i have a project in mind involving my tractor and my farming operation. what i want to do is use gps to steer the tractor for me (that i will be riding in at all times!) so i can focus on other tasks while doing tillage and planting. it will only have to drive in a straight line i will make the turns and line up for the next pass. my thoughts were have a pixhawk and piksi along with a stepper motor assm to manually turn the steering wheel. two methods i was thinking of were trimble ez steer or agleader. we have used a light bar guidance on our farm before but this year going to conservation tillage and need to drive over the previously placed fertilizer strip with the planter within 4" or better. with our small farm we can not justify the large expense of RTK.
what is everyone response or concerns to this idea? i appreciate any input or suggestion i can overlook some important details at times
thanks
Replies
i was assuming the pixhawk is the best option for a project like this. is there any anticipated changes or up date in the near future that i would be worth wait for?
Robobill did you order or plan to order a piksi as well?
thanks for the input!
YES! absolutely... I do plan to buy a Piksi system ASAP... I've read they are expecting to ship in April. In the meantime I'm playing around with the Pixhawk/3DR GPS to get familiar with all the settings/parameters. IMO, the documentation for these UAV systems is difficult to navigate (sorry). Hopefully I will be up to speed in a month... ready for the Piksi.
Andy,
John Deere make this sort of system already. You will probably be able to source the parts cheaper than one of their (or other) bolt-on systems, but it will take time. You'd need to weigh up the value of your time.
I don't know how farm equipment insurance works, but if something goes wrong and you've modified the gear, or something happens while it's under autonomous control, you may be in trouble.
A "stepper motor to control the wheel" is not necessarily as easy as it sounds - you need a mechanical linkage, a feedback system, and a controller. One baseline is the gear from Dimension Engineering, and you're looking at about $150 for their Kangaroo / Sabertooth combo.
You may not need a Piksi if you have decent GPS coverage and can survive with metre resolution.
One of the problems with the steering system will be the ease with which you can disengage it to steer manually. You'd need a motor that can be backdriven.
TCIII for Michael Roberts
I also am looking forward to hooking up a Piksi system to my rover. I do need control to within 2 or 3 inches. The cost of Piksi is still a little steep but its much cheaper than existing tech.
As for steering the tractor, my suggestion is to look back at an old Mythbusters episode where they proved that the bus in the movie Speed could survive the hard right hand turn. The bus was controlled remotely, but how/where did they attach the actuator... was it to the steering wheel or ...???