Finding a home position (using Hall sensors). This project needed a wide range of inputs and outputs, so has been done using an Arduino Mega 1280 board, although a Mega 2560 would do just as well. This includes the L298 unit, the encoder counter, various hall sensors for doing PEC and fuses and relays.
That is a fairly simple task.
Arduino can actually turn off the power to the telescope mount itself - handy when you detect an problem. The Arduino is entirely responsible for running the motors and pointing the telescope.
(In the interest of full disclosure, a year later (when I already had a prototype) I was able to find a fellow amateur astronomer who made OnStep Go To, but it was a computer aided solution and was not for me! If a slew is taking to long, or the telescope is moving to slowly, the Arduino will shut down the power to the mount and then go into sulk mode. It is not impossible that this may turn into a commercial project one day therefore I do not wish to share my entire source code. This system was extremely slow, underpowered and unreliable.
At the heart of the system is a pair of Maxon Motor precious metal brushed coreless DC motors with 512 cpr encoders and 30:1 reduction gearboxes. This combination gives a resolution of around 24 ticks per arc second when reading 4x via the encoder IC.This is plenty for provide tracking GOTO and tracking accuracy. During sidereal tracking, the arduino monitors the tick rates from the encoders and adjusts the PWM signal to the L298 to keep the telescope tracking the sky at the correct speed.
When tracking the sky, the motors turn at 12rpm. The Arduino programming language Reference, organized into Functions, Variable and Constant, and Structure keywords. Arduino then uses the known longitude of the observatory to. The DIY Arduino Telescope GOTO control project Why make your own Arduino control system? This combination gives a resolution of around 24 ticks per arc second when reading 4x via the encoder IC.
Knowledge of the target RA is then used to find the required Hour angle. You can follow any responses to this entry through the RSS 2.0 feed. I decided to make my own telescope control system from the ground up and the Arduino platform seemed the obvious choice. Astrophotography can be challenging, in a large part because your subject matter — or your base, the Earth rather — is constantly moving. Especially when microstepping. In order to take excellent long exposures of far-off objects, Redditor intercipere came up with a beautiful 3D-printable, star-following mount that holds and rotates a DSLR camera. For example, the overloaded interrupt lines will corrupt the serial data.
This just adds more questions of “how do you do it?” which is a serious customer feedback problem in our community for those interested in learning more. All such applications talk to telescopes using the common ASCOM interface. This system was extremely slow, underpowered and unreliable.
After completing my homemade telescope mount it was powered by a Meade DS motor kit. However, I do give isntructions on how to write it yourself here in my guide for writing Arduino telescope controllers, in my guide for writing Arduino telescope controllers. After completing my homemade telescope mount it was powered by a Meade DS motor kit. Fortunately ASCOM Drivers are well templated and easy to write.