Speed and Acceleration in Arduino

I have a Maestro Mini 6, hooked up and controlled through Arduino.

In the Maestro Control center, the range of motion is 1000-2000, with 1500 as center, but in Arduino I have to use 4000-8000 with 6000 as center, when using the Maestro libraries.

Now I am trying to decipher the speed and acceleration settings. In Control Center, speed allows 0-10000, and acceleration allows 0-255. The online reference for the libraries says I have to enter a number between 0-16383 for either speed or acceleration.

I need to know what the numbers are doing in Arduino with the library, so that I can set these more efficiently. Is there any clear information out there as to how this works?

Thanks
S*

Hello.

I am sorry for the confusion. The speed and acceleration values are a 1-to-1 correlation. If you send a speed value higher than 10000, it will be truncated down to 10000. Similarly, if you send an acceleration value higher than 255, it will be truncated to 255.

The reason the position value is different is because the Maestro uses units of quarter-microseconds internally, and the Maestro Control Center software shows the units in microseconds since that is a more standard unit for RC servo signals.

Brandon

OK, thanks.

I guess my biggest question is, how does the acceleration number work. What is the formula or how does the value affect the motion directly.

When using a speed or acceleration limit, the Maestro breaks a movement up into a series of smaller movements. The speed variable controls how much the position can change at a time. The acceleration variable controls how much the speed variable can change at a time. You can find a detailed description of how the speed and acceleration variables work in the “Channel Settings” section of the Maestro user’s guide.

Speed. This option specifies the speed of the servo in units of 0.25 μs / (10 ms). For example, with a speed of 4, the position will change by at most 1 μs per 10 ms, or 100.00 μs/s. Mini Maestro 12, 18, and 24 only: If you use a period other than the default 20 ms, the units of speed are different. See below for more information.

Acceleration. This option specifies the acceleration of the servo in units of (0.25 μs) / (10 ms) / (80 ms). For example, with an acceleration of 4, the speed of the servo will change by a maximum of 1250 μs/s every second. Mini Maestro 12, 18, and 24 only: If you use a period other than the default 20 ms, the units of acceleration are different. See below for more information.

Brandon