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How To Build a Robot

Revision as of 20:57, 24 September 2020 by Arthur (talk | contribs) (→‎Chain or belt drive motors to wheels:)

https://www.superdroidrobots.com/shop/custom.aspx/how-to-build-a-robot/70/

General Robot Building Questions | The Big Picture

Building your own robot can be a fun and exciting experience. It can be a little frustrating though when you are not sure about a certain aspect of the build. This is a step by step guide that will help you get your robot up and running. We will go over some robot basics, help you with your part selection, and give you some assembly advice. To get started use our Custom Robot Request Page as a guide with the questions it contains to get a good idea of what kind of robot you want to build. You may also submit the form if you would like to skip the DIY and have SuperDroid Robots and its professional staff build it for you.

Some questions you will want to ask yourself

  • What is my budget?
  • What is my schedule?
  • What do I want the robot to do?
  • What type of terrain will it be used on?
  • Do I have any size requirements or restrictions?
  • Do I have any weight requirements or restrictions?
  • Do I want it to be weather resistant? Weatherproof? Waterproof?
  • Do I have any additional capacity requirements for volume and/or weight?
  • How do I want to control it? Wireless, tethered, Autonomous, RC, WiFi, Fiber Optics, IR, etc.
  • How long of a run time will I need? Will it be run continuously or intermittently during this time? (ie duty cycle)
  • Do I want to build using just parts, a kit, or a completely assembled Ready-to-Run (RTR) Robot?

The basics of our robot kits

Our robot kits are designed based on years of experience designing standard and custom robots. All the components are designed to work together. If you do not have much experience building robots, it is best to start with one of our kits. If you go at it from scratch, it can be done, but sizing motors, wheels, batteries, etc. comes from a lot of experience and trial and error. All of our robot kits have options listed at the bottom of the page allowing you to customize the robot. Standard items and options are selected for a default configuration. The options are listed as links and can be clicked to view further details. We offer many different motors, motor controllers, batteries, etc. so you can configure the robot to your exact needs. The weight of the robot, its capacity, speed, etc. depending on how the robot is configured. You will have to click on the option item details to determine weights, sizes, etc.

Most of our robot kits can be purchased in kit form or assembled. Typically, the kits are offered unassembled as an option. If you have never built a robot, done much soldering or mechanical assembly we recommend you opt for us to assemble it for you. Besides the expert assembly, we will test it, if anything is not right (such as a defective motor or motor controller, battery charger, etc.) we will replace it and make sure everything is ready to run when you receive it.

How does a robot turn?

Most of our robot platforms are skid steer robots (left and right wheels are slowed down, stopped or reversed to turn). Since it has to skid to steer, friction is the major contributing factor for sizing your components. The more the robot weighs, the harder it is to turn. The higher the friction coefficient (deep grass, carpet, tracks, etc.), the harder it is to turn. The lower RPM motors have lower speed, but more torque for easier turning. The default options listed for our robot kits are what we recommend as a good starting point. Contact us if you need help selecting options or need custom configuration.

Let's Get Started!

There are a lot of decisions that need to be made once the general questions are answered. Most of this information is in order. In some cases you can jump around, but basically you cant pick your batteries, until you know what your motors are, and you cant pick motors until you pick a platform, etc.

Tracks or Wheels?

Tracks

Everyone thinks tracks are cool. They are, but they come with complication and price.

Tracks add many advantages:

  • Spread your load out for a low PSI rating.
  • Makes climbing and bridging over gaps, such as stairs, etc. much easier.
  • Handles more aggressive terrain, etc.

They also offer a lot of challenges:

  • Less efficient (use more power, larger motors, etc.).
  • Components are more expensive.
  • Tracking, derailment, tensioning, etc. all must be considered.
  • Debris jamming the tracks, etc. needs to be considered.

We offer many pre-made tracks:

  • [##CATEGORY161## Treads and Tracks]

We offer many DIY tracks:

  • [##CATEGORY162##DIY Tracks and Treads]

And Treaded Robot Kits that are ready to go:

  • [##CATEGORY73## Treaded Robot Kits]

Pictures

If you are ready to move forward with a tracked robot

You have to consider everything you want out of the chassis, add some room for modification, feature creep, and then add some more. These are things we have learned by building hundreds of custom tracked robot platforms.

Our LT2 and HD2 tracked robot platforms use roller chain to connect the motor to the drive wheel of the tracks. There are other ways of transferring the power from the motor to the ground but for flexibility, durability, and reliability we use roller chain. If you build a robot platform and discover the motors are not powerful enough, too fast, too slow, etc, simply change the number of teeth on your sprockets.

Our LT2 robot, or Light Tank rev2 uses number 25 chain and two IG52 motors, one per track. The 52 means the gearbox is 52 mm in diameter. We power the front two wheels and the back two are idlers. We also offer the LT2-F with flipper arms.

Our HD2 robot, or Heavy Duty Tank rev 2 uses number 35 chain and 4 IG52 motors, one per wheel. All four are driven. They are supported on both sides with roller bearings for a super solid chassis.

