Making a ball loader for grandsons pitching machine in their batting cage

I hope that I might get some input as to how to index one ball to release. I made an eight foot troff that holds 15 3" balls at my stop. I mounted one end a 6" strap hinge to plywood. The other end just flops. I installed an eye hook at the end of hinge. Drilled 1/2" hole through plywood for end of eye hook. The eye hook protrudes approx 1/4" below plywood to stop balls. To actuate, I mounted 12" shelf bracket to plywood and at the top I put a pulley. I have a 1/8" rope which attaches to eye hook, through pulley, the extends approx 30’. To release one ball grandson pulls rope which lifts hinge allowing ball to move. The first time of use all 15 balls came flying out at me. The hinge totally flopped over. Next try I put additional weight on hinge using some heavy washers on shaft of eye hook and restricted hinge upward movement to 1/8" . Now I can pull pretty hard on rope but if you hold rope to long more balls sometimes go through. I am looking for some inexpensive way to make only one ball being released and ideally eliminating pull cord to actuate to some wireless control so all grandsons have to do is press remote to get ball to release. Present incline allows the balls to roll to machine in about 4 seconds.
Thank You for any input you might have and where to get parts. The pitching machine has 110 volts Ac on a ground fault outlet.
Regards ,


Are you planning to do this with VEX parts? If not, I’d try asking this on


I do not know what parts would be needed and will wait for some response and also post to


McMaster-Carr is an amazing place to buy parts for projects of all kinds. I highly recommend checking them out if you’re looking for stuff

If you want more detailed feedback from us sending pictures would help a ton

side note- while this forum is not the ideal place to ask for help on a project like this, due to the fact that the large majority of us here are high schoolers and have minimal exposure to the field of engineering outside of vex, most of us would be happy to help, : )


Hi Ethan,
Thank you for response. I have been on Mcmaster Carrs website and have used them for other stuff. My problem is not knowing what is actually needed to index one ball at a time, remotely. I did not know what Vex was when I signed up. It came up using a google search. I think I will tell my oldest grandson about vex. Some of these high schoolers are more knowledgeable about indexing than I am. Somebody will give me some answers or suggestions.


Hi @ScottN,

I presume you are looking at the possibility of using vex parts to do your pitching machine (since this is a vex forum).

From my understanding, most pitching machines used a double flywheel to launch the ball.

Here’s a video of a double flywheel.

It is not by my team, but they are the team that popularised double flywheel in vex.

Hope this is what you are looking for.


Probably the simplest method for wireless control would be to buy a very cheap rc car($20 or so) and replace the replace one of the motors with a small geared DC motor to actuate the hinge. To control it you would simply move the joystick for just long enough to release one ball.
If you were alright without wireless control you could go even simpler and connect a motor to a battery pack with a long wire leading to a button.
This kind of motor would probably do:
Note that you won’t be able to use a servo with this method as it requires a special signal.

If you want to use Vex electronics, the current generation of Vex parts(V5) are very expensive and you will be looking at $1000USD for the starter kit, probably way too much for this project.

I would recommend reaching out to any vex teams/robotics clubs in your area to see if they have any old sets and motors which are no longer competitive in competition, so you’ll probably be able to get them cheap. Try asking on the forum if anyone has old cortex kits in your area.

A much more difficult option for wireless control would be to use an ESP32 microcontroller. Various modules can be bought very cheaply for ~$5-10 which have onboard wifi and bluetooth so you can communicate between modules, or to other devices. This option is much less plug and play however and would require some time invested to get it learn how to get it working and learn how to program wireless control.

If you are using a microcontroller(Vex V5/Vex Cortex/ESP32 etc) you could program a motor/servo to lift up the hinge for a specified time to release one ball, or you could use a light sensor to detect when one ball has been released so that the hinge can be dropped.
The Vex options are very much plug and play and programming would only be a matter of binding the motor to the controller.
The ESP32 or some other non-vex microcontroller would require a much greater depth of programming knowledge and you would have to set up the wireless link between modules yourself. It would also require some electronics knowledge to wire it up correctly. A servo would be ideal to move the hinge as it would mean that you wouldn’t need a separate motor controller to control it.

