:
*Ground wire – Black (or Brown)
*DC power wire – Red (or Orange)
*Signal wire – White (or Yellow)

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 In combat robotics, limiting factors for servos are weight, voltage, torque, and cost. For each servo you plan to use, obtain a specification sheet to find out whether it is suitable for the purpose.
-*'''Weight:''' A very durable servo with metal gears may be far too heavy for a small bot, but one with plastic gears may break quickly when the bot is struck or dropped.
+[https://servodatabase.com/ ServoDatabase.com] lists specifications for thousands of models.
-*'''Voltage:''' Many small hobby servos run on a limited range of voltages, often 4.8~6.0 volts. If your servo can't run directly from your bot's battery voltage, the receiver might need a battery eliminator circuit (BEC) module that generates enough power to run both the receiver and the servo(s).
-*'''Torque:''' Usually stated in kg-cm or ounce-inches. The servo needs to have enough strength to accomplish its task in the bot.
+===Weight===
-*'''Cost:''' High quality servos cost more.
+In combat robotics servos with metal gears are common, because ones with plastic gears may break too easily when the bot is struck or thrown. Plastic-gear servos are most likely to be found on bots in weight classes lower than 150g.
-In addition, here are some other factors you should consider.
+===Torque===
 *Dimensions and mounting method
 *Rotational speed and response time
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 *Availability (you will want to have spares on hand in case of damage)
 *Continuous rotation ability (be careful not to order one of these if you need only a short range of motion)
 =How to connect and use=

← Older revision		Revision as of 06:09, 25 May 2021
Line 1:		Line 1:
−	Combat robots use servomotors as actuators, positioning devices, and sometimes as drive motors. These servos are the same type used in [https://en.wikipedia.org/wiki/Servo_(radio_control) remote-controlled devices] such as model aircraft flight control surfaces, ~~steering for~~ boats and cars, as well as other hobbies. Most common radio-control receivers have built-in connections for several servos, allowing them to be remotely operated by moving the controls on the transmitter with very little setup required.	+	Combat robots use servomotors as actuators, positioning devices, and sometimes as drive motors. These servos are the same type used in [https://en.wikipedia.org/wiki/Servo_(radio_control) remote-controlled devices] such as model aircraft (to move flight control surfaces), boats and cars (for steering), as well as other hobbies. Most common radio-control receivers have built-in connections for several servos, allowing them to be remotely operated by moving the controls on the transmitter with very little setup required.

	These devices take a pulsed electrical signal (usually PWM, or [https://en.wikipedia.org/wiki/Pulse-width_modulation Pulse-width modulation]), and respond by moving a lever, slide, or shaft to a specific position. This motion is usually over a range of rotation such as 90° or 180°. This motion can be used to operate flippers, lifters, self-righting mechanisms, and other features of the bot.		These devices take a pulsed electrical signal (usually PWM, or [https://en.wikipedia.org/wiki/Pulse-width_modulation Pulse-width modulation]), and respond by moving a lever, slide, or shaft to a specific position. This motion is usually over a range of rotation such as 90° or 180°. This motion can be used to operate flippers, lifters, self-righting mechanisms, and other features of the bot.

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-Combat robots use servomotors as actuators, positioning devices, and sometimes as drive motors. These servos are the same type used in [https://en.wikipedia.org/wiki/Servo_(radio_control) remote-controlled devices] such as model aircraft flight control surfaces, steering for boats and cars, as well as other hobbies. Most common radio-control receivers have built-in connections for several servos, allowing them to be directly operated by the controls on the transmitter with very little setup.
+Combat robots use servomotors as actuators, positioning devices, and sometimes as drive motors. These servos are the same type used in [https://en.wikipedia.org/wiki/Servo_(radio_control) remote-controlled devices] such as model aircraft flight control surfaces, steering for boats and cars, as well as other hobbies. Most common radio-control receivers have built-in connections for several servos, allowing them to be remotely operated by moving the controls on the transmitter with very little setup required.
 These devices take a pulsed electrical signal (usually PWM, or [https://en.wikipedia.org/wiki/Pulse-width_modulation Pulse-width modulation]), and respond by moving a lever, slide, or shaft to a specific position. This motion is usually over a range of rotation such as 90° or 180°. This motion can be used to operate flippers, lifters, self-righting mechanisms, and other features of the bot.
@@ Line 8: / Line 8: @@
 *'''Weight:''' A very durable servo with metal gears may be far too heavy for a small bot, but one with plastic gears may break quickly when the bot is struck or dropped.
 *'''Voltage:''' Many small hobby servos run on a limited range of voltages, often 4.8~6.0 volts. If your servo can't run directly from your bot's battery voltage, the receiver might need a battery eliminator circuit (BEC) module that generates enough power to run both the receiver and the servo(s).
-*'''Torque:''' The servo needs to have enough strength to accomplish its task in the bot.
+*'''Torque:''' Usually stated in kg-cm or ounce-inches. The servo needs to have enough strength to accomplish its task in the bot.
 *'''Cost:''' High quality servos cost more.
-In addition, some servos have a "continuous rotation" ability, which allows them to substitute for motors without the need for a motor speed controller. Be careful not to order one of these if you need only a short range of motion.
+In addition, here are some other factors you should consider.
 =How to connect and use=

← Older revision	Revision as of 06:10, 25 May 2021
(No difference)