Select one of our tracked robot packages:

  • [##ITEM2364## SST Robot Platform]. The SST Robot Platform is a smaller version of our [##ITEM1513## LT2] and [##ITEM789## HD2] tanks, but built with the same high level of quality, strength, power, etc.
  • [##ITEM1723## MLT-JR Tracked Robot Platform]. Our MLT-JR platform is based on our MLT - Jack Russel Tactical Robot and features the same tracks and similar heavy-duty chassis and drive system. You have your choice of motors, batteries, and controls to get you going!
  • [##ITEM2288## MLT-42 Tracked Robot Platform]. This is a MLT-JR tracked robot platform and is equipped with 32mm motors, a motor controller, and Spektrum remote control. This is a rugged robot platform. By default, the treaded robot handles up to 15lbs of additional payload and travels 300ft/min.
  • [##ITEM2341## MLT-42-F Tracked Robot Platform]. This is a MLT-42-F tracked robot platform and is equipped with flipper arms, 42mm motors, a motor controller, and Spektrum remote control. This rugged robot platform the treaded robot handles up to 15lbs of additional payload and travels 200ft/min.
  • [##ITEM1513## LT2 Tracked ATR Robot Platform]. This platform is a subset of our LT2/LT2-F Bloodhound - Light Surveillance Robot and is one of our NIST qualified tactical robots. The LT2 ATR platform comes standard with the same track system, similar heavy duty aluminum chassis, and your choice of motors, motor controller and batteries.
  • [##ITEM1520## LT2-F Tracked ATR Robot Platform]. This is the same package as the LT2 above, but with the addition of a flipper / stabilizer arm that allows the robot to overcome taller obstacles and enables stair climbing.
  • [##ITEM789## HD2 Treaded ATR Tank Robot Platform]. Likewise with the MLT-JR and LT2 platforms above, our HD2 platform is a derivative of our HD2-S Doberman - Heavy Duty Surveillance Robot. This powerful treaded kit gives you added ability to haul heavier equipment, scale tougher terrain, and climb stairs without the need of an additional flipper/stabilizer arms.
For more information on tracked robots, see our HD2 Support, LT2 Support, and MLT-JR Support pages.

Wheels

Wheels are by far an easier and less expensive option than tracks.

Wheeled robots have a lot of advantages:

  • Easy to use.
  • Low maintenance costs.
  • Lower cost than tracks.

Some of the disadvantages of wheels:

  • High centering when going over uneven terrain.
  • Can't climb stairs without making radical suspensions, etc.

We offer many wheel, and wheel and shaft parts:

  • [##CATEGORY16## Wheels and Shafts Category]
  • [##CATEGORY198## Wheel and Shafts Sets]
  • [##CATEGORY153## All Terrain Robot Wheels and Shaft Sets]
  • [##CATEGORY156## Omni and Mecanum Wheels and Hubs]
  • [##CATEGORY155## Casters]
  • [##CATEGORY154## Wheels for Servos and Miniature Wheels]

We also offer ready-made wheeled platforms:

  • [##CATEGORY51## Wheeled Robot Platform Kits]

And omni-wheel robot platforms:

  • [[##CATEGORY61## Omni Wheel Robot Platform Kits]

To learn more about wheeled robots see our support pages:

Picture

Wheel Types

Before you decide on the platform, there is another fork in the road with wheeled robots. Do you want to use standard wheels, Omni wheels, or Mecanum wheels?

Standard Wheels:

  • Robot Drive Wheel - Traction Lug 13 x 5.00-6 Tiller Tire
  • Robot Drive Wheel - Traction Lug 10 x 3.50-4 Tiller Tire
  • Robot Drive Wheel - 6 inch pneumatic tire
  • Robot Drive Wheel - 10 inch Pneumatic
  • All of these wheels can be configured with shaft sets to fit our wheeled robot platforms. Using standard wheels is the simplest method to move your robot.
  • See all of our wheel sets here.
  • More information can be found on our All Terrain Mobile Robots - Help and Information Support Page.

Omni Wheels - Vectoring:

  • Omni Wheels are round wheels with small wheels built into them to allow lateral movement. This feature makes it great for skid steering. There is very little resistance to make a turn, allowing you to load up your robot. The disadvantage to these wheels is that they make a good deal of noise when rolling around, and they are not good for rough or dirty terrain. They will also side slip if put sideways on a hill.
  • See all of our omni wheel sets here.
  • For more information visit our support pages:
    • Omni-directional 4WD and 3WD Robot Kits.
    • All Terrain Mobile Robots - Help and Information.
    • Vectoring Robots - Help and Information.

Mecanum Wheels:

  • Mecanum wheels are round wheels with small wheels/rollers built into them at an angle. This gives the same effect as Omni wheels mounted on angles, only the wheels are pointed straight ahead, making the vectoring and standard driving a lot easier. These wheels have the same downside as Omni wheels in that they cannot handle a dirty environment very well, and they make a fair amount of noise when rolling around.
  • See all of our wheel sets here.
  • For more information visit our support pages:
    • Mecanum Wheel Robot Kits.
    • All Terrain Mobile Robots - Help and Information.
    • Vectoring Robots - Help and Information.

