Good Morning Everyone,
I came across a couple pieces of hardware I am going to utilize in my R2-D2 Project. I was wondering if anyone has seen these, and if there was any scripts written with ARC for this hardware. I am going to use the Arduino DUE & UNO Hardware:
16-Channel 12-bit PWM servo shield I2C interface PCA9685 Adafruit-Compatible
16-Channel servo Shield
Using only two pins, control 16 free-running PWM outputs! You can even chain up 62 breakouts to control up to 992 PWM outputs
It's an i2c-controlled PWM driver with a built in clock. That means that, unlike the TLC5940 family, you do not need to continuously send it signal tying up your microcontroller, its completely free running!
It is 5V compliant, which means you can control it from a 3.3V microcontroller and still safely drive up to 6V outputs (this is good for when you want to control white or blue LEDs with 3.4+ forward voltages)
6 address select pins so you can wire up to 62 of these on a single i2c bus, a total of 992 outputs - that's a lot of servos or LEDs
Adjustable frequency PWM up to about 1.6 KHz
1PC 8 Channel Obstacle Avoidance Infrared Detector Tracked Sensor Module NN
8 Channel Infrared Detector Shield
8 Channel Infrared Detector Tracked Photoelectricity Sensor
A smart car or robot hunt (including black and white lines), walking along the path of the black line, also known as tracing.
Smart car to avoid the cliff, anti-drop.
Smart car for obstacle avoidance
Upgrade to ARC Pro
Unleash your creativity with the power of easy robot programming using Synthiam ARC Pro
Do I apply 7.4vdc to an external board that the servos connect two wires to and the third control wire goes to the EZB?
If you want to start moving 10 servos at the same time, it would probably be best to provide some of them with a separate power feed. If you can start moving 3-4 of them, then start a couple more, then a couple more, you could easily handle this by connecting them directly to the V4. I don't know of a robot out there that has to start 10 motors at the same time, until you get into walking robots and they don't have to start 10 motors at the same time, but it could be possible I guess. I would seriously doubt that an R2 would need to do this, but I guess it is possible.
If you wanted to provide separate power feeds, This could be done from the same power source, but by bypassing the V4 if you are using a power source that can provide enough amps to move all 10 servos + whatever load that there is for other components you are operating.
If you are running an external power source for the servos, you must have a common ground (black or brown wire normally) to the ez-b and the device. This could be done by running the black wire from the V4 to the device. You also have to have a signal (white or yellow wire normally) to the white port on the EZ-B. The red wire from the servo would be connected to the power source's red wire or positive terminal. If you are using one power source for everything, you would have a common ground and you would be able to run the white or yellow wire from the servo to the EZ-B's white digital port and the red and black (or brown) wires to the power source.
What is the maximum amount of amps the EZB v4 would be able to handle from the external power supply? I think mine is a 12vdc - 12.5amp supply.
The v4 can be powered by 200 amps if you want. It can only draw 20 amps before the fuse in the power base blows or the polyfuse flips. If you had a need for a lot of amps, I would recommend bypassing the V4 for power to these devices.
The other consideration in your scenario is the amps allowed by the regulator(s). They have a limited number of amps that they can provide. Linear regulators waste a lot of power. Digital or bec/ubec regulators can provide far more efficient power.
Maybe Richard R can chime in on where he got his? I have his old battery so I don't know where it originated. But they're great and last a long time.
Voltage regulators are too high maintenance and generate a lot of heat.