Ok, I built this robot called the SPY1. Its basically a robot for a science fair I was in a while back. I wanted this robot to be very practical. Unfortunately the judges werent too impressed with the way it runs on carpet, cement and other tough terraine. I have 6mm shaft motors and hubs with 4 Off Road Robot Tires - 5.0"D x 2.25"W (pair). The robot works great on smooth surfaces such as hardwood and tile, but dosent turn good on rough cement, carpet or grass becuase the skid steering causes way too much friction. I am using I hitec laser 4 to controll it by the way.
Anyway, the motors are securely screwed into the robot so that shouldn’t be the problem. I think it has to do with the tires cause their soo puffy and soft.
All of the lynxmotion robots seem to be able to drive on all kinds of terrian with no problem in the videos. I need some help, this isnt working.
I’m not a rover guy, but I can take a few guesses…
Are your tires so “poofy” that they sink slightly under the rover’s weight?
If they don’t actually do so, then I doubt that your traction is actually a problem.
If, indeed, they do squish quite a bit, then the tire will be flat on that side.
As I’m sure you’re well aware, flat objects don’t roll very well.
It sounds more like your motor’s torque being a problem.
Mind telling us which ones you’re using?
If the torque that your motors can produce from a standstill is pretty weak, you’ll experience problems like you have on surfaces that don’t conserve energy (have high friction).
I’ve experienced this with a few toy RC cars.
Those tiny 3-5V motors don’t do diddly squat on high-friction surfaces because they just can’t get the startup torque to get rolling.
well, like nick said above, flatd oesn’t roll very well so id say that your tires are too soft, maybe you can get some foam inserts in the tires if you dont have them already, it may help if make them a little bit less poofy
Did you glue the tire to the rim? I used 6 Off Road Robot Tires - 5.0"D x 2.25"W tires putfile.com/pic.php?pic=6/17517493578.jpg&s=f5
on a 30 pound platform and found that the tire itself will spin on the rim under high torque. I glued them and now get full torque transfer from motor to rim to tire to surface. If you havent glued them, try a couple of drops and see if it works better. If it does - glue the whole darn thing like I did. (Caution - this comes with the obvious problem of dissassembly should you need to)
You also might consider some of that expanding foam, take some of the foam and peel away the rim of the tire and sqeeze some of it in there, keep guestimating that until the the tire is filled up, the expanding foam will harden and then you will have basically a solid tire. I have used this on really dry dusty tracks when racing rc cars.
thx, I hope the gluing works. but can I also get more speed by over-volting the motors?? I am using 7.2 volts at the moment. How high can I push the power?
the same motors used in the 4WD rovers. There 6mm shafts with 200rpm. Im not sure If I should get stronger motors or get a new battery, but I dont know which is the strongest type at lynxmotions.
I wouldn’t go any hire than 1-2vlts over what they are supposed to be run at. this will shorten the life of the motor but it will increase performance. anything over that will either make magic smoke and sparks or it will decrease the performance of the motor.
Well, the “strongest” type are the planetary motors.
Those have different dimensions than your motors, though, so I’d check them before you get your heart set on them.
I believe they’re quite a bit longer than your average gearhead motor.
Within the gearhead motors, the strongest ones will be the ones with the highest gear reductions.
That being said, they’ll also be the slowest.
If you don’t mind a bit of top-speed loss, more torque will give you better acceleration.
If this is an inside-bot, the chances are that it’ll never reach it’s topspeed, anyhow, especially on carpeting.
s