[TANKS] Re: new progress
I am guessing from teh top of my mind that this is number 66. Few wheels, sweet and swift. Great ground clearance too. Is that a friction driven tank? Chrys - Original Message - From: To: "R/C Tank Combat" Sent: Sunday, April 05, 2009 1:10 AM Subject: [TANKS] Re: new progress > > I now have the little fella moving and have posted a Vid on you > tube , > I have completed the spring suspension system since making this film > as wheel 3 was fixed. and its very nice driving a tank having full > suspension . > > http://www.youtube.com/watch?v=-DM7dT3Yxow > > Neil R > > > > > __ NOD32 3434 (20080911) Information __ > > This message was checked by NOD32 antivirus system. > http://www.eset.com > > --~--~-~--~~~---~--~~ You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to rctankcombat@googlegroups.com To unsubscribe, send email to rctankcombat-unsubscr...@googlegroups.com Visit the group at http://groups.google.com/group/rctankcombat -~--~~~~--~~--~--~---
[TANKS] Re: SSR go pop - the magic blue smoke comes out....
just to add, my drive wheel diameter is 16cm from outer edge of track pads, which if I assume the M01's can turn 350rpm at load, is 5.9MPH top speed --~--~-~--~~~---~--~~ You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to rctankcombat@googlegroups.com To unsubscribe, send email to rctankcombat-unsubscr...@googlegroups.com Visit the group at http://groups.google.com/group/rctankcombat -~--~~~~--~~--~--~---
[TANKS] Re: SSR go pop - the magic blue smoke comes out....
I hadn't actually started the climb, the tank was still a good meter away from the base of the "hill", but I was trying to go slowly, something which is proving difficult to do. With the tank on blocks I can confirm that I have the C6C and ESC doing proportional control as I can detect a speed difference between stick extremes, but on the ground it seems like it only goes fast, faster, and faster still. I had kind of assumed that *JUST* starting to move the stick would result in a "tankish" leisurely pace and it would ramp up from there as the stick gets moved further, but it seems like when the motors fire up at all, they are already going fast could I have something configured wrong? Or can the ESC not handle (provide) those severe slow speeds? > These two sentences probably provide some insight into the problem. If > you were about to climb a hill and you decided to "start slowly" (as > most people do when initially testing a vehicle), then you probably > *did* cause the motors to stall. --~--~-~--~~~---~--~~ You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to rctankcombat@googlegroups.com To unsubscribe, send email to rctankcombat-unsubscr...@googlegroups.com Visit the group at http://groups.google.com/group/rctankcombat -~--~~~~--~~--~--~---
[TANKS] Re: new progress
I now have the little fella moving and have posted a Vid on you tube , I have completed the spring suspension system since making this film as wheel 3 was fixed. and its very nice driving a tank having full suspension . http://www.youtube.com/watch?v=-DM7dT3Yxow Neil R --~--~-~--~~~---~--~~ You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to rctankcombat@googlegroups.com To unsubscribe, send email to rctankcombat-unsubscr...@googlegroups.com Visit the group at http://groups.google.com/group/rctankcombat -~--~~~~--~~--~--~---
[TANKS] Re: SSR go pop - the magic blue smoke comes out....
You might want to consider mounting your SSR's on a large heat sink. Paul H. - Original Message - From: "Modena" To: "R/C Tank Combat" Sent: Saturday, April 04, 2009 2:41 AM Subject: [TANKS] SSR go pop - the magic blue smoke comes out > > I was playing with C6C and ESC calibration, had the tank up on blocks, > and got it all working nicely, centered the joysticks yada yada > > then driving around a little in the garage, was about to do a climb > test, and she stopped dead. Control relays on the Anvilus SSR were > still clicking, but no movement. Shut everything down, started > everything up again, go to move, POP and the magic blue smoke came out > of one of the SSR's - now she still drives well, only in circles :( > > Anyone have any idea what would make an SSR go bang? I am using a > 60amp fuse before the SSR, motors are M01's. The tank had no > obstruction in its way, so its not like it was stalled. > > > --~--~-~--~~~---~--~~ You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to rctankcombat@googlegroups.com To unsubscribe, send email to rctankcombat-unsubscr...@googlegroups.com Visit the group at http://groups.google.com/group/rctankcombat -~--~~~~--~~--~--~---
[TANKS] Re: SSR go pop - the magic blue smoke comes out....