A much easier alternative to an esp32 for beginners would be to use an Arduino Uno and just control it using a long wire with a button on the end. The Uno is simpler to setup for programming and the board is set out to make wiring a lot simpler for beginners.
Power for the ESP32/Arduino Uno could be provided by a 6-12V DC battery/power adapter(the closer to 6V the better).
Numerous tutorials are available online and on YouTube for these options and I’m more than happy to help if you need any clarifications.

TLDR since I’ve rambled on for far too long:

  • Vex V5 electronics are probably way too expensive for this.
  • My top recommendation would be to reach out to Vex robotics teams in your area to see if they have any old Vex cortex kits which you’ll probably be able to buy for cheap.
  • An ESP32 or Arduino microcontroller and a servo would also be an option if you’re willing to put the time into learning to program and wire up them.
  • The quick and dirty approach would be to wire up a motor to a battery and a long wire with a button on the end to control it.
  • You could also buy a cheap RC car and replace one of it’s motors with a geared motor to actuate the hinge. This would allow you to control it with the joystick.

It may also be easier to set up the system similar to many commercial batting cages. You’d press the button once to start, which would start the program, and then it would launch all the balls with a certain time gap in between. This way the button wouldn’t have to be pressed so many times and the batting cage could be operated by only one kid. It is worth noting however, that you would also want an estop with this configuration so the sequence can be stopped in the event something goes wrong.

Hello everyone ,
My head is swimming with responses. Thank you all ! Servo, microprocessor are so far out of my realm. The pitching machine being used is a single wheel flywheel. My problem is in just releasing one ball at a time loaded in the troff to allow one ball to roll into the pitching machine by gravity. My thought was to maybe use just a retractable solenoid and get rid of my crude hinge, eyehook, pulley and rope. Using a wired momentary switch or some sort of wireless to activate solenoid to release a ball. Thoughts?

1 Like

You can use a rotating trapdoor like that in a ball machine.
Screenshot_20200904-234003_Samsung Internet

Figure out how far you have to pull the rope to make a quarter turn and that will allow you to drop balls in one at a time


If you are looking at single flywheel, then you can’t go too wrong with this thread:

You will need to do some adaptations with the “intake” to some sort of a tray to hold the balls?


Great ball contraptions often face this problem of “ball serialization”; you might be able to draw some inspiration from looking at GBC modules.


If you’re using any sort of contraption similar to Nothing But Net or Turning Point, then you’d probably need one last conveyor, indexer, before your flywheel. When coded right it’ll index one ball at a time. You can also automate it so when you push a button it’ll index one ball into your flywheel, and another ball will be loaded into your indexer.

Here’s an example of one (skip to 1:20), but it doesn’t have to be so complex. Hope this helps!

Hi Guys and Gals,
Yesterday I found a door bell with a solenoid. The plunger has a spring which is always extended at rest. 12 volt power to it causes it to retract. With some adjustment as to protrusion of plunger to hold balls, it worked good. I used a old 110 v to 12 volt dc power supply from an old computer and ran 30’ of wire to a momentary switch and back to the solenoid . No servos, boards or programming.
You robotic people are just fantastic but way over my capabilities. Keep inventing. I just loved to watch what you guys and gals do for your projects.
Thank you all for your input.


glad to hear you found a solution. have fun!


Does that mean us robotics kids over-complicated something? That’s impossible, we never do that!



Austin, you are pretty funny. It seems like keep it simple is hard to do when you want all the bells and whistles on your robots. Every robot I viewed was amazing to me and complicated in my mind. How did they do that?


Haha, thanks!

We have a motor limit for competitions, which forces us to do some pretty cool things in order to maintain efficiency. Trying to do everything with limited resources is really difficult, but gives us fairly realistic expectations for STEM jobs later. Although, I don’t understand half the things that go on here either xD

I wish you luck with your pitching machine! Your grandson seems pretty lucky!


This topic was automatically closed 365 days after the last reply. New replies are no longer allowed.