I changed it to Dshot600 (7) because my esc were beeping and wouldn’t start in ‘normal’ (0) but stopped once I changed to DSHOT. I couldn’t find another way to stop them beeping - it seemed to be a throttle issue according to hobbywing esc manual.
I see no evidence those ESC’s are Dshot capable, like most Hobbywing ESC’s, so change it back to PWM and troubleshoot from there. Are they configured for bi-directional operation (neutral at 1500µs), or can they be? ESC’s meant for vehicles, like other Hobbywing products, are by default.
For example the Brushless products on this page HW Brushless ESC’s
a very good point. To be honest I’m new to using esc’s and i was struggling to find out. Here’s the one I bought - https://wheelspinmodels.co.uk/i/300295/?gclid=Cj0KCQiAv8SsBhC7ARIsALIkVT3PHUjg_7QRPM5jq2ZUCd9QXuj4hH4F0Q8GKcAhKdGCK0omv2UTFsgaAr0aEALw_wcB
I found it hard to find an esc that was 8s capable. Also I’m using a xbox joystick which rarely settles at trim 1500 so I thought that might be causing the esc’s to go into safety mode as its receiving a input at startup.
Those are not suited to a vehicle. In the programming table I don’t see a Fwd/Rev mode selection.
Ah thanks ok. Would I have to go for a forward reverse esc that is capable of 8s (for a 24v motor)? I’ve looked into Vesc as they tend to capable of more load.
they have clockwise or anticlockwise option in the programming table. Is that not the same as forward and reverse?
The forward & reverse there is to allow reversing the motors, without rewiring, but is only a configuration event change. This is useful if the esc is built into a craft, and it is not easy to access the wiring, and you find, the props (or drive) back to front/wrong direction. Some esc’s give lower outputs for reverse than forward.
If the version of your esc has the 3 servo connector cables, each with signal, power and ground, then you have the option to change the motor direction, through a switch on the transmitter. (1 plug is standard esc to receiver, another is esc to reversing channel of the receiver, and 3rd is for the programming card. The esc looks to be ranged from 1000microsecond to 2000, in 1 direction, stopped at 1000, while the operation of the switch channel, then would actually reverse motor.
The choice and selection of esc to motors etc, is many and varied! Good luck.
No. You need brushless ESC’s for RC cars/trucks or at least an ESC with a bi-directional mode. Center throttle (~1500us) is “neutral” reverse is 1500-1000 and forward is 1500-2000 generally.
It’s much more common to use brushed motors and ESC’s on vehicles/boats.
What battery power are you using? Sounds like 6S capable should be fine.
What Dave says is very pertinent, and important.
You should also be aware how overly powerful your esc is compared to the motors. The motors are 8W, so at 24V the theoretic current is in the order of 0.3A.
Your ESC is nominally 24V 120A, so capable of 2880W!
Your esc may not be able to go as low as 0.3A, or even less with a high controllability?
Your component choices don’t make a lot of sense. Describe what you are trying to do and perhaps we can suggest something practical.
Hi guys thanks for all the help. I understand that brushed Motors are used more commonly but I want to use brushless as I’m planning to first prove that the pixhawk can control the rover the way i want on a smaller scale model (which is where I am at now), and then I’m planning to build a larger ‘farm rover’ which requires brushless motor wheels.
for the smaller scale robot I’m trying to control the brushless motors (specs described above) used in a ‘Yardforce 500’ mower with pixhawk 6c running ardurover. I want to control it using skid steering - so to do that I need 2 esc’s. The power supply is 8s (I’ve measured 27.2V) and the motors require 24V so I’m not sure 6s esc will be suitable. Thanks for all describing whats wrong with my ESC choice it makes a lot of sense - I’m definitely in the process of learning more about brushless motors. I’m not sure where to find an esc that is capable of 8s, 0.3A and with bi-directional mode. I know this should be completely possible but I’m struggling so if anyone could point me in the right direction that would be great.
You’re so right, but it seems if I want 8s capability I have to go up to 120A (2880W) which far exceeds my motor’s watt capabilities. I’m probably getting confused somewhere though.
What is the reason to go for 8S?
As your tests are going to be on a much smaller craft, could you add in a temporary, lower voltage supply, transformer or buck converter, to get you down to much lower voltages and powers, closer to matching your scale model power demands, and better chance to find a workable esc? The when the scale model functions well, revert to the higher load units, with bigger motors etc, on the full size unit?
Your motors are probably rated for 24V, but often the brushless motors can take quite a range of supply voltage, while 24V may be their top limit?
I personally use brushless motors on all my boats, currently 8, some single screw, 1 triple, most twin, excluding 4 more that are re-homed. Love brushless.
There are many car or boat esc’s for brushless, that include “bi-directional” built in, and reasonably priced too, that operate in the 7.4V or 11.1V areas, that can provide plenty of power, without going crazy on current loads. The reason I say car/boat is that both tend to be bi-directional as default, and the car market is bigger, so in theory cheaper, though cars tend to have braking facility, and boat can have water cooling. The advantage in temporarily lower volts, is that the options are much greater.
a vesc controller will do what you need, you need a FOC controller for robots like a vesc or O-drive that are designed to turn a motor slowly. most RC escs are square wave controllers that need a minimum speed of a few hundred RPM ro run smoothly. most robot application also use sensored motors, as you cant start a sensorless motor from zero RPM it will just chug until you remove the load and let it spin up.
The reason I’m going with 8s is because the yardforce 500 whose motors I’m using came with an 8s battery. Perhaps it was never using the full 24v when running. This tempts me to buy a 12v boat/car esc that’s more suited spec wise, but would that run the risk of them overheating or not being able to drive the motors?
geared brushed motors would be far simpler. brushless robot motors are quite specialised, you need the you need the right motor for the application and the correct controller for that motor. you cant just use any brushless motor and esc. aircraft motors are designed for high speed. even rc car motors run though a gearbox so they can spin fast. they are just not designed for high torque at low rpm.
Ok I’m wrapping my head around this. I think I’m going to step away from brushless for now. Instead I’m going to order a dual channel motor driver and two brushed motors as its far more simple to get up and running immediately. However, I’m going to continue the brushless research and try and come up with an esc system as I’ve now opened pandoras box into the esc world and it has peaked my interest. thanks for all the help everyone!
hoverboard motors are really good and you can pick up broken boards for peanuts, the v1 boards with the programmable controllers are getting hard to find how but you can still use the motors with o-droid or vesc.
I am guessing that you don’t still have the remains of the mower?
It would have had the right sort of speed controller, and a brain or controller, to make it all work?! If you can find out from Yardforce what controller and or esc, (may well have been a vesc too!,) then you might be able to rework into a replacement system? The mower should have had forward and reverse, to enable it’s autonomous activities. It would be disappointing if they had built it all onto one master board, as then its more of a problem to separate/hijack the parts. Good for experimenting.
As geofrancis has said, there are many more options. hoverboards, electric bikes, and brushed gear motors, etc…
I came back after reading this thread a day or two ago to suggest that the iFlight Blitz series of ESCs might work (80A, 12S, single or 4-in-1 packaging), but after catching up on the rest, that seems a bad suggestion.
If it were my project, I’d lean heavily toward a sacrificial VESC driven hoverboard as the power plant.
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