Modena wrote: > then driving around a little in the garage, was about to do a climb > test, and she stopped dead. > The tank had no obstruction in its way, so its not like it was > stalled. These two sentences probably provide some insight into the problem. If you were about to climb a hill and you decided to "start slowly" (as most people do when initially testing a vehicle), then you probably *did* cause the motors to stall. That is, if you didn't give the motors enough energy to start the climb, then they would simply sit there and start dissipating the energy as heat, which in turn causes them to become even less efficient. The slower you increase the power, the worst the situation gets until something pops. As others pointed out, in this case, the fuse was bigger than the SSR, so the SSR popped. This is one of the insidious problems with ESCs ... they allow you to more easily stall the motor. A simple on-off controller generates a large *but short* current spike when a vehicle initially starts rolling. Yes, the spike is large, but it is also short-lived, so the battery takes the worst of the abuse, not the control system. An ESC, on the other hand, allows you to draw lots of current for a relatively *long period* (as long as you hold the throttle on, but too low) which causes fuses and electronics all along the system to suffer. Keep in mind, electric motors *are not* like gas engines with transmissions. Electric motors try to provide the same torque at all speed levels and they will consume as much energy as possible to overcome a load. Gas engines and transmissions are strictly limited by their input settings and will not consume more energy than you allow them to have. ESCs can basically be split into two camps: those with internal feedback and those without. With internal feedback, an ESC can detect the situation described above and limit current flow to stay below the max design thresholds. In such cases, the ESC will either continue at a degraded mode or safely shutdown until it can recover (ie. you stop demanding too much from it). An ESC without feedback simply lets the motors consume whatever they want. The simple and inexpensive Anvilus design has no feedback. You might think that an ESC without feedback is a waste of time and money, but they do have an advantage in that they can be driven as hard as you want and, obviously, they can be made less expensive. The trick in using them is that you have to design the system and/or operate the vehicle so that you *don't* over-extend the ESC's capabilities. For example, in the Tiger, which has used an Anvilus controller in more battles than any other tank, the friction drive TTS tracks provides a natural relief valve ... the tracks will slip before the motor wants to stall. Furthermore, I've geared the drive train to provide maximum power in exchange for top-end speed. Finally, you'll rarely see me trying to go through harsh terrain or up hills with anything less than full power. Basically, I use the Anvilus controller like an ON-OFF controller that behaves in a more controlled manner when first starting the vehicle and when reversing directions quickly. You should also keep in mind that our vehicles and battlefield conditions are definitely on the "extreme" side of the spectrum. We torture the equipment like few other electric hobbies ... high loads for long periods of time in heavy terrain. Even the expensive ESCs are pushed to their limits and more than a few veteran battlers have cursed on the battlefield as their ESC has decided to safely shutdown or degrade performance. Regardless of what finally fails (cable, fuse, SSR, ESC, etc) your vehicle will be sitting there defenseless and you'll be upset. There is no silver bullet for reliability, no single part that can be purchased to solve the problem. You need to design, build and operate the vehicle to perform reliably. And, since everything eventually breaks, you need to design, build and operate the vehicle to be maintainable and easily repaired. That way, one break-down in the field doesn't ruin the whole battle, day or weekend. When it comes to our tank sub-systems (all of them), the single most important lesson to learn is "you can't over-engineer them". Sorry for you loss ... but it's far better to test it hard and break it in the workshop or proving grounds, then to let the opposing team find your weak point on the battlefield. Frank "Been There, Broke That" Pittelli PS: All of you considering building your own monster servo or speed control should read this article at least a couple times before proceeding with any design. --~--~-~--~~~---~--~~ You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to rctankcombat@googlegroups.com To unsubscribe, send email to rctankcombat-unsubscr...@googlegroups.com Visit the gr
[TANKS] Tank Overhaul
I've been watching some shows on the Military Channel called "Tank Overhaul" if you get a chance to see it, it's pretty interesting. They "restored" an Elephant on the last one at Aberdeen, evidently only 1 of 2 left in the world. Tom --~--~-~--~~~---~--~~ You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to rctankcombat@googlegroups.com To unsubscribe, send email to rctankcombat-unsubscr...@googlegroups.com Visit the group at http://groups.google.com/group/rctankcombat -~--~~~~--~~--~--~---
[TANKS] Re: SSR go pop - the magic blue smoke comes out....
Doug beat me to it. My M-01 motor set-up has popped my 70 amp battery breaker as well as 30 amp fuses going to the Victor ESC's when the motors have stalled. The M-01 motors can draw as much as 100 amps at stall. I would agree that the fuse was way too large. It should be under your device's max. Derek T065 On Sat, Apr 4, 2009 at 1:58 AM, Doug Conn wrote: > > I don't know why the SSR blew, but it doesn't make sense to have a 60A fuse > to protect a 40A SSR. You should use a fuse with a lower current rating. > You > may need to use separate fuses for each SSR. > >- Doug > > > -Original Message- > From: rctankcombat@googlegroups.com [mailto:rctankcom...@googlegroups.com] > On Behalf Of Modena > Sent: Saturday, April 04, 2009 2:52 AM > To: R/C Tank Combat > Subject: [TANKS] Re: SSR go pop - the magic blue smoke comes out > > > oh, and i should add the SSR's are Crydom, 40A 100V > > > > > --~--~-~--~~~---~--~~ You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to rctankcombat@googlegroups.com To unsubscribe, send email to rctankcombat-unsubscr...@googlegroups.com Visit the group at http://groups.google.com/group/rctankcombat -~--~~~~--~~--~--~---