If you are ready to move forward with standard wheels:

Pictures

Select one of our wheeled robot platform kits:

  • [##ITEM2795## WC1000-DM4-E, 4WD All Terrain Robot Enclosed Platform] This is an SDR 4-wheel drive remote control robot kit. It uses four powerful wheelchair motors and 35AH batteries.
  • [##ITEM2114## IG32-SB2, 2WD Tube Mount Robot Platform] This robot kit consists of the 2WD robot chassis and provides all the necessary parts to turn the robot chassis into an operational robot. This supports our IG32 planetary gear motors.
  • [##ITEM2083## IG42-DB2, 2WD Mobile Robot Platform] This robot kit consists of the 2WD robot chassis and provides all the necessary parts to turn the robot chassis into a operational robot. The chassis will support our IG42 planetary gear motors.
  • [##ITEM1930## IG32-DM4, 4WD All Terrain Robot Platform] This Compact 4WD wheeled robot platform is equipped with 32mm motors, a motor controller, and Spektrum remote control. With the default configuration, the robot handles up to 5lbs of additional payload and travels 298 ft/min.
  • [##ITEM1648## IG52-DB4, 4WD All Terrain Heavy Duty Robot Platform] This is our Heavy-Duty All-Terrain Robot platform with 52mm gear motors, built to navigate through rough terrain and over small obstructions. This heavy-duty robot is configurable.
  • [##ITEM1492## IG42-SB4-E, 4WD All Terrain Enclosed Robot Platform] This 4WD wheeled enclosed robot is equipped with 42mm motors, a motor controller, 10-inch tires, and Spektrum remote control. By default, the robot handles up to 20lbs of additional payload and travels 320 ft/min.
  • [##ITEM1478## IG42-DB4-E, 4WD All Terrain Enclosed Heavy Duty Robot Platform] This is our Enclosed Heavy Duty All-Terrain Mobile Robot Platform. Perfect for outdoor mobile surveillance and object detection, this robot is configurable to meet your requirements. This item replaces TP-080-000, TP-081-000, & TP-180-000.
  • [##ITEM1477## IG42-DB4, 4WD All Terrain Heavy Duty Robot Platform] This is our Heavy-Duty All-Terrain Robot platform with 42mm gear motors. Built to navigate through rough terrain and over small obstructions, this heavy-duty robot is configurable. This item replaces TP-070-000, TP-071-000, and TP-170-000.
  • [##ITEM1474## IG42-SB4, 4WD All Terrain Robot Platform] This 4WD wheeled robot platform is equipped with 42mm motors, a motor controller, and Spektrum remote control. By default, the robot handles up to 25lbs of additional payload and travels 400 ft/min. This robot replaces TP-032-042 and TP-033-042.
  • [##ITEM1473## IG32-SB4, 4WD All Terrain Robot Platform] This 4WD wheeled robot platform is equipped with 32mm motors, a motor controller, and Spektrum remote control. By default, the robot handles up to 15lbs of additional payload and travels 300 ft/min. This robot replaces TP-032-032 and TP-033-032.
  • [##ITEM2809## IG52-SB4-T, Custom Size 4WD All Terrain Robot] This is 2.5" x 2.5" Aluminum tube with a 1/8" thick wall. We machine it to a custom length. Using two of these you can make your custom-sized robot for IG52 motors.
  • [##ITEM2804## IG42-SB4-T, Custom Size 4WD All Terrain Robot] This is 2" x 2" Aluminum tube with a 1/8" thick wall. We machine it to a custom length. Using these you can make your own custom sized robot.
For more information on wheeled robots, see our  All Terrain Mobile Robots - Help and Information.

If you are ready to move forward with vectoring wheels:

Pictures

Select one of our vector wheel robot packages:

  • [##ITEM2346## NEW Prebuilt Mecanum Wheel Vectoring Robot] - IG32 SB This is a direct drive 4WD base Programmable robot kit that uses Nexus mecanum wheels and hubs. This robot platform is meant for indoor robotics. It can vector in any direction. It makes a great Autonomous Robot.
  • [##ITEM2458## Mecanum Wheel Vectoring Robot Kit - IG42 DB] This is a chain-driven 4WD base robot kit that uses Nexus mecanum wheels and hubs. It can vector in any direction making it a great Autonomous Robot.
  • [##ITEM1713## Programmable Mecanum Omni-Directional Vectoring Robot Kit - IG32 SB] This is a robot that utilizes 4 Omni wheels to vector it in any direction. By changing the speeds and directions of the motors the robot can drive in any direction without needing to turn.
  • [##ITEM2229## Programmable Tri-Wheel Vectoring Robot Kit - IG32] Medium Duty SB This is a larger IG32 gear motor robot that utilizes three Omni-wheels to vector it in any direction. By changing the speeds and directions of the motors the robot can drive in any direction without needing to turn.
  • [##ITEM1788## Programmable Mecanum Wheel Vectoring Robot - IG52 DB] This is a direct drive 4WD base Programmable robot kit that uses Nexus mecanum wheels. It is an Arduino robot platform for indoor robotics. It can vector in any direction. Includes a choice of an authentic Arduino for making a great Autonomous Robot.
  • [##ITEM1713## Programmable Mecanum Wheel Vectoring Robot - IG32 SB] This is a direct drive 4WD base Programmable robot kit that uses Nexus mecanum wheels and hubs. The Arduino platform is meant for indoor robotics. It can vector in any direction. Includes the choice of Arduino for making a great Autonomous Robot.
  • [##ITEM1487## Programmable Mecanum Wheel Vectoring Robot - IG32 DM] This is a direct drive 4WD base Programmable robot kit that uses Nexus mecanum wheels and hubs. Its an Arduino robot platform for indoor robotics. It can vector in any direction. Includes a choice of an authentic Arduino for making a great Autonomous Robot.
  • [##ITEM1486## Programmable Triangular Omni Wheel Vectoring Robot - IG32 DM] This is a programmable triangular Omni vectoring robot platform kit that uses Nexus Omni wheels. It's a great light duty robot kit great for indoor robotics that can vector in any direction. Choice of authentic Arduino for making a great Autonomous Robot.
For more information on vectoring robots, see our  Vectoring Robot Support page.

