Extended-BLDC-Tool with Watt Control Mode, PPM Cruise Control, Separate Throttle Curve and Android Apps3 weeks, 3 days ago | 0 Replies
I want to use the modified firmware to represent my modified BLDC tool. The main objective of this modification is to maximize the control of the board of directors. Because I don’t like that, I can only use 50% of the throttle at higher speeds. The second important idea was to use my mini remote control for cruise control via PPM. Just because it’s possible. After a period of fine-tuning, I found that I needed to adjust the throttle curve to fully control the power board.
So here are the features:
Finally, Watt mode is designed to give you more control at higher speeds. At first, you thought VESC would have less power, but then you learned that you only need to pull the trigger a little. As you begin to sculpt at a higher speed, you will definitely feel the difference. Another advantage is that when you set the watt limit (motor setting), the power of the entire battery capacity feels the same.
Watt control has three new control modes:
Watts with brakes without reversal (recommended) (Nunchuk also exists) Depending on your “Max Motor” and “Max Battery” Settings, you will release the throttle range at higher speeds in “Current Control”. With watt control, it has the advantage that it can use the full throttle range at any speed. This makes the board much easier to control, especially if you prefer to sculpt at a higher speed. This works at any speed as long as the motor is set at this speed to allow so much power. Of course, near the maximum speed (motor KV), the motor’s efficiency can no longer produce this power. But you can set the true maximum in the motor Settings and define the power you want here. As a result, programming beginner mode with 250 watts of power is very easy. The maximum wattage that can be achieved is defined by the “Battery Maximum” in the motor Settings. You can calculate it in terms of 3. 6V one battery * series battery * maximum battery. For example, a 10S4P battery with a maximum battery setting of 25A is 3.6V * 10S * 25A = 900 watts. You can limit the maximum wattage in the motor setting, which is explained further in this article. If no limit is set, then it calculates the maximum wattage from the actual battery voltage. For example, the maximum attainable watt is 1000 watts. Then 30% throttle will be 300 watts, 50% throttle 500 watts, 80% throttle 800 watts and 100% throttle 1000 watts. Maximum up to 1000 watts. Then 30% throttle will be 300 watts, 50% throttle 500 watts, 80% throttle 800 watts and 100% throttle 1000 watts. Maximum up to 1000 watts. Then 30% throttle will be 300 watts, 50% throttle 500 watts, 80% throttle 800 watts and 100% throttle 1000 watts.
Watt (Nunchuk also exists) “Watt” control mode works like “Watt No Reverse Brake”, the difference is that you also have the reverse. The only problem with the standard astern function is that when you apply a hard brake, the wheels may start to spin backwards as you continue forward. To avoid this, I added the parameter “Enable the maximum ERPM for the direction switch”. . When this feature is enabled and the brake is applied hard, the brake will work like “Watt with No Reverse”. To drive backwards, you must release the throttle and brake again. But this only works if you are below ERPM (4000 in the figure). If you are above it it will brake normally again. When you drive backward and the backward direction exceeds 4000 ERPM, it will accelerate backward and will not brake. If you fall below 4000 ERPM backwards and you quickly accelerate forward and brake again, it will enable normal braking again. To reverse, you must release the throttle and brake again. How do I find the perfect ERPM for this parameter? Better to go down the mountain. Then apply the full brake. You will see that the motor cannot stop the board from moving at very low speeds. If this value is set correctly, you can now release the throttle and brake again and the motor should begin to accelerate backwards. If this is not the case, the value is too low. In my tests, the 4000 ERPM worked fine. For most Settings, such as 4km/h.
This sounds complicated, but it becomes very intuitive after a while. If you don’t need it to reverse, then simply use “Watt no reverse with Brake”.
PID speed control without acceleration This mode is experimental, as it only activates cruise control and maintains speed when you press the throttle. The brake is working normally. So there’s no acceleration. This may help legitimize the board of directors in some countries/regions.
Traction control offset
The problem is that standard firmware always reduces the power of a VESC when traction control is enabled. Because the VESC RPM reading is not very accurate, it may be off by ±400 RPMS. This means that at 500 updates per second, the current in the VESC bounces back a lot. ALOS When you do a curve, the inner wheel is slower than the outer wheel. As a result, the outer wheel will gain less power, resulting in power steering. To prevent this, you can define an offset at which VESC should not reduce power and provide the same current to both VESCs. Beyond this offset, normal traction control will intervene. If you set it to 3000 in most Settings, this will not enable traction control if the speed difference between the two VESC is less than 3km/h. So traction control only reduces the use of power when it is really needed.
