Need help building 3 wheel rc car
#16
Tech Elite
iTrader: (6)
If you are allowed to use two motors then just hook up a motor to each wheel & use steering like a tank. Not to mention you will have double the power. Then you can pick up a cheap 4 ch plane radio & use the 2 joysticks for your two throtle servos w/ reverse. I mean, two $50 escs, two $30 motors, a $50 radio, $40 in tires? That should easily land in your budget. You can build a chasis shaped like a T. Then go and mount the wheels w/ motors on each side & then mount the other wheel which is nothing but balance, you want it to slide around. If you are only allowed to use one motor then hook up the motor to a diff & use a braking system that will allow you to lock one wheel & deliver power to the other wheel.
http://www3.towerhobbies.com/cgi-bin...&I=LXELT4&P=ML
Unfortunately, for the sounds of it, you only get to use 1 motor
#17
Thanks for the many suggestions and sorry that i haven't been able to reply sooner. I am actually in 3 design classes this quarter The restriction given is pretty strict and can't be changed nor bent. Everything used has to be well documented and bought new w/ receipt. Oh,we can only have 1 motor and a servo for steering.
The group has decided have a larger 1 rwd and 2 front for steering. The chassis is modeled around the battery and most of the component lies ontop of the battery so the vehicle is slim and compact. We are still unsure of whether to have a rear suspension but so far the CAD model has the shocks set 45 deg and between the rear wheel axel and a brace from the chasis. From the CAD drawing, the center of mass is also at equal distance between the tires and approx the height of the rear tire.
These are the rear tires we're currently considering:
http://www.tm-rc-racingcomponents.co...FrameSet11.htm
We are still a little worried about traction since we will be driving on tiles. Then again, I read that our motor isn't very powerful. How does everything sound so far? We are also required to test in a wind tunnel.. Would it be ideal to mold to body over the entire front that are sticking out or just the main body?
The group has decided have a larger 1 rwd and 2 front for steering. The chassis is modeled around the battery and most of the component lies ontop of the battery so the vehicle is slim and compact. We are still unsure of whether to have a rear suspension but so far the CAD model has the shocks set 45 deg and between the rear wheel axel and a brace from the chasis. From the CAD drawing, the center of mass is also at equal distance between the tires and approx the height of the rear tire.
These are the rear tires we're currently considering:
http://www.tm-rc-racingcomponents.co...FrameSet11.htm
We are still a little worried about traction since we will be driving on tiles. Then again, I read that our motor isn't very powerful. How does everything sound so far? We are also required to test in a wind tunnel.. Would it be ideal to mold to body over the entire front that are sticking out or just the main body?
#18
Tech Master
iTrader: (8)
I'd suggest avoiding foam tires on a tile surface. You will get virtually no traction. I think an offroad tire with small pin spikes or a softer rubber tire with with some sort of tread will work best. Perhaps something like this https://www.ssl-stormerhobbies.com/c...ns&pn=ORN76403 or this... https://www.ssl-stormerhobbies.com/c...ns&pn=ORN76415 If you do decide to go with foam I'd suggest something for a 1/8th scale car so you have a larger contact patch. Also, I think you'll get the best aero from having the body over the front. suspension and tires/wheels.
#19
Im soon to be an engineering student so here's my input....try making the layout 2-wheels steering and one huge thick wheel at the back like the concept cars developed and recent motor shows...
The reason is having one front wheel for steering I fear would have not enough steering for you to manuevour around slalom courses.....for backwheel traction try using those nitro 1/8 rear foam wheels.......try using softer shores.....should be sufficient for traction.......
The reason is having one front wheel for steering I fear would have not enough steering for you to manuevour around slalom courses.....for backwheel traction try using those nitro 1/8 rear foam wheels.......try using softer shores.....should be sufficient for traction.......
#20
hmm, a lot of mix inputs on the tires.. The tiles is outdoors so it isn't polished and shiny but they are much smoother than concrete.