Motors

You need to gear an electric motor down for the same reason you have a transmission on a car or motorcycle. To get the HP the RPM is typically brought way up, especially in electric motors. If you run it 1 to 1 it will not have enough torque to move, and if it could, it would be way too fast. Take your car, for example. A normal transmission starts in 1st gear, which is the most reduced so you have the low-end torque to start moving, then as you speed up you change gears to get more speed.

With a single speed (an electric bike, golf cart, or robot) you have to find the right balance so you have enough torque to get started from zero speed, but then enough top-end speed. If you gear it down too much you will have plenty of power, but never get any speed. If it's geared too high, you will have trouble getting it started, especially up a hill, etc., but then you will have a fast top end. You need to find a balance where it works well for both. The big electric motors will help because they will muscle through it if you don't have it geared just right, but if it works too hard you will be drawing a ton of current and burning up your batteries!

A few words on motors and axles

Our line of robots are named after the size motor gearbox they use. We offer three basic styles of robots with wheels. We do this to offer different solutions to sideloading the motors.

Motor gearboxes are not specifically designed to support a load. They are designed to rotate a shaft or apply torque. To protect the motor gearbox with heavier loads, the wheel axle should be supported.

  • Direct Mount: The wheel and shaft are directly mounted to the motor.
  • Single Bearing: The motor is mounted directly to the wheel shaft, but there is an outboard bearing that helps to support the load.
  • Double Bearing: This is the most robust configuration. The wheel shaft is supported by the two bearings, and the shaft is chain or belt driven.
For more detailed information on motor mounting, visit our  ATR Support page.

Direct Mount ATR

Some platforms use a chassis with a motor bolted to it and a wheel bolted directly to the motor shaft. This works fine for light loads, our [##ITEM1930## Compact ATR robot] is a perfect example. The durability of the robot platform is directly related to the durability of the motor and gearbox. The more weight you put on the chassis the more the motor has to support.

Single Bearing ATR

For larger loads we have designed a platform that takes the vast majority of the weight off the motor and gearbox by adding a longer shaft and supporting it with an industrial ball bearing. This platform is demonstrated in our [##ITEM1473## IG32] and [##ITEM1474## IG42] ATR examples. The motor is still coupled to the wheel directly just with a longer shaft that runs through a bearing.

Double Bearing ATR

For even larger loads we designed a platform that takes all the load off the motor completely like our [##ITEM1477## Heavy Duty ATR] and [##ITEM1478## Enclosed Heavy Duty ATR]. The wheel is bolted to a high strength axle and that is supported by two industrial-grade ball bearings. Number 25 chain and sprockets connect the motor to the axle. The bearings do what they are designed to do, the motors do what they were designed to do, and the chain and sprockets link them to each other. Together this makes for a truly heavy-duty robot platform.

Picture

So say you want to get 25 mph and you have a 2 ft diameter tire, 25 mph = 25 * 5280 / 60 = 2200 ft/min. For every revolution of the tire: 2 ft * 3.14 you go ~6.25 ft. So you want the tire to rotate at 2200 / 6.25 = 352 RPM. Let's say your motor is 4000 RPM full speed, therefore you need to gear it down by 1:6.25. So if you are using a chain, you put the smallest sprocket on the motor, say 10 teeth (this will be driven by the pitch of the chain and the size of the motor shaft) therefore you will need a 62 tooth sprocket at the wheel.

Robot Speed Calculator

To Figure out how much HP, watts, or torque you need is a lot more complicated. Trial and error and experience are the best tools for this. All our motors have torque curves listed with them to aid in the decision.

Chain or belt drive motors to wheels

If you are not too sure what size motor will work for you and you are dead set on building it yourself instead of using one of our pre-configured kits, then the chain is a great way of hooking up your motors and being able to change the speed and torque without changing the motors. We offer [##CATEGORY128## chains and sprockets] for doing all sorts of gear reductions. If you want the motor to spin the same speed and have the same torque as the motor, then you go 1:1 (i.e. a 15 tooth to a 15 tooth). If you want more torque and less speed then you gear it down like 1:2 (15 teeth to 30 tooth), so the motor will turn two times for per 1 wheel revolution resulting in half the speed, but twice the power. If you want to speed things up and have extra power you can go 2:1 (i.e. 30 teeth to 15 teeth) so every turn the motor makes the wheel will make 2, but you will have half the power. The advantage of the chain drive is you can select any combination of reductions to tune your robot to work best for the weight and terrain, etc. You want to try to tune it so the motor works at its peak efficiency during normal operation. Typically you do not want to gear up too much because you lose some efficiency with reductions, etc. So if you are using a gear motor and have a 1:17 reduction in the gear motor, then use a 3:1 speed up, you are losing a lot of your power to the inefficiency of gearing down, then back up.

We have several motors to choose from. Depending on the size of your robot, how fast you want it to go, etc. If you are still having trouble deciding on the motor, select one of the pre-built kits that already have the motors selected as default.

