Opensource Remote / BMS / BEC

fuelre

10 mW
Joined
Mar 11, 2015
Messages
31
Hey guys

First of all sorry for my poor english, i hope evereybody understand what a mean/want.

I´m Patrick from Austria and I study elektonic

I dont like the current remote solutions like Wiiceiver or a car remote because they are not made for a Eboard!
Thats the reason why i designed a new remote with a bidirecitonal comunication that includes a BMS during the last week.


Now I want ideas form you to improve it.
This is a first version, there are maybe faults in it.
what extras/gimmicks do you want?


The whole stuff is designed to work with a standard ESC or a VESC
standard ESC: PWM output
VESC: connection through I2C or USART

REMOTE
Nunchuck Design
3D printed
18650 cell powersource (USB recharable)
NRF24L01+ transceiver
2 axis Joystick (only one axis in use)
128x128 pixel Display
Cruise controll Button
2 buttons and an incremental encoder for the HMI

Tech Spec:
Controller: Atmega328
Display: LS013B7DH03 Sharp
Joystick: same as in the Nunchuck
USB Charger: MCP73831

REVEIVER / BMS / BEC
90x50x15mm
2 stacked PCBs
- one with the Receiver, BEC and Switches
- one with the BMS
3 Switches (max 3A) for Front/Rear ligth and an extra channel (PWM)

Receiver:
Controller: Atmega328
NRF24L01+ as receiver

BMS:
LTC6803 (supports LIFEPO4 Cells)
Aktive Balancing
with his own small Controller
Always ON/Standby and self powered from the Battery

BEC
5V/3A by LM2576HV (Controller and Front/Rear lights)
3.3V/100mA (for the NRF24l01+)

PICS
Remote_1.PNG
Remote_2.PNG
Remote_3.PNG
Remote_case.PNG
BEC_RX.png
BMS.png

estimated Price for one unit:
Remote Case: 30€
Remote Hardware: 30€ (display 17€)
BEC:12€
RX: 10€
BMS: 35€

if we order more, its getting cheaper


What´s your opinion? What is good / bad / to improve?
 
Looks really good.

Here is my honest feedback.
- the BMS, BEC, RX being integrated is not a good idea. Some people will just want the RX. You should make it seperatley.
- the price is too high. I think the target price of a remote control should be $49.95 usd. This is for both the RX & TX.
- the LCD screen is COOL.... but not a "must have" feature for me. Suppose it depends what data is displayed.


Overall very good.
 
It looks great, will you do a kickstarter?

I would drop BMS and BEC, or keep it optional

The rotational encoder and screen is at a strange place, touched by palm of hand.
Could you move both to the left side, at least the encoder?
 
Thanks for your feedback onloop.

I know the price is high, but this is the price for one single unit. If we order for example 10 units, the parts are at least 20% cheaper.
The design for the BMS/BEC/TX is modular.
The BMS is not fixed, it is stacked onto the BEC/TX PCB and it is possible to cut the BEC along the yellow line away.
You can change for example the BMS PCB to a smaler one because you have only a 6s system and there are a lot cheaper BMS chips. The only one thing that it needs is a I2C channel.

some informations for the display are battery voltage, distance, change settings (particular with a VESC), ...

@erwincoumans

nope this is a projekt for this comunity, its not my mind to make money with it.

the encoder is there because i want a remote for bothe hands - exactly like the nunchuck. If the encoder is on the side you always touch them with your fingers.
 
fueire, looks good so far. I had two smd NRFs for my remote for a while, and that is not perfectly reliable either unless placed carefully. What I did was replace the receiver with a NRF + PA module with an external antenna. I think the antenna is what makes the difference here. This made a huge difference in range and has been working perfectly for me without any glitches whatsoever. Maybe you should consider replacing the receiver with an NRF module that has an antenna. The PA is probably not needed since the TX in the remote has no PA. Even better would be to have a proper antenna and PA in the remote as well, but that takes space and draws extra battery, which is why I only use it on the RX, which is more than good enough anyway.

I had a look at the LTC6803 chip, and it looks nice. One of the things I have been missing is an easy-to-use charger. With that chip and some other electronics, I would like to make a charger PCB that can take 10V - 30V DC input and charge/balances the battery pack. Then I can just plug in a laptop adapter / car 12V cable etc. to charge my board instead of unplugging the batteries, connecting all balancing connectors to a balance charger and so on. I think I can make the charger quite powerful and with configurable output power based on how strong the power supply is. With enough power, charging the batteries in one hour or less should be possible. If a smaller supply, such as a laptop adapter, is used the charging power can be decreased in software to not overload it. I have built some DC/DC converters before, so I'm sure that I can make a nice and compact charger that can be integrated on a longboard. This would help make a nice enclosure for the batteries and get rid of many cables. Does this sound interesting?

I think what is really missing today in the DIY scene is a nice controller. For me it would be a GT2B inside a Wii Nunchuck.
PWM is bad and limited, even if the connection between the controller and receiver is limited. Better would be a nunchuk with a reliable connection, like the modified one I have at home :)
 
Hey Vedder

i hobe i dont forget to answer one idea ^^

The idea with the NRF PA version is good. i placed my NRF module in a direction where i can use one of the PA version to. The PA version has the same pinout, it is just a bit longer. If i use a 18650 2500mAh battery at the remote 100mA more is a lot but it doesn´t kill the On time to zero. simply charge the controller at a USB port if you are charge the Board.

Yes that sounds realy good! My next step is also a Charger. The main problem are the 50V - there are a lot easy to use charger ICs up to 30V systems (i have a sample here because i use atm a 6s system, the PCB is in order)
The current way what I am thinking about is a LTC4020 / LTC4000 or LTC3796. Take a lock on it.
The idea with a Laptop power supply is cheap but slow, because the supplys deliver not enouth power - a 12S 5Ah requires 250W or at 12S 10Ah 500W. The biggest laptop power supply that I know have only 200W and thats a monster for a notebook.
But I am sure you know that already. :D
And powersupplys with more than 300W costs at least 50€ at Mouser.

But now its time to develope the new Remote.

i added a PWM/servo signal for standard ESC like mine (Alienpower 8S TWIN), but there are already I2C or USART (CAN doesnt support my Controller) to comunicate with your greate VESC or reverse

Another idea is to use your base with your controller for the nunchuk and I add my stuff (display, BMS, switches for lights) that i want. But I have never worked with ChibiOS or STMs. Do you know a good tutorial to start with it?
I saw there is a Chibistudio.

@torque:
do you mean my work or Vedders work :D
 
fuelre said:
Yes that sounds realy good! My next step is also a Charger. The main problem are the 50V - there are a lot easy to use charger ICs up to 30V systems (i have a sample here because i use atm a 6s system, the PCB is in order)
The current way what I am thinking about is a LTC4020 / LTC4000 or LTC3796. Take a lock on it.
The idea with a Laptop power supply is cheap but slow, because the supplys deliver not enouth power - a 12S 5Ah requires 250W or at 12S 10Ah 500W. The biggest laptop power supply that I know have only 200W and thats a monster for a notebook.
But I am sure you know that already. :D
And powersupplys with more than 300W costs at least 50€ at Mouser.
My idea was to simply make a current controlled boost converter using one or two FETs (depending on if it is synchronous or not), an inductor and a MCU to run the control loop. Then the whole charger logic can be implemented in the MCU. It might be a bit more work for coding than using an off-the-shelf chip, but it is not that difficult and the configurability makes up for that.

Regarding the power supply, I can use the same one I have for my hobbyking charger which also is from hobbyking. A light laptop charger that I can carry in my backpack that gives a charge time of 3-4 hours is also sufficient. When I'm done riding, I will probably not use the board for the next 4 hours anyway.

fuelre said:
But now its time to develope the new Remote.

i added a PWM/servo signal for standard ESC like mine (Alienpower 8S TWIN), but there are already I2C or USART (CAN doesnt support my Controller) to comunicate with your greate VESC or reverse

Another idea is to use your base with your controller for the nunchuk and I add my stuff (display, BMS, switches for lights) that i want. But I have never worked with ChibiOS or STMs. Do you know a good tutorial to start with it?
I saw there is a Chibistudio.

I use eclipse with makefile projects. It gives auto completion, indexing etc. Setting up the toolchain is easy on ubuntu and chibios has good documentation and examples. I think you will be able to build and modify my nunchuk code in no time. If you follow my VESC tutorial, you will be able to build the nunchuk code right away.
 
The coding/programming/components talk is going over my head, I'm the physical design sector instead, but I feel enertion is spot on the money.

Not everyone wants a bms/bec/intelligent controller. Many of us are, and will for years, use lipo batteries and simply want a "dumb" controller like the gt2 are. These can be smaller, more easily used, not cluttered with additional features, lighter and more robust. I want a throttle, maybe aux, on/off, trim, power level. Combine that with a small lipo and that is perfect. USB charge it on your desk, stick it in your pocket, small enough to fit a compact housing that works with gloves, and you are good to go.

I was looking for the link to the remote stuff I saw that had these before when I found this actually. Anyone know the link for that? Wanting the smallest, simplest, USB charged lipo controller possible. I feel that is what will get people too - maybe have it modifiable via smartphone for easy usability (eg. swapping between trainer/advanced power, tweaking brake power...)
 
@fuelre: would be nice if the BMS could handle both 1x12s or 2x6s battery connectors. It might be not so easy to modify the PCB for this..
 
@ vedder:
i prefer a hardware solution, because its a faster refulation and more reliable.

what is your powersupply rated?

I took a look on Chibistudio and the samples for my nucleo board worked, but i have huge problems to implement my segger j-link, and i have no idea how to create a makefile for the stm32f103 which i wana use for my remote.
Maybe i give them a second try in the future.
My first version with the Atmel controller works already on my bench.

