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About LinkBacksIt does work that way, so it should work fine. ThanksOriginally Posted by mcm_xyz
It does work that way, so it should work fine. Thanks
MCM_XYZ,
Thanks for posting the pictures. The motor mount of the mouse parts is pretty clear. How simple!!
RipperSoftware
Hi Mike,
Thanks for posting the pics, and the information on your drives and servo's. I'm still coming to terms with the simplicity.
You mentioned some minor software changes, what did you end up changing?
I'd be happy to share my board design too for those interested, but it will be a while before I have anything worthy. As in my first post, mine is based on IRF540 fets actually mounted below a CPU heatsink and fan assembly.
I've attached a preview of my board.
Pat
Hi Pat
Keep on working... I have changed only 2 values in the original program provided by Chan.
INI_MODE changed from 2 to 3. To start the servo in positional mode directly.
SYSCLK from 18Mhz to 15Mhz in concordance with the frequency of the Xtal I used in the schematics. If this second value is not changed the serial commnunication will not work.
Thats all...
Although I am a software engineer, assembler is beyond my power of understanding. So I can not say I am getting very much out of that code although it is nicely quoted...
Mike
I'm almost finished with the boards design. I'll post them next week (hope so). However the boards are based on a different schematic that has some amplifiers / trigers for my custom servos and a different H bridge driver and H bridge.
The board and schematic are designed with express PCB and will be very simple for someone to change as desired.
Mike
Hi Mike,
Thank you in advance for your work. Can you post detailed information about your custom servos too if it is not to much trouble. Will it also work with standard off-the-shelf servos or has it been to customized?
Thank you
Steven
Hi Mike,
have you finished your boards. Do you have some more informations about your servos?
greetings from germany
ralf
Hi Mike
have you finished your boards. Do you have some more informations about your servos?
greetings from egypt
hesham
sorry for the late answer
I have been very busy doing some other stuff lately so the boards are not ready yet. I am going to try not to let u folks down.
About the custom servos... Some advices...
1. Buy a cheap DC motor...
2. Look for and old brokem mouse in the house...
3. Measure the diameter of the stick of one mouse wheel...
4. Drill a hole on the back shaft of the motor as straight and centered as possible... It will help a lot if you remove the rotor from the motor...
5. Put the wheel from the mouse in the hole and glue it.
So much about the mechanics...
A little about electronics. It will be of great help if you will use single capsule double phototransistors. There are old mouses that had 2 separate phototransistors for obtaining a quadrature signal. It will be very hard for you
to find the right position for two separate transistors. Use single capsules.
I have used A4Tech mouses and they all have a single transistor.
The IR LED must be powered from 5V using a 1K resistor in series or it will be destroyed.
Best to you all
Hmm.
The modified board should work with of the shelf servos as well. It is not important if you connect A and B or !A and !B of the servo...
Grretings from Romania
Mike
Hi Mike
have you finished your boards I have 4 hitaci dc motrs 19 w 24 v + encoder 100 ppr
Hi Pat
I have been trying to design a H bridge for a while learning all the time, it is actually for a welder but the same principles apply I guess. I was just wondering do the fets north of the bridge have to be p channel fets and the fets to the south 'n' channel fets reapectively?? I see you have specced IRF 540s on both the north and south. Will this work will they stturate fully etc. I don't know enough about all this at the moment but I keep seing both types of designs, could you shed any light on the benefits of all 'n' channel and a mixture of 'n' and 'p' channel??
Many thanks for your time
Dom