If you are doing a very small robot see our Servo Modification Support Page so you can use hobby servos and modify them for continuous rotation.

Available Motors

  • [##CATEGORY60## Servos] - Very small robots < 5 lbs
  • [##CATEGORY76## 32mm Gear Motors] - Small to medium robots 5-35 lbs
  • [##CATEGORY77## 42mm Gear Motors] - Small to medium-large robots 5-50 lbs
  • [##CATEGORY78## 52mm Gear Motors] - Medium to large robots 25-150 lbs
  • [##CATEGORY84## 90mm Gear Motors] - Large robots up to 250 lbs
  • [##CATEGORY123## Micro Metal Gear Motors] - Very small robots < 5 lbs
  • [##CATEGORY131## Wheelchair Motors] - Large robots up to 250 lbs

Motor Controllers

Motor Controllers take signals from a microprocessor or radio control receiver and convert it into a high current varying voltage. We carry many variations and sizes of motor controllers. We carry RoboteQ motor controllers, some of which will take encoder inputs for speed and / or position control, as well as Dimension Engineering's Sabertooth with a Kangaroo for encoder input.

Pictures 

For more help with using encoders with motor controllers, please visit our  Motor Controller Support Page, and our  Encoder Support Page.

For Help selecting the right motor controller, review each item and their associated data sheets / manuals.

For a complete list of all of our motor controllers, follow this link.

  • [##ITEM2233## Roboteq’s XDC2460] controller is designed to convert commands received from an RC radio, Analog Joystick, wireless modem, PC (via RS232 or USB) or microcomputer into high voltage and high current output.
  • [##ITEM1834## RoboteQ MDC2460 - 2x60A 60V Motor Controller with Encoder Input] Roboteq’s MDC2460 (2x60A 60V) controller is designed to convert commands received from an RC radio, Analog Joystick, wireless modem, PC (RS232 or USB) or microcomputer into high voltage and high current output for driving one or two DC motors.
  • [##ITEM1826## RoboteQ SDC2160 - 2x20A 60V Motor Controller with Encoder Input] Roboteq’s SDC2160 (60V) controller is designed to convert commands received from an RC radio, Analog Joystick, wireless modem, PC (RS232 or USB) or microcomputer into high voltage and high current output for driving one or two DC motors.
  • [##ITEM1822## Sabertooth Dual 32A Motor Driver] The Sabertooth 2X32 is one of the most versatile, efficient and easy to use dual motor drivers on the market. It is suitable for medium powered robots - up to 30lbs in combat or 100lbs for general purpose robotics. Made by Dimension Engineering.
  • [##ITEM1546## A4988 Stepper Motor Driver Carrier with Voltage Regulators] The A4988 stepper motor driver carrier with voltage regulators is a breakout board for Allegro’s A4988 microstepping bipolar stepper motor driver.
  • [##ITEM1545## A4988 Stepper Motor Driver Carrier] The A4988 stepper motor driver carrier is a breakout board for Allegro's A4988 microstepping bipolar stepper motor driver.
  • [##ITEM1544## DRV8825 Stepper Motor Driver Carrier, High Current] The DRV8825 stepper motor driver carrier is a breakout board for TI's DRV8825 microstepping bipolar stepper motor driver.
  • [##ITEM1424## Pololu Zumo Shield for Arduino] This shield mounts onto an assembled Zumo chassis and makes it easy to build an Arduino-controlled Zumo robot.
  • [##ITEM1368## Pololu DRV8833 Dual Motor Driver Carrier] This tiny breakout board for TI’s DRV8833 dual motor driver can deliver 1.2 A per channel continuously (2 A peak) to a pair of DC motors.
  • [##ITEM1297## Dual MC33926 Motor Driver Shield for Arduino] This shield makes it easy to control two brushed DC motors with your Arduino or Arduino-compatible board. Its dual MC33926 motor drivers operate from 5 to 28 V and can deliver a continuous 3A per motor.
  • [##ITEM1296## Dual VNH5019 Motor Driver Shield for Arduino] This shield makes it easy to control two high-power DC motors with your Arduino or Arduino-compatible board.
  • [##ITEM1225## Sabertooth Dual 60A motor driver] Dimension Engineering Sabertooth 2X60 is one of the most versatile, efficient and easy to use dual motor drivers on the market. It is suitable for high powered robots - up to 120lbs in combat or up to 1000lbs for general purpose robotics.
  • [##ITEM1197## SyRen 50A Regenerative Motor Driver] Out of the box, the SyRen 50 can supply a single DC brushed motor with up to 50A continuously. Peak currents of 100A are achievable for a few seconds. Made by Dimension Engineering.
  • [##ITEM1155## Sabertooth Dual 12A Motor Driver] Dimension Engineering Sabertooth 2X12 is one of the most versatile, efficient and easy to use dual motor drivers on the market. It is suitable for medium powered robots - up to 30lbs in combat or 100lbs for general purpose robotics. Replaced TE-091-210.
  • [##ITEM1143## Sabertooth Dual 12A RC Motor Driver] Sabertooth 2X12 R/C is a dual motor driver specifically optimized for use in radio controlled vehicles. The Sabertooth 2x12 RC replaces our custom 2x10 RC controller. Made by Dimension Engineering. Replaces 2x10 RC (TE-115-210).
  • [##ITEM851## Sabertooth Dual 5A Motor Driver] The Sabertooth 2X5 is one of the most versatile, efficient and easy to use dual motor drivers on the market. It is ideal for smaller robots- up to 3lbs in combat or 25 lbs for general purpose use. Made by Dimension Engineering.
  • [##ITEM345## MD22 Devantech Dual Motor Driver] The MD22 by Devantech is a robust low/medium power motor driver. The driver is designed to supply power for two independent motors.
  • [##ITEM2630## RoboClaw 2x60A Motor Controller] The RoboClaw 2x60A is an intelligent motor controller designed to control two brushed DC motors at 60 Amps continuous with up to 120 Amps peak per channel.
  • [##ITEM2629## RoboClaw 2x30A Motor Controller] The RoboClaw 2x30A is an intelligent motor controller designed to control two brushed DC motors at 30 Amps continuous with up to 60 Amps peak per channel.
  • [##ITEM2627## RoboClaw 2x15A Motor Controller] The RoboClaw 2x15A is an intelligent motor controller designed to control two brushed DC motors at 15 Amps continuous with up to 30 Amps peak per channel.
  • [##ITEM2626## RoboClaw 2x7A Motor Controller] The RoboClaw 2x7A is an intelligent motor controller designed to control two brushed DC motors at 7.5 Amps continuous with up to 15 Amps peak per channel.
  • [##ITEM2628## RoboClaw Solo 30A Motor Controller] The RoboClaw Solo 30A is an intelligent motor controller designed to control one brushed DC motors at 30 Amps continuous with up to 60 Amps peak.