The PPM pulse can be precisely adjusted by the central position
This will adjust the center position to the actual value. From that position you can adjust the maximum throttle value in both directions. So you can use the full throttle in both directions. With standard firmware, in most cases not all throttle ranges can be used in one direction. Again, this gives you more control and sensitivity. If you don’t know how to set the pulseWith value, you can use the automatic wizard, which tells you what you must do. It is a good idea to disable control mode before using the wizard. Otherwise, the motor will start to spin (not the real problem).
Use the maximum wattage limit
To limit the maximum wattage of motor output, you can enable Use Maximum Wattage Limit on the Motor General TAB and define a wattage limit.
Importantly, you must perform this operation separately for each motor, master motor and slave motor. If you set this value to 1000, 25% of the throttle will be 250 watts and 100% of the throttle will be 1000 watts. Of course, the throttle curve has an effect. The maximum battery value has a higher priority, so if the maximum battery value is set to 10A and your battery is 36V, you can only generate at most 360W. If you set this value to 1000 watts, then you can only use 36% of the throttle, since the battery maximum will prevent higher power output later. So just make sure the battery Max allows VESC to produce that many watts. You can also use this parameter to easily limit the power output of VESC so that children can easily board.
The gas curve
You can define the throttle curve here. You can define three different points along the throttle curve for braking and acceleration. When you change the value through the box, you will immediately see the difference in the diagram. This is very intuitive and easy to understand. Always use these three values and do not try to set them to the same value as another location. This means not to set the same value for two or three boxes. Always choose meaningful values. It is suitable for watt, current, PID and duty cycle modes. If you use the ERPM limit, it is also the watt reverse. It only applies to acceleration. The brakes are the same as usual.
Here you can see the result of the throttle curve adjustment. The Y value is used to define the percentage of power to be used and the X value is used to define the throttle position. So in the picture, you see that the braking curve is normal, and the acceleration curve uses 12.5% power at 25% throttle, 30% power at 50% throttle, and 60% power at 75% throttle. Using the edge sharpness factor, you can make the curve rounder. But if you use crazy values, then the curve can get stupid. So be careful what Settings you use here. But you can always see what happens to the power output in the diagram.
Duplex cruise control via a steering channel connected to the second VESC:
The steering channel can be connected from VESC, and “Cruise Control via Auxiliary Channel” can be activated in the PPM setting. This enables cruise control when the throttle is not pulled and the steering channel is turning more than 30% to the left or right. In this mode, braking is always possible, just to avoid reacting stupidly at a shocking moment. Cruise control is also disabled when you pull the throttle, to avoid accidentally pulling the throttle when cruise control is activated, and then having a big surprise when cruise control is released. So I hope I can avoid a terrible situation. I recommend setting the speed control on the Advanced TAB to KP and KI to 0,00400, and leaving KD at 0,00000.
In the figure below, you can see that when you use the turn to activate cruise control, you have other options. You can define what should happen when the pulse width is negative (less than 50%) or positive (more than 50%). If you use motor Settings, the behavior will be the same as what you set in the Motor Advanced TAB. Otherwise, you can define whether to allow the speed controller to apply the brakes when you are going faster or not. For example, when you turn right, cruise control may not brake if you are too fast, and when you turn left, it does apply the brakes. This allows you to sculpt and go downhill using cruise control.
Tip: Most of the time, it will emit a lower signal when you turn right, and a higher signal when you turn left.
Disable cruise control interrupts
You can disable braking during cruise control using the parameter “speed controller allows braking”, because it is very annoying when you want to sculpt in cruise control. Anyone who has tried it knows what I’m talking about. The disadvantage is that when you want to maintain a constant speed on a downhill slope, if cruise control is going faster than when cruise control is activated, it won’t brake. BTW: I changed the cruise control in BLDC mode from duty cycle control to current control because it allows for smoother ride. When should the brake be disabled in cruise control, because you can actually turn off the motor. There are always small corrections and interruptions in duty cycle control, and these corrections are disconcerting.
So finally, before I upload my code to GitHub, it would be cool if someone wanted to try out the whole change. The modified BLDC-Tool only works in Ubuntu (no Windows). And you must flush VESC with the firmware I modified, or the BLDC tool will not work.
I have tested many modifications and I have not changed any of the safety features of VESC. So it should not blow up VESC in any way. But, of course, I don’t guarantee anything. Therefore, testing is at your own risk. But I think there are some brave members here.
(Only applicable to VESC hardware version 4.10 or later. Actual version 4.12 and VESC-X are fine.
If anyone wants to test it, you can download the file here. Windows BLDC-Tool, Modified Firmware, Ubuntu BLDC-Tool, and Android Apps 3.3K
App 450 in Google Play Store.
请注意，这仅适用于 4.10 或更高版本的硬件（VESC-X 也是如此）。
重要提示：您必须使用经过修改的 BLDC 工具来刷新输入。