On Mon, Jun 24, 2019 at 11:33 PM John Dammeyer <[email protected]> wrote:
> > I have some CAN bus experience if you have any questions. > John Dammeyer > One thing I don't know is if one transceiver chip works better than another. I can read the spec sheets but have no practical experience. I planned to use the MCP2551 in combination with the STM32 microcontroler's built-in CAN controller. But the TJA1050 seems like it will work too. There are many low-cost MCP2515/MCP2551 breakout boars on eBay. I plan to use them to prototype but then design a custom PCB for both Raspberry Pi and STM32. This is a motion control system not unlike LinuxEMC. Our design uses a Pi3 (now Pi4) as the central motion planner then we have some number, perhaps as many as 20 STM32 connected by CAN Bus and then these connect to the motors. We will use a mix of steppers, BLDC and PWM controlled DC motors About 24 axis in all. So We want to run CAN to distribute the data. This is for a humanoid robot. The first version models a a person in a wheelchair. The hands will be able to do anything a person seated at a table could do. We are using a pair of prothetic hands that are more commonly used for amputees but in this case they are attached to robot arms. There are ten motors in the hand alone, one for each finger Here is the overall application. It is an X-prize contest. https://avatar.xprize.org/prizes/avatar We do two levels of prototype. The first with cheap and simple stepper motors. Then later with more powerful BLDC motors running miniaturized variable speed transmissions. A human shoulder has three degrees of freedom and needs three motors, six for two shoulders. The challenge is to fit 6 motors and all those bearing in such a small space. But the simple prototype comes first. I just finished the the basic mechanical design and you can see it here https://a360.co/2N2ynIB The hand sed for prototype is here https://openbionicslabs.com The arm that conects shoulder to hand comes next. About 4 years of work remain for the team If this looks like an interesting project let me know, there is room for more. How is this related to LinuxCNC? Obviously there are many parts to be made. -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