A very common question that we get is "how do I hook up four motors to a two-channel motor controller?" Most of our 4WD robots use four motors (one motor per wheel).

Since the left motors need to act together as do the right motors, the solution is very easy. Just parallel the left motors to one channel of the motor controller, and parallel the right motors to the second channel.

The same goes for 6WD robots. Just make sure the sum of the stall torque for each motor does not exceed the motor controller rating. (ie: 2 motors with 15A stall will exceed the rating of a 25A controller in a stall condition.

Robot Batteries

When selecting the appropriate batteries for your robot, you need to size them by voltage to match the desired motors and motor controller. You will also need to take into consideration the maximum current output and the battery type and capacity.

Voltage Rating

Our motors are rated for either 12V or 24V. Incorrectly providing a 24V source to a 12V motor will immediately cause permanent damage. If only connected for a short period of time the observed damage will be limited to a whining sound when the motor is moving. A prolonged over-voltage condition will cause catastrophic damage to the motor and this may pose a significant risk of fire, injury, or death. Be sure that the appropriate power is applied to the motors. If the motors receive insufficient voltage, say 12V to a 24V motor, the motor will either move very slow or not at all.

In order to distribute the weight of a battery evenly across the robot, its common practice to use multiple 12V batteries to prevent the robot from favoring one side while driving. For a 12V motor system, the batteries will need to be connected in parallel and for a 24V system, they will need to be connected in series.

Note: When using a multiple battery system, always be sure that each battery is individually fused.

Maximum Current Output

When selecting the appropriate battery source, it is wise to be sure that the battery can produce the amount of current needed by your motors and motor controller. Take, for example, Dimension Engineerings Sabertooth 2x12 motor controller. It has two channels and each channel is capable of outputting 12A so for the motor controller to be able to supply a total of 24A to a pair of motors the battery providing power to the system must be capable of supplying that amount of current. It is important to note that the motor system may not be the only major component in your system. Be sure to account for the additional loads on your system, such as a computer, control system, sensors, and a radio.

Note: For many hobby RC motors, the batteries will be marked with a C rating. This rating will indicate the maximum continuous current discharge that the batteries are capable of. The C rating is a multiplier that can be applied to the battery capacity to get your maximum continuous discharge. For example, a 2,000mAh 10C battery can output a maximum of 20,000 mA or 20A.

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Battery Type and Capacity

There are two main types of batteries that are discussed here: Lead Acid, Lithium. Lead-acid batteries are the cheapest out of the two. These are the batteries that you typically see in a car or a truck. They do not require special circuit protection, only a fuse. The downside is that they are large and very heavy.

The second type are Lithium batteries. You will typically see in most electronics today. They are lighter and more compact than lead-acid batteries and are the go-to battery type for RC robotics. One caveat that with Li-ion batteries is that they require specific under-voltage circuit protection to prevent the battery from dropping too low. If this happens the battery will be unrecoverable. Most of our Lithium batteries contain the necessary circuit protection to prevent this from happening. Most of the cheap RC batteries you see listed online, do not.

There are several kinds of Lithium batteries. Lithium-ion is the most common (and the most unstable). Lithium-ion require extreme care so they do not overheat, etc resulting in a fire or explosion. A more stable battery is LiFePO4 chemistry as in our [##ITEM1140## K2 25.6V] or [##ITEM1139## K2 12.8V] batteries. These batteries are much more stable and an excellent choice for powering robots, but they are more expensive.

On the topic of battery capacity, it is commonly measured in mAHr (milliamp hours). This is a measurement of how long it would take to discharge the battery if it outputted 1mA of current. Larger batteries are typically measured in AHr which is mAHr divided by 1,000. So, a 12V 2000 mAHr (2AHr) battery will last twice as long, under the same conditions, like a 12V 1,000 mAHr (1AHr) battery.

