Hello Robot Dude
Can you tell me why a serious post of mine was completely deleted? Do you automatically delete post without ever reading them. I can assure you that if anyone at this site read my post they could have confirmed that there was no spam, just serious questions about tracks for my robot.
If you need any further proof that I have such a robot I will be glad to post some pictures of it.
Awaiting you intelligent reply.
Bill Rogers
Hello Bill,
We have deleted no posts of yours, and we certainly do not delete posts without reading them. Are you sure you hit “submit” and not “preview”?
Beth or Snailkeeper
Yes did hit the post and not the review button and received a message saying that at least one good post was necessary before any would be accepted and a waiting period of 24 hours would also be necessary.
To recap my original post. I have built a Johnny 5 type robot. Right now it stands about 42 inches tall but will grow to over 5 feet tall when I am through reuilding it. It now uses wheels and I have been looking for tracks now for a couple of years until I found your site. My question is will your tacks support a bot that weighs 40 to 80 pounds? I am not sure if my little bot weighs that much but I am still adding to it. I also like the turn table on your J5 and wonder if it too would support the weight. I started with Evolution Robotics kit and added to it. In the begining I would not have purchased that kit but I also found a chattebot program that speak and understands spoken English as does the robot. Now I can not only have a robot that can be programmed to perform some simple tasks but can carry on a normal conversation with me as it learns all my likes and dislikes.
Bill
With the kind of weight you’re talking about, there’s not many materials that can handle this kind of load. Billet aluminum or carbon steel perhaps, but not lexan or thin aluminum brackets. Also, with a bot 5 feet tall with the same Johnny 5 base, is going to be way to top heavy! Fore something that is going to be 5 feet tall, you will need a much larger base. Servos will be another issue, anything more than 6 to 8 pounds, you will not be able to move it. Perhaps Jim can give you the true weight limits the available servos can handle.
Is your bot custom built or are you using one of LM’s rover platforms? What is the current dimmensions of your rovers base?
The tracks can surely support the weight. The 3.0" wide version are used on police robots that weight over 100 punds. I can’t guarantee the sprockets can handle the torque involved, but the tracks certainly can and do support the weight. Good luck with your bot, and sorry the forum spam filter prevented your message from showing up. Depending on which browser used you may be able to click back and remove links or images, and not lose your post. We had to add the filter because we were bombarded with junk.
It sounds like you tryed to post a URL or Picture. In that case you need a good text post.
To clarify my last post, I was talking regarding the chassis. I had no idea the tracks can support 100 lbs! I was thinking more like 20 lbs.
has any body tried to chain drive multible sets of sprockets too spread the load out for high torque motors??
mmm, 4 tracks, 4 motors two on each side with chains… this would be awesome!!!
The tracks are definitely stronger than they look. Actually they are incredibly strong. I would trust them on any 100 pound rover. You have to see them to believe it. They are excellent quality.
Might be good to precisely define just what the term “support” entails. Tracks can be subjected to dynamic loads that could be quite high depending on the situation.
I think if the plastic sprockets were aluminum it would be able to hold an emense amount of weight, but it only goes as far as how the injection molded tracks can handle before being crushed under wieght.
I’m sure you could get custom CNC machined sprockets if you had an application that needed them. There are lots of companies that offer this service.
Aluminum sprockets are unnecessary and would probably create early wear in the plastic track. Acetal, Polyurethane, and glass-filled Nylon are plenty strong enough materials for sprockets and much cheaper to have formed, than to have aluminum machined. Especially since the tracks use a unique tooth layout meaning it would have to be extruded or molded aluminum.
The way the tracks are designed, the load it distributed among many sections that share the weight. Kind of like the bed of nails theory. Meaning I would have no doubt that you could easily pull a full sized car onto 4 pieces of track and have roughly 1000 pounds on each piece without any damage or buckling at all.
As far as linear loads go, I’m not sure. I would guess that they could easily take any torque end effects from a 100 pound rover with equivalent torque. Side load resistance is great. And would fall into the same range as linear pull load limits. The strength of the tracks far exceeds any loads or forces seen on a rover that would use a track this size.