Cerebellum Project Progress Reports

Cerebellum Project Progress Reports

Progress Summary

6/04/01: Plans, Stuff Done
6/11/01: Plans, Stuff Done
6/18/01: Plans, Stuff Done
6/25/01: Plans, Stuff Done
7/02/01: Plans, Stuff Done
7/09/01: Plans, Stuff Done
7/16/01: Plans, Stuff Done
7/23/01: Plans, Stuff Done
7/30/01: Plans, Stuff Done
8/05/01: Plans, Stuff Done
8/13/01: On vacation
8/20/01: Plans, Stuff Done

Get PalmPilot Robot Kit hooked up to cerebellum PCB, and run the simple obstacle avoidance function on it. Test output ceiling by driving 8 servos on the servo interrupt routine.

Stuff done for week of 6/11/01

I got the PPRK running around using the wandering algorithm that you described to me on Monday. I also played around with the DC motor and steering servo on Robocat.
I asked for samples of the I2C PWM chip from Dallas Semiconductors, but from experience, they won't arrive for another week or so. I tried looking around for them online, but no one seemed to have them in stock.
I've connected a HP encoder counter up to the PIC, and I'm getting encoder readings from a Pittman motor that Chuck bought.

Plans for week of 6/18/01

For the week ahead, I am planning to work on some I2C code, in preparation for the arrival of the PWM chip. I would also like to order a few more of the Sharp position sensors (unless there are more available somewhere else...). There's a list of stuff that I'd like to order, including encoder counters, position sensors and protoboard pin-headers.

I would like to put 3 of the Sharp sensors on Robocat, and use those to implement obstacle avoidance. I could take the sensors from the PPRK, but I'd rather demo the PPRK first before taking off the sensors.

With the feedback from the encoder counter chips, I can also try to do some PD/PID control using the PIC.

Stuff Done for week of 6/18/01

A list of parts have been ordered for project's upcoming requirements. It has been decided that we will go forward with the daughter board DC motor controller architecture. Code for the PID velocity controller has been started, but it's not working properly yet, more debugging is required.

Plans for week of 6/25/01

This week, I will be spending most of my time working on the PID control loop. When the Sharp PSD sensors that were ordered arrive, I will rig them onto Robocat, and we should have another demo available within the subsequent 2 days. Some time will also be spent moving down into your lab in the A-level. This will probably be on Friday.

Stuff done for week of 6/25/01

Since we last spoke on Wednesday, I've gotten the velocity controller fully tested and running as a 300Hz interrupt routine. Chuck and I also spent some time moving all our equipment from the REL into your lab at the A-level. Prof Mason has informed me that he does not have any equipment to spare. Someone in the Roboclub did build a diffdrive robot before, and for some time it was sitting around without a controller, but I went to look for it on Friday and discovered it dismantled.

Plans for week of 7/02/01

I've received all of the stuff that was ordered from the various suppliers last week. So now, I can spend some time rigging sensors onto Robocat and work towards demo'ing it. I can also spend time putting together a chassis that can be used to demonstrate velocity control.

Stuff done for week of 7/02/01

There are now 3 possible ways of getting encoder readings. We can use the HP encoder counters (the most straight forward method, also the most expensive in terms of dollars and resources). We can use the US Digital chip that converts quadrature counts into a clock and a direction signal. This uses an 8-pin US Digital IC and 1 timer on the PIC. Lastly, we can wire up a dual flip flop IC to convert the quadrature signals into an up count and a down count signal. This uses 2 timers on the PIC for counting, and a standard 7474 IC.

Plans for week of 7/09/01

Work on interfacing with Anthony's camera to produce the Elmo Tracker. Finish up the 2nd revision of the cerebellum's PCB design, and send it for fabrication.

Stuff done for week of 7/09/01

Elmo Tracker has been completed. Video is online, in the Vision section. Cerebellum PCB revision 2 has been sent to Alberta Printed Circuits, should arrive on Tuesday. One motor driver daughter board has been laid out on a protoboard. Initial design of the duaghter board PCB has been done. This design will be edited according to the performance of the protoboard circuits before being sent for fabrication.

Plans for week of 7/16/01

Main objective is to have the diff drive platform moving around by Friday. Layout another daughter board, perhaps start by having one enslaved to the other and drive around. Connection will be over serial link initially, later progressing to I2C. Work on I2C code for the PIC should start by mid-week.

Stuff done for week of 7/16/01

I2C master and slave mode software utilizing the Master Synchronous Serial Port hardware on the PIC16F87x has been written and tested. Another version of the I2C software that does not require hardware assistance has been written, but not tested.
Ordered parts have arrived, so we now have enough "raw materials" to stuff more Rev2 cerebellum boards.
An error has been found on the schematic of the fabbed PCB. There is one missing connection from pin 40 of the PIC to pin 6 of the programming connector (JP4).
Once the diff drive base is finished, getting it up and running with 2 daughterboards (on a protoboard) and 1 cerebelllum (PCB) shouldn't be too difficult.

Plans for week of 7/23/01

Design the daughterboard PCB, and send for fabrication.

Test software (bit-banging) I2C routine. If this works, we can use a smaller pin-count PIC on the daughterboard and reduce the PCB's size.

Draft the serial interface specifications for the cerebellum board.

Stuff done for week of 7/16/01

Software I2C testing failed. PIC (at 5MIPS) cannot catch up with the 400kHz clock signal used by I2C. I2C without hardware assistance is probably not worth the effort.
Daughterboard PCB design has been sent for fabrication, should arrive on Monday.
Cerebellum serial interface specifications now stands at version 0.2, and is ready for the first implementation.

Plans for week of 7/30/01

Daughterboard PCBs (and parts) have arrived, so it's time to stuff and test them.

Work on implementing v0.2 of the cerebellum's serial interface.

Release v0.1 of the daughterboards' I2C interface specifications.

Stuff done for week of 7/30/01

One daughterboard PCB has been stuffed and tested. All components are working.
Cerebellum serial interface implementation is ongoing. It stalled around mid-week due to compiler limitations. Has since restarted with the CCS compiler. Core components and daughterboard code has been ported and work has resumed on the cerebellum's serial interface.
Version 0.1 of the daughterboard interface specification is now online.

Plans for week of 8/05/01

Finish the first implementation of the cerebellum firmware.

Start on daughterboard firmware.

Assemble another daughterboard and try to run the diff drive base.

Stuff done for week of 8/05/01

Major features of the cerebellum firmware have been implemented.
Daughterboard firmware is done.
Testing has been done on the diff drive. Functionality is there, but the base cannot dead reckon solely on velocity control.
Software serial port on the PIC has a maximum speed of 9600 bps, and does not give error free transmission.

Plans for week of 8/20/01

Do one last revision of the cerebellum board and send for fabrication.

Find a solution to the software serial port issue.

Documentation.

Contact: kwanjee@andrew.cmu.edu -- First Edition: 06/12/01 -- Last Update: 07/22/01