KvM

Here another update. I added an opening rear door and changed most of the panels to white. Still enough work to do.

As you can see in the picture of the bottom, I use a series of gears to make sure the end rotation is always the same. This can be realized by a gear which is not fixed in position, but depending on the direction of motion, it is forced towards another gear. The little cylinder in the rear bottom switches the valves which allows to continue operate the main cylinder extending and then retracting. However due to the mechanism which fix the direction of rotation the motion of the tank is not continuously. I will show it later in a movie!

Here a short update. I started with the bodyworks. The drawback of light blue gray lego is the lack of curved panels. I doubt whether I will make the body more colorfull or just black? Any suggestion? I will continue to improve the bodywork before I implement the pneumatic compressor and the hoses. I will probably change the barrel and add plates to cover part of the tracks. Finally I need to add some details. A belly shot. I need to change the suspension system, which will most probably be a torsion rod based suspension system.

I had to slow it down to generate enough torque but from the first test it worked OK. At the moment I'm busy with the bodywork, which is quite challenging for me. Do you have any suggestions for more functions?

Yeah I know, my mistake. I see it is already changed! Pictures are just posted, i was struggling to deeplink them. Your response was too fast for me

Can my title be changed as well Instead of [TC], it should start with [TC10] Here is the link http://www.eurobricks.com/forum/index.php?showtopic=140428

I'd like to show you my progress on my pneumatic tank. It includes the following functions: Driving Rotating of turret Shooting Barrel adjustment Both tracks can be controlled separately. I used gearracks to transform the linear motion into rotation to drive the tracks. I used a combination of gears to allow the tracks to move forward by extending and contraction of the cylinders. Therefore it is ony possible to drive forward. I limited the rotation of the turret by a 90 degrees to the left and 90 degrees to the right. This allows for the hoses to go through the turntable. The shooting mechanism shoot when the cylinders extend, and when the retract. This allows for relatively fast shooting. Do you have any suggestions what can be added or improved, just let me know.

Well yeah thats basically it. Although I made a version which contains only 1 switch. A pneumatic engine (LPE) is allowed to be used when operated by a hand pump?

OK, if someone is interested, I can build a test setup to make the idea clear and allow you to test the vacuum system yourself. For the contest I will find something else.

Can I get a final answer on whether it is allowed to create a vacuum by driving a normal cylinder? Otherwise I have to come up with something else.

no its still a bit different. I tested this idea before. The motor revolves a cylinder and at the same time a valve is switched. If you connect the tubes correctly and switch the valve when changing the direction of motion of the cylinder you can create a vacuum. See a device i made which is used to make pavements: http://www.brickshelf.com/cgi-bin/gallery.cgi?i=5731642 I was able to lift my Samsung s4 by using this technique. It just reverses the process of a pump.

I just meant the normal cylinders with two port. But instead of actuating them by a valve, I want to use them to generate a vacuum for a gripper. In order to do so I have to drive them by a motor, just as you would do with a pump, but this time a cylinder is extended and compressed by the pf motor. So in this case the cylinder is used as a pump, however it is generating the vacuum.

I mean the cylinder with two ports. Is it OK to drive those?

I was thinking of making a vacuum gripper by powering a pneumatic actuator. So apparently that is not allowed?! The gray bricks, which were used for the old cylinders with one port, are not strong enough for a good vacuum. So might this be an exception?