is there any video that helps to configure the TX12 throttle stick to both control the throttle value given to the motor driver and the direction in a way : throttle (0% to full reverse, 50% to stopped, and 100% to full forwards).
i think i will use logical switches and mixes
any help??
I think this question is the same you had before in the other thread.
What do yo wnt to do. You will configure your transmitter. If yes this don’t will work if you want to use your rover in any non manual mode as the FC does’t know any of the transmitter settings. It only see the receiver outputs.
So the mixing has to be done either in the FC-software or by seperate mixer between FC and your existing motor controller KAC-8080N
Suppose I only want to use one joystick for the rover’s skid steering (throttle left and throttle right). How can I configure this one?
These are the parameters that I have set in Mission Planner.
Servo1_Function: 73
Servo3_Function: 74
PILOT_STEER_TYPE: 0
Are there any configuration that I missed aside from these?
Please, show us what you want to do or to know and what ou have.
Out of your questions nobody can know what kind of rover with what kind of hardware you have.
In the first post you ask how to configure a transmitter but now you don’t anthers my questions.
Instead you come with a new qestion regarding skid steering.
How you want to realize a skid steering with only one joystick?
So which movement of the joystick should control what function?
.
I am working with skid-steer rover. but i am using one controller board for the right motor and one for the left.
each controller has an input for the throttle value as analog input between 0 and 5V
and one relay input for the brake. and one input for the FWD/REV direction.
the controller used is : KAC-8080N
I want to use an ardupilot in this application example: pixhawk4
i want to control the rover by using one stick like driving a car. the problem is the driver that accepts throttle and direction. so the outputs from the ardupilot must do that.
you only provided again same information as before.
And this mean the answer will be also as before.
No flightcontroller can control this specific motor controller directly. The reason ist the anlogue input to the motor controller between 0 and 5V. All flightcontroller don’t have a direct anlague voltage output. You need a converter from PWM to anlogue voltage.
Also you need to produce more than one outputs out of one channel (throttle and direction control)
Did you read the manual of your motor drivers carefully. FWD and REV are two independent inputs. With this inputs you not only controll the direction you also controll motor off if both inputs are open.
Brake input is a third switch also probably needed.
So again my question, how you want to control this with one stick. I assume it is a two function cross stick.
If the stick is centered the motor should not run or should it braked?
If the stick is moved straigth up the rover should move both motors full fwd?
If the stick is moved straigth down the rover should move both motors rev? .
If the stick is moved fulll left the rover should move left motor full rev and right motor full fwd?
If the stick is moved fulll right the rover should move left motor full fwd and right motor full rev?
What should happen if the stick is in the upper left corner?
It might be possible to implement this functionality with LUA script. Therefore you need a capable FC (eg. with H743 chipset)
hi [Juergen-Fahlbusch],
thank you first of your patience.
the problem of the compatibility between the PWM output from the FC and the driver analog input (0-5v) is solved by using a PWM to analog converter. i have chosen one that contains also relays to control the FWD/REV and BRK. the control of this relays are done by using the outputs of the FC.(AUX pins).
for that i supposed that mode: “brushed with relay” will work well in this case. and the servo outputs 1 and 3 will give pwm signals to control the throttle_left for the left motor and throttle_right for the right motor. and i configure two relay output pins for controlling the (REV/FWD) pin for each motor and one relay for BRK (given for the two drivers at the same time).
now i have explained in this reply the details for configuring the FC and its outputs to the driver.
is that clear for this time?
before i reply to you and explain the problem of confuguring the rc transmitter.
the PWM to ANALOG converter used:
if i want to use two sticks to control this type driver for each motor.
i use the left stick vertical axis to control the left_throttle and i do a mix in the RC transmitter to give 100% on another cannel if the stick goes up to control the relay that gives 12V to the FWD pin. if this stick goes down i give a signal to the throttle_left and zero to the relay (giving the 12 V to the REV pin)
same for the right stick that control the right motor.
if i want to go forward i move the two sticks with the same level to up. if i want to go right i move the left stick more than the level of the right stick, so the speed of the left motor is higher . the motor goes to the right.
is that seems to work well?
if yes . the task now is to control the rover using one side of the sticks as you indicated in your first reply to me.
If the stick is centered the motor should not run or should it braked? the rover should not move / we can brake it by overwriting this case to another channel that controls the relay opening BRK.
If the stick is moved straigth up the rover should move both motors full fwd? YES
If the stick is moved straigth down the rover should move both motors rev? .YES
If the stick is moved fulll left the rover should move left motor full rev and right motor full fwd?YES
If the stick is moved fulll right the rover should move left motor full fwd and right motor full rev?YES
What should happen if the stick is in the upper left corner? THE motor will move to the left with full throttle speed on the right motor and zero speed on the left one. as if there is a mapping of the two axis (vertical and horizontal ) to the two inclined axis (movement )
as the picture
Ok, now I get your point.
- any mixing on RC transmitters in conjunction with FCs is worse, because this only will work in manual controlled modes but not in automated (FC assisted) modes.
- for your converter module you need 4 PWM outputs.
But in skid steering mode of the FC has only 2 PWM outputs for the motors and additional 2 relay outputs for FWD/REV.
Servo1_Function: 73
Servo3_Function: 74
Relay5_Function: 5 (Bushed motor reverse 1 throttle-left)
Relay6_Function: 6 (Bushed motor reverse 2 throttle-right)
PILOT_STEER_TYPE: 0 - your KAC-8080N has two seperate inputs for FWD/REV. Be sure that only one at a time is closed. Otherwise the controller goes in an error stage. Also toggling the inputs while the motors are running with full load can cause mechanical damages and electrical overload situation.
1 - i did not understand carefully this point but i think it will not cause any problem for me because i am working in manual mode only
2 - i have taken care of all these parameters except the one considering the relays.
i think that using Relay5_Function and Relay6_Function : 1 (relay) is right and you said that their values must be 5 and 6 respectively. what is the difference?
in your case is there additional setup for the RC channels in adittion to throttle_left and throttle_right.
also 2 - i think i need an rc output for controlling the relay related for BRK?
also 2 - you said : " skid steering mode of the FC has only 2 PWM outputs for the motors and additional 2 relay outputs for FWD/REV."
i will use two converters : 1st contains ( converter for the throttle left signal + relay control of the left driver REV/FWD choice ) + relay for controlling the BRK in the two drivers.
2nd contains (converter for the throttle right signal + relay control of the right driver REV/FWD choice )
3 - “your KAC-8080N has two seperate inputs for FWD/REV. Be sure that only one at a time is closed.” for that i am using a relay the gives 12 V either to the FWD or to the REV. as i undertand from the datasheet of the controller.
also 3 - “the problem is the driver that accepts throttle and direction. so the outputs from the ardupilot must do that.” how can i be aware from this problem case??
thanks my friend for spending more time with my questions.
to 1) if you only run in manual mode with mixing on RC transmitter side as you said, why do you want to use an additional FC?
to 2) if you use a relay as shown in the schematic the motors run either FWD or REV but you have no motor off position. This might be ok if our anlogue speed controll input 0 to 5 V is really going to stabil 0.00V. If there is a small offfset the motors might start to run.
This topic is bizarre. What’s the use case? Do you just want a big remote controlled vehicle? If so, you are in the wrong place with the wrong hardware.
If you do want an autopilot for some level of automation, logging, or assisted/precise control, your approach is in serious need of improvement.
thanks my dear
i hope that you answer me the following points in the previous reply.
1 - i did not say that i want to use another FC . ia want to use two motor drivers with two pwm to analg converters
2 - i think this case “stopping the motor” can be done by the BRK or by 0 V at the throttle . this need some expirements later on the real robot
yes i want a big remote controlled vehicle. why you consider i am in the wrong place. i want to use the features of the ardupilot to control the motor drivers instead of designing an embedded circuit containing a microcontroller and programming it.
