View Full Version : R/C zip line camera dolly

09-26-2006, 09:01 PM
I am looking for some information about r/c motors and controllers for a project I am working on and since I have no r/c experience(except for an r/c car that I got as a grad gift back in 1986 called `the frog`) Iím looking for anyone here to answer some questions that I have. I did post this question at R/C universe and they were very helpful, they did however suggest that I also question you guys here at Watt Flyer, mentioning something about ď2 turn brushless motorsĒ. The project is a zip line camera dolly. Basically a steel cable zip line suspended about 30 feet above the ground with an r/c controlled dolly that carries a digi cam back and forth. With that we are filming sections of a downhill bike trail with most sections of the trail not readily accessible by vehicle and since the equipment will need to be carried in by hand, portability, self contained power supply and, most importantly, lightweight equipment is key. If the filming results with this type of device are acceptable than we might put it into regular use, but before we can even get to that point we need to thoroughly test, fine tune, and master control of the device therefore good quality components with reliable and repeatable results are required. The trolley is still in the design phase and exists only in drawing form so it can be adapted to accommodate the r/c components, but itís the r/c components themselves that I need help with. So to sum it all up, this is my question. What type of motor, transmission, and drive wheel would be needed to move aprox 15 lbs of gear on steel wheels at speeds up to 40 mph? The camera/dolly device along with the auto pan/tilt device will weigh in at 15+lbs, however we can scale it back to just the camera/dolly device and weigh in at aprox 5-8lb. The 40 mph figure is the max, most riders run at 5-10 mph and only occasionally reach flat out speeds of 30-40 mph. The max distance that the dolly would be required to run is aprox 250í. The drive wheels will be two hard rubber wheels in compression against the cable. The dolly will be of an open air design along with some sort of cooling fan/duel motor set-up and be used outdoors therefore overheating might not be an issue. I hope this gives you a clear idea of what I am trying to build. Also info about batteries, controllers, and anything else you might think necessary to complete this project would be helpful. Thanks.

09-27-2006, 05:25 AM
I thought about this a bit and I'm not sure plane parts will do it for you. I would think about a pair of E-Maxx RC truck transmissions with the Novak brushless system in each. It takes some torque to get 15 pounds moving and getting it to 40mph takes lots of raw power. A E-Maxx gearbox on each end of your dolly hooked right to the drive wheels should get you in the ball park. Gearing is easy to change for different speeds and drive wheels sizes and most hobby shops carry the spare parts. I'm sure there are lots of ways to do this but everything I come up with is well over $1,000 to pull off. Lets see if we get anymore ideas here.





09-27-2006, 01:56 PM
thanks for all the advice and information with my project. your input has given me a lot to consider and when it is complete i will post some pics of the finished project. thanks