Robot Battery Chargers

When ordering a robot kit as a base for your project, we offer appropriately sized chargers for the supplied batteries. When picking out your own chargers, it is absolutely critical that you pick the charger with the correct voltage and battery type. Not selecting the appropriate charger will be a fire hazard and cause permanent damage to the battery, charger and your property.

Robot Controller

There are several options for controlling your robot. The big division of remote control is between Analog versus Digital Control.

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Analog

Analog Control provides the simplest link between the operator and the robot possible, it is, however, one way. Video is typically transmitted back over an open analog channel. Analog video transmissions can be viewed on any receiver, both yours or anyone else. Analog Remotes similar to R/C Aircraft can be used to control the robot, or a custom controller can be made to control and display the video in a case. We offer several types of analog controllers.

(RC) Control: (Handheld wireless control devices)

  • [##ITEM2155## Spektrum DSMX DX6i Transmitter Only] This is a 6-channel 2.4GHz DSMX aircraft system transmitter.
  • [##ITEM2150## Spektrum USB-Interface] This is a 5-channel 2.4GHz DSM2 aircraft system transmitter. It replaces the DX5e transmitter (as of 12/18/15).
  • [##ITEM1331## Spektrum DSM2 AIRMOD w/AR7010 FUT-Compatible] Each module system includes everything you need to equip your Futaba module-based system with the interference-free, glitch-free precision of DSM2.
  • [##ITEM1030## Spektrum AR6110e DSM2 ML 6Ch Fail Safe Receiver] Spektrum’s 2.4GHz DSM2 technology gets even smaller with the AR6110e 6-channel DSM2 Microlite Park Flyer Receiver with End Pins. Ideal for compact airframes or small robots!
  • [##ITEM995## Spektrum Remote Receiver Extension] - 36 inch This is a 36-inch remote receiver extension for Spektrum.
  • [##ITEM994## Spektrum Remote Receiver] The remote receiver can be used as a replacement for the AR6200, AR7000 and the AR9000 remote receivers. It can also be used as an optional fourth remote receiver for the AR9000.

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For more help with Remote Control (RC), please visit our  Remote Control Support Page.

Digital Control

Digital Control of a robot uses Ethernet over a wireless link to control the robot. The wireless link will be over standard WiFi, CoFDM, or a Dual Band Wireless Link similar to WiFi. Our Digital Remotes are enclosed in a Pelican (or Pelican-like) case that houses the radio, control joysticks and switches, and the video monitor.

Digital Wireless Control Systems

  • [##CATEGORY138## Routers and Bridges]: Routers and Bridges to provide Wireless capabilities to your robot!
  • [##CATEGORY139## Wi-Fi Control Packages]: Pre-configured WiFi control systems to get your robot up and running! These control systems come assembled and tested by our staff to ensure out-of-the-box functionality.
  • [##CATEGORY159## XBee, Zigbee, and RF Wireless Communication]: These modules allow a very reliable and simple communication between anything with a serial port! Point to point and multi-point networks are supported.
  • [##CATEGORY100## Tactical Robot Controllers]: There are many ways to control a robot. We offer a wide range of military grade tactical controllers. Find the controller that works best for you.
  • [##CATEGORY160## Antennas and Pigtails]: 2.4 Ghz antennas and pigtails for wireless routers and radios
For more help with Remote Control (RC), please visit the following support pages:
* Remote Control Support Page
* Network and WiFi Support Page
* Wireless Serial Support Page
* Tactical Robot Support Page

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Complete Control Packages

We offer [##CATEGORY206## Complete Control Packages] to control the robots. These are complete systems that are custom configured to your needs that will connect your robot.

  • [##ITEM2355## Programmable RC Control Interface Package]: This package offers the simplicity of manual RC control while having access to the diversity of Arduino I/O.
  • [##ITEM2353## Programmable GPS Navigation Package]: This package includes all the items you would need to make a robot drive to GPS waypoints autonomously.
  • [##ITEM1846## WiFi Remote System with Tablet OCU]: This package is for controlling SuperDroid Robots. It contains a WiFi Router, Serial Bridge, Power Supplies, Custom Controller Board, Video Server, Tablet with custom robot control and interface with video monitoring.
  • [##ITEM1727## Programmable xBee Control Interface Package]: This package allows you to control a robot, out of the box, using the power of Arduino and xBee. The remote comes standard with an ABS enclosure and your option of 2, 3, or 4-axis joystick.Full source code is provided!
  • [##ITEM1440## Programmable WiFi Custom Control Interface Package]: Fully configured, tested, and supported. This package comes with a network device, Arduino Mega control board, Arduino Ethernet Shield V2, SDR Arduino Mega Sensor Shield, and a 4x TTL relay board. It will fit on top of any of our chassis options.
  • [##ITEM2369## ROS Autonomous Control Package]: This package provides a completely assembled and configured Robot Operating System (ROS). ROS is a Linux based meta operating system for your robot with a massive open source community.

Autonomous Control

This is a huge topic due to all of the self-driving cars, etc. This, however, is not a simple or trivial task. Google has spent billions of dollars in development.

If you are interested in building an autonomous robot, then please follow these links to help get you started.