“your approach is in serious need of improvement” can you discuss me in details?
ArduPilot has no features to control the motor controller you have chosen, so adding an autopilot just increases complexity and solves zero of your problems.
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You above linked UU Motor Retail converter is doing the job to convert the receiver PWM outputs to the motor contoller 0-5V inputs and also the switches. Therefore if you only want to remote controll your vehicle no FC (flight controller) is needed.
If this small and cheap controller is as good as the description says I don’t know
the link between the rc transmitter and the pwm to analog coverter is the autopilot . for that i want to use it , else where what is the setup used instead?!.
If you read the decription of the pwm to analog converter carefully you see that this can be directly connected to the RC receiver. No FC needed. Also just for a camera output and telemetry no FC is needed as long all is just manual controlled as you said.
The FC is needed if you whant to run some stabilized or outonomous functionality.
This small board as mentioned above has the capability to control 2 motors and 2 switches or relays.
Yes, with a FC between the RC receiver and these control board you can do much more but in that case have to do also all mixing in FC and not in the RC transmitter as you said somewhere above
ok that is clear now. suppose i want to use the FC now , for later autonomous tasks.
the question about how to set the RC transmitter in the following manner (as in the picture) . that allows me to control all the vehicle with one stick (2 channels).
in a previous posts , some where you said:
set the two servo outputs to left throttle (73) and right throttle (74), leave PILOT_STEER_TYPE at default (not “two paddle input”), interchange the channel numbers for RC_MAP_THROTTLE and RC_MAP_PITCH, so the throttle bar in RC calibration moves with the right stick up/down. This should get the RC setup working right.
is that enough ???
Sorry for the delay
But i only have an ESP32 based FC I first had to implement a simple GPIO (Relay) function to the firmware of this board.
So in principle it is possible to control your KAC-8080 with “brushed with relay” function.
With this function you have two outputs which has to be connected via additional electronic to the KAC-8080 controller
- a PWM channel (eg. 1000-2000 ms)
- a GPIO channel to control a Relay
As you have two of these KAC-8080 controller you need at minimum 4 outputs on your FC
If you want to control this with just the right stick of your RC-Transmitter following settings needed:
- ARMING_RUDDER => 0 (disabled) //with your rover you want to execute “donuts”, full left or full right steering with your throttle stick at lowest value. For arming / disarming you need some other function
- MOT_PWM_TYPE => 3 (BrushedWithRelay)
- RCMAP_PITCH => 3
- RCMAP_THROTTLE => 2 //so that both throttle and steering is on the right stick in case of normal (MODE2) RX Transmitter.
- RELAY1_FUNCTION => 5 (Brushed motor reversed 1 throttle or throttle left)
- RELAY1_PIN => one of your free GPIO possible channels e.g. AUXOUT1 (50)
- RELAY2_FUNCTION => 6 (Brushed motor reversed 2 throttle right)
- RELAY2_PIN => one of your free GPIO possible channels e.g. AUXOUT1 (51)
- SERVO1_FUNCTION => 73 (ThrottleLeft)
- SERVO3_FUNCTION => 74 (ThrottleRight)
The above mentioned UU Motor Retail board is with these settings not or only partly useable as it requires 4 PWM channels as input but this cannot realized by a generic Ardupilot FC for the normal SKID Steering. Maybe this board also can be used with only the two inputs P2 & P3 connected but not sure. Instead you can use two seperate RC PWM to DC 0-5V converter like e.g. PWM PPM SBUS to 0-5V converter module - UU Motor Retail. But in any case you need a special RC compatible DAC as other small DAC boards for microcontrollers are using PWM range from 0 ms and not starting at around 1000ms to represent 0V output.
For the relays you also need a small driver stage depending on your selected FC as the output pins are limited on the current.
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