Mechatronic Billiard Cue Stick - Robotic Support Helps You Win the Game

In many areas robots are better than us. They are more precise, great at computations and can work without interruption in continuous mode. Their advantages are used in many industry areas, but mechatronic projects can be also a bit crazy, but very interesting scientifically and technically. An example of such an application is billard cue stick.

Shane from Stuff Made Here decided to design and make a mechatronic billiard cue stick, which allows to support the player in hitting the ball. The gameplay boils down to two steps: figure out what shot you want to take and hit the ball. Of course in the background the mind makes calculation how to do it to achieve the goal and defines strength and direction of the hit. As we said, in many areas robots are better than us. But for now people are building robots and are 'teaching' them how to perform tasks.

First step is to get information what happens on a pool table. It can be done using camera system needed to watch the game. Next an algorithm interpret the balls setting and figure out the best shot. Having a complete set of information, the mechatronic system needs the tool like robotic stick to hit the ball. Sounds simple? Shane said:

This is probably the most complex project that I've done.

The pool is not 2D. Where you hit the ball vertically matters a lot. Off center hits put spin on the ball which gives you control over where it goes. The project assumptions were to allow to the player pre-set the cue stick and let the algorithm and mechanism set a taper of shaft correctly and hit the ball. So that, the robot have a control of moving and rotating vertically as well.

The idea is similar to Stewart platform (six telescoping rods in a very special arrangement) which allow completely control tip of a pull cue. But instead of the telescopic rods Shane use linkages on the cranks which push them up and pull them down. The platform is driven remotely through tension cables and servos. The movement is carried out by a programmed algorithm. To generate the hit power the air cylinder and pressurized air is used. The adjustment of the impact force is performed by pressure tank. The controller measures the pressure, and if it is to high it will open the valve to release the pressure.
Shane use the camera mounted on the ceiling looking straight down, tags on the table and stick and complex algorithms. It allows to get information what happens on a pool table. 

To show the player how to set the stick the projector was used. Not everything was obvious and simple and sometimes Shane ran into several problems while preparing software for his mechatronic billiard cue stick:

So this is roughly equivalent to punching myself in the face for five days straight.

Sounds familiar? But finally the balls go to the target with no random. Additionally, the system offers support in making the decisions of hit the balls order. The system built by him is impressive! Just have a look at the video below: