PTHAT Controlling Parallel Scara Arm using Instant Commands

With this example, we show how to control a Parallel Scara Robot Arm with the PTHAT.

The Parallel Scara is one of our prototype machines and it set up with a 200mm x 200mm working area. 

Within the software you will see the pulses per revolution set to 80’000 pulses as we used 50:1 harmonic gearboxes and stepper drivers set to 1600 micro steps.



Within the application you first connect to your Raspberry Pi serial port by clicking the Connect button.

Make sure your Parallel Scara Arm is set to the home position and click on the Reset button.

Now set your target movement X and Y and click on the Calculate button. It will not plot where your arms are going to end up being and also do all the inverse kinematics calculations to get a final pulse and direction result for both motors.

Now finally click on the Send button and it will send out the commands to move the arms to the target setting.

Watching the video below will give a better overview.

Commands used in this example are:

Set Axis Command

Start Axis Command

Request Current Pulse Count Command


In this video we give an overview of the example software we supply to control a Parallel Scara Robot Arm.

The end developer has easily modify this example to build their own application.

The example application was developed in Visual Studio 2015 that can be used with Windows 10 IOT on the Raspberry Pi or compiled to x86/x64 for use on a PC.
The example has been written in C# as a Universal Windows Platform (UWP).

Please use the following link to download the full source code.

Closer look at the PCB's