  • Programmable Arduino Robots: (LINK: cat 157) Programmable Robots. These mobile UGV robots have an Arduino for their controller. These Arduino robots are easy to program and a powerful processor allowing the user to create autonomous robots.
  • Programmable Robots: (LINK: cat 194) Programable Robots. Autonomous Robots. Robots that think on their own and do set tasks. They range from customized Arduino WiFi robots to programmable tactical robots.
  • Control Systems: (LINK: cat 206) These custom control systems will allow you to control your robot wirelessly,autonomously, or both. Autonomous GPS navigation. Control and monitoring your robot wirelessly over WiFi. If you need something custom, contact us.
  • Programmable SDR Robots: (LINK: cat 75) These programmable robots are designed by SuperDroid Robots. They range from customized Arduino WiFi robots to programmable tactical robots.
  • Sensors: (LINK: cat 35) We have sensors to help you detect gasses, conduct surveillance, and measure performance. These sensors can help toward building an autonomous robot.
  • Build an Autonomous Robot: Bought one of our robots? Want to make it autonomous? Start here! We walk you through design decisions and the required components for you to develop your own autonomous robot.
  • Autonomous Robot Services: Autonomous robots are a challenge as they require a precise blend of mechanical, electrical, and software engineering. We have the capabilities to design and develop the autonomous solutions you require.
  • Autonomous WiFi Robot Arduino Robot Programming: The page describes the method and gives examples of how we programmed the Free Autonomous WiFi Robot Arduino Robot in our give away.
  • Sensor Support: We carry a large array of sensors to enable you to develop a smart and autonomous robotic solution.

Wiring

Power and Battery Wiring

When wiring your batteries to your robot there are concerns you must address. Namely, what output voltage do you need and how you are going to charge the batteries. When using two 12V batteries you will need to wire them in parallel to power 12V motors and in series to power 24V motors.

The key things to consider are what voltages do you need and how much power The driving force for the main battery will be the motors. We typically use 24VDC motors, they run at half the current for the same power as 12V motors so smaller wires, motor controllers, etc. Do you need a separate battery for the controller or on-board computer, etc? How are you going to get those voltages (multiple batteries, voltage regulators, etc.)? How much of a load will be on each voltage so your batteries and/or regulators are sized properly? This will help you size your batteries: simple math. If you have a 1Amp load and a 10Ahr (10,000mAhr) battery, the battery will run for 10 hours in theory. 

For more help with wiring, please visit our Robot Wiring Support Page.

Motor Wiring

Generally motors are wired to a motor controller to provide speed control to motors. The motor controller can be used to change the directions of the motor as well. If running motors in parallel (as in a 4WD the two left and the two right motors will be running together in parallel) you can wire them in parallel too.

We have a lot of information on how to wire motors, etc. on our Motor Wiring Support Page. 

 For more help with wiring, please visit our Motor Wiring Support Page.

Sensors

We offer a wide range of sensors. The more sensors used, the better the autonomy will be. Relying on only one type of sensor for all your positioning will work for simple situations, but will probably cause issues for any complex positioning or for any positioning that requires higher precision.

In robotics, sensors can be used to monitor your environment or to determine your robot's position relative to some object. Standard sensors for environment monitoring can range from temperature thermocouples, gas, and radiation. The standard positioning sensors are Sonic and IR for object detection and GPS, gyroscopes, and accelerometers to determine relative location, direction, and airspeed. For ground travel and RPM feedback, a combination of our encoder enabled motors and our encoder buffer board make it incredibly easy to implement your own speed control algorithms and RPM feedback. The encoder can also be used to keep track of the distance traveled, but with skid steer the more you turn/skid the more inaccurate the reading because of the wheel slips/skids resulting in encoder counts, but no relative movement.

  • For a complete list of our available sensors, please visit this link (LINK: cat 57).
  • Accelerometers, Gyros, GPS, & Compasses: Accelerometers, Gyros, GPS, & Compasses. Measure acceleration and track rotation with these accelerometers, gyroscopes, compasses/magnetometers, and combined inertial measurement units (IMUs) and orientation sensors.
  • Contact Sensors: Contact Sensors. Switches and Bumper Switches used to indicated when a physical limit has been reached.
  • Current Sensors: An assortment of unidirectional and bidirectional Hall effect-based current sensors. They offer a very low-resistance current path and electrical isolation between the current source and the measuring circuit.
  • Force Sensors: Force-sensing resistors (FSRs) are passive components that exhibits a decrease in resistance when there is an increase in the force applied to the sensor allowing you to create a sensor that is able to detect force or pressure.
  • Gas Sensors: Gas sensors makes it possible to measure concentrations of gasses such as alcohol, methane, propane, butane, and carbon monoxide.
  • Magnetic Guide Sensors: Precision magnetic sensor for detecting and measuring the position of a magnetic track along the horizontal axis, for use in Automatic Guided Vehicles and other Automation applications.
  • Optical Sensors - IR, PIR, Photo, & Lasers: Optical IR Sensors & Laser Range Finders. IR distance sensors make it easy to detect and range objects. The laser range-finder is inexpensive, accurate and easy to use with a 240 degrees scan area.
  • Sonar Range Finders: Accurately measure distances over a wide range with our assortment of ultrasonic distance sensors from Maxbotix and Devantech.
  • Temperature and Humidity Sensors: These sensors measure the humidity of the air and can measure the temperature. Great features for your microcontroller project.
 For more detailed information on sensors, visit our  Sensor Support page.
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