@ bandaro
as i wrote is the whole stuff modular, but i undrstand what you want.
It is definitely possible to create a smaller RX, which includes only the throttle.
what do you mean with "aux"?

please create and share a possible case for the controller - we dont need a lot of space for the electronic components. The biggest problem is the trigger. If you know a way to create a small trigger please tell it to us.
The other thing is for example the cruisecontroll button on the wiiciver - i miss it every time I use another remote that doesnt have this function.


@ pf26:
what exaktly do you want?
an extra pin to connect 2 6s batterys without an adapter?
this is possible with an extra row for a connector with one more pin.
 
vedder said:
My idea was to simply make a current controlled boost converter using one or two FETs (depending on if it is synchronous or not), an inductor and a MCU to run the control loop. Then the whole charger logic can be implemented in the MCU. It might be a bit more work for coding than using an off-the-shelf chip, but it is not that difficult and the configurability makes up for that
.

VESC consists of:
MOSFETs
MCU

Use motor coils as inductor or connect external inductor together with input power cable.

Some reconnections will be necessary when charging but with smart designing of cables it shouldn't be an issue. See also the Russian adappto (spelling?) e-bike controller. They have a setup like this.
 
fuelre said:
an extra pin to connect 2 6s batterys without an adapter?
this is possible with an extra row for a connector with one more pin.
Yes, the idea is to avoid the adapter. I imagine several people use 2x 6s and the more adapters, the more issues.
So it was just a proposal for you to modify the PCB to support both options, but it does not seem so easy to do.
 
Hey pf26

2x6sConnector.PNG

here you can see an easiely solution - you need a bit more space because the pins are now longer than the board.
you use the left connector if you want a 12s system or the right con if you want 2x6s (the connector is only copied - i know that there is one more pin required)

Do you know what i mean?
 
I made some progress.

The encloser für the remote is in order and my first "prototype" is ready to hit the road.
unfortunately my motor is broken and i cant test my remote now outdoor, but it works great on my bench- the remote works through 2 concrete walls

At the moment there are the charging circuit for a samsung icr18650-26f, on/off switch, the controller with the NRF and LEDs/switches on it.

IMG_6899.JPG
 
why isnt the picture visible?


I got my 3D printed parts:

The parts are not perfekt printed, so i had to do some extra work with a scalpel. But after that it fits perfektly together.

The location of the Cruisebutton and Trigger is perfekt. And the other componentes are fits also well.
But the whole case is a bit to big - espacialy at my middlefinger on one of the pictures.

View attachment 5
IMG_6942.JPG
IMG_6941.JPG
IMG_6940.JPG

I made with the new inforamtions a new version of the remote.
The main improvements are:
+ modified shape for easier print
+ smaler case - now 25mm and not anymore 44mm wide
+ cruiscontroll button is now on one PCB with the trigger
+ changed display because the old one is to big to fit in a 25mm case

Remote_V3.JPG
Remote_V3_open.JPG
 
Just a short information:

I made a fast sketch for a evolve similar remote after some talking to whitepony:

It uses the same components as my V3 Design.
I know that the Battery is to big, but I can´t find a good, small and cheap replacment for it - is there somebody who knows one? (a 18650 cost around 2$ for 2500mAh)
Maybe this is an alternativ design für some people

Remote_V3.1.JPG
 
it took some time but here are some news:

The new V3 PCB is assambled, but its not nice to programme/develope it only with a programmer - i ordered a debugger that arrives hopefully next week. slow german shippig -.-

You can break down the trigger PCB for another placement in a Case.
The battery is in a holder because i didn´t printed a new case till now.
The powerswitch and the Programmingpins are temporary for developing (they didnt fit inside the Case)
I mount and programm some functions for the display when the rest works well.

some Pics:
View attachment 1
V3_PCB_2.JPG

I post the whole specs when the new debugger is here.
 
thats a difficult question - I had the most parts already in stock

a quick out of mind answer for one unit:
2€ Controller
2€ FTDI UART-USB
2€ NRF from china
1€ Joystick
2€ Bat (standart 18650 cell)
8€ PCB
5€ other peaces
~25€ plus 15€ for a 3d printed Case (13€ extra for the Display)

But these are the prices for one Unit - espacialy the PCB price drops
 
That looks very nice.

If one was after a "dumb" controller that only had the throttle, trim and on/off, would this be a plug and play option for a gt2B replacement?

I literally just want a controller that will speed me up and slow me down. I have a printer plus concepts for controller housings, and looking for a compact internal system to use. Your system with a potentiometer to replace the joystick (so it's a single axis motion) and a USB rechargeable 18650 would be brilliant if it's something I can plug in, trim the throttle and ride away.

If it fits the above, how long before I could get the system? I will design and make a controller housing myself for it anyway, but will need the electronics and it all programmed up from you.
 
Instead of the larger 18650, what about a small lipo in the range of 900-1000mAh?

Here's a small 900 nano-tech round lipo:
900nano-main.jpg

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=23318
only 12mm x 58mm.

Obviously a compromise on capacity, but 12mm vs 18mm compared to the 18650!

What's the use time on the 2600mAh 18650 expected to be?
 
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