Continuous Use Quadruped and Wheeled Robot

Help & Support Robots & Kits
1

Hello,

I have a few questions regarding a new system I am working on.

Firstly, I am interested in redesigning the quadruped kit (Lynxmotion Symmetric Quadruped Kit) such that it has the capacity to run continuously for an hour or so. I currently have two separate quadrupeds for which I can test with. My specific questions regarding this design are:

  • Is there a way such that the quadruped can be plugged in so the battery does not need to be replaced, such as through a power supply (similar to a Tektronix power supply)
  • Are there more powerful Servos that I could use in place of the Servos that have already included in the kit, such as ones that do not overheat after an hour of use? How many of such Servos would I need and how much would they cost?

Another question I have for a continuously running robot is the possibility of using a smaller wheeled robot that does not overheat and can run for many hours. This wheeled robot also needs to have the capability of having a single Sensor (Parallax PING Ultrasonic Sensor) attached to it, as well as a Bluetooth Bee (such as the Bluetooth BLE Link Bee)? Does such a robot exist? If not is there another robot in the market that could run continuously that you would recommend (such as a smaller quadruped robot) that still has the ability to have sensors attached?

Thank you so much in advance for your help!

Best,
Christopher

2

Just following up on my previous post. Please let me know if you have any ideas regarding some of the issues I am attempting to address.

Thanks again!
Christopher

4

Hi,

  1. The SSC-32U Board which controls the Lynxmotion Symmetric Quadruped Kit doesn’t have an onboard battery manager/charger circuit. Therefore, only one power supply can power the servos of the quadruped through the VS1/VS2 screw terminals, either a battery pack or a wall adapter or a lab type power.
  2. The Lynxmotion Symmetric Quadruped Kit includes 4x HS-422 Servos (57 oz.in at 6V) and 8x HS-645MG Servos (133 oz.in at 6V). The digital version of the HS-645MG is the HS-5645MG which is slightly more powerful than the HS-645MG (168 oz.in at 6V).
  3. How long the robot will run is strongly dependent on the battery pack capacity that provides the power to the servo and how much power this robot consumes. The more powerful the robot is (higher torque servos or motors for a wheeled robot), the less time the battery will last. Having additional sensors and communication modules as a Bluetooth Bee will also draw current and drain the battery faster even if sensors power consumption is negligible compared to the robot’s actuators power consumption. We invite you to take a look at our Wheeled & Tracked Robots section. The Makeblock mBot v1.1 Blue STEM Educational Programmable Robot (Bluetooth) is a popular wheeled robot. It comes with an Ultrasonic Sensor and a Bluetooth module.
5

Thank you very much for your response!

  1. It seems like I will be able to use my Textronix power supply, which is great! However, are there any other power supplies or adapters that you would recommend, if any?
  2. How many of the HS-5645MG will I need to purchase to replace my current Servos for continuous use for around an hour?
  3. The Makeblock mBot seems like a good potentiality if I am unable to get my quadruped to run continuously for around an hour.

Thanks again for your help!

6
  1. The HS-422, HS-645MG and HS-5645MG operate at 4.8V-6V. From the servos specs, a HS-422 servo consumes 800mA and a HS-5645MG consumes 2400mA (at stall). The HS-5645MG would replace the HS-645MG servos, therefore, your total continuous current consumption for the servos of the quadruped can be approximated as 25% of stall current : ((800mA x 4)+(2400mA x 8)) x 0.25 = 5600mA. Therefore, please ensure that your Textronix power supply is outputting 6V and that can provide at least 5.6Amps continuously. We offer this Switching Power Supply 5V 10A which will work in your setup. The servos will be slightly slower (because they will be powered at 5V instead of 6V) but the current rating is more than sufficient.

Firstly, I am interested in redesigning the quadruped kit (Lynxmotion Symmetric Quadruped Kit) such that it has the capacity to run continuously for an hour or so.

Since you are planning to operate the robot for at least an hour continuously without charging the battery, you can take a look at a high Ah 6V battery as this 6V, 10000mAh Rechargeable NiMh Battery. Based on the calculation above and if this battery is fully charged, it will be able to supply enough power for the robot for at least an hour.

  1. As mentioned above, the HS-5645MG servos would replace the HS-645MG, therefore, you would need 8x HS-5645MG for each quadruped. We unfortunately don’t offer more powerful servo with the same dimensions as the HS-422. So the quadruped would have 4x HS-422 and 8x HS-5645MG.
2 Likes
7

Thank you very much for your response! It is very helpful!

  1. I will likely just end up using the rechargeable battery, but if I need to use the quadruped for a longer period of time, that power supply from Robot Shop sounds awesome!
  2. Great, thanks. I will likely just order 8 of those!

Best,
Christopher

1 Like
8

You have to take care since Hitec servo motors are normally not meant to run for hours without pause.

I may be wrong but regular servos shouldn’t be working for more than 10-15 minutes before they take a short brake. They are really lazy.