ECE 492 Senior Design Spring 2004

Cooperative Mining Robots Project




This page contains links to our project's monthly, quarterly, and annual status reports. Links to each month's report are generally made available during the first week of the following month.

For information about scheduled events and project milestones, see our Schedule page.

Status Reports

This Week


Some exciting news on the platform front!

Notice that our hardware is becoming more reliable -

consequently more predictable as we go along! At this point

we can trust the H-BRIDGE, SENSOR, POWER, & MOTOR CONTROL boards

and most of their firmware.

It's time to start integrating the COMM network with the platform!

We may want to get 2 or more nodes in the corridor [Monday after getting

sensor array boards] and integrate the Axiom and the 'bot COMM node.

We would not have to integrate MOTOR CONTROL/ NAV for this test.

We could track the bot [from the SUPV console] as it moves node-to-node.

Can we get ready for this on Monday?


WIRED/WIRELESS/SUPV - We met this morning and hit some of the

problem areas on the network. The nodes can now handle incomplete

messages. Shaun - send out the plan for the switch register. The

nodes are becoming generic COMM!

The shop completed milling and tinning of the final 8 COMM boards. They will

be drilled on Monday. The artwork for the sensors is now on Andy's machine

and he will produce 16 of them on Monday morning. Let's plan on retrofitting

the existing COMM boards with the sensor array and get the config book up

to date. I placed the 3 COMM boards that various people have been working

on this week in 400.

We should be getting the hardware early next week to begin installing the


in the ECE corridor. Let's try to have the code stable so that we don't

have to

reprogram 15 nodes while standing on chairs!

MOTOR - 'Bot #1 passed the field sobriety test! As Jason indicated in his

message, the 'bot was extremely stable in following the hockey tape

for about 15 feet. The MOTOR controller was executing the straight command

as it would be received from NAV and the production versions of the SENSORS

performed flawlessly. We should be in good shape for integration

with the Axiom board.

Jeff submitted the artwork for the wheel encoders to the shop and I will handle

getting the tape for on the encoder.

PLATFORM - Andy needs about an hour to finish the bump sensor brackets. I

will probably

get the stuff from him on Tuesday. I will also complete the #2 platform by

the middle of

next week.




Rob - I will take a look at the right drive train on Monday afternoon.

Last Week


4 COMM boards were delivered on Thursday [04/22] with the new

higher intensity LED. Given that we have not heard any status

as mandated by the meeting on Wednesday [04/21] we must assume

that this solved our coverage problems. I have scheduled a demo

for this afternoon [Monday 04/26] at 5:00.


The INTERFACE boards will be stuffed with the remaining ports

and SANITY logic this evening and will be available for integration

on Tuesday [04/27] before lab.


I picked up 300 feet of black electrical tape and an equal amount

of dull green cloth tape. The cloth tape will need to be split down

to a proper width if it works for our track. As of Saturday we were

able to run both drives from a function generator using the 'bot

power source.


We need to get an idea of any remaining parts required for the second

bot and spares. We have 7 COMM boards on order from the shop and I

have 3 in my office. These will be stuffed this week. We also need

to address the encoder boards. I will probably also do the BUMP sensor

for bot 1 tomorrow [Tuesday] night.


Last Month

Fellow Designees,

Hey everyone.... I just wanted to let everyone know what is going

on.... There was a problem with the transmission on the boards... This

problem stemmed from the line drivers... After meeting with Gum today we

decided to use the exiting verified code from the protoboard tonight to

check everything out.... I also had another thought to why it wasn't

working... the code Joe and Andrew had implemented to test the boards did

not incorporate the transmit ready signal... this signal is used to make the

line driver active to transmit without this signal being set for one node

at a time all of the node would monopolize the line causing errors in

transmission... also without enabling this signal with one chip would not

allow for transmission... Joe and prof. Gum also brought up the receive

signal which we will also check...




We had the inquisition and a plan is in place. Follow up with

a report.

I modified 2 Axiom boards and replaced the MAX232 with a socket.

Unfortunately, the chips did not survive the process. We have a 232 on

a protoboard in the lab. See if we can scrounge another until we

get more in. The boards are on the shelf next to the power supply boards

in our project room.

I modified the SUPV board with 820 pullups/downs as was decided in the

inquisition. There is also a 120 across A/B.

H-bridge. Get the boards and heat sink back to Andy tomorrow morning. Also,

check the artwork for the hole sizes that caused the bit to break the last




Perfectly milled PC boards!!!

Andy resolved the milling machine problems and we received 4 COMM

boards devoid of milling flaws. This will resolve MOST of our problems.

Parts storage looks good! I will be going through the parts and putting

out a MOUSER and DIGIKEY order[s] this afternoon.




I watched the email flying by on Thursday/Friday and have not responded

given some current performance with the email server. It was averaging

about 10 minutes to download one of the emails and I wasn't even going

to attemp a send.

1. COMM Boards - Good going on V4.0 artwork. Let's get into what

is going with the IR receive before the meeting. Also, has anybody

tried the ethernet connections between the PC versions of the boards?

We need to get to the bottom of the pull-up and termination issues for the

boards before the Monday meeting and get the documentation updated.

I will put in some effort on Monday night and try to get 3 more COMM V4.0

boards up and running. I am proposing [1] ceiling node configuration [SN0003

is currently ceiling] [1] bot configuration and [1] supervisor configuration.

Let's set the 2 ceiling nodes up in 400 for testing/integration.

2. H-BRIDGE - Good finds on the problems. Let's strap the FETs and integrate

with the motors as well as a bench config for controller integration. We

probably will not get the boards through the shop until Tuesday.

2A. SENSOR - Board appears about ready to go. Can we begin testing on


3. OS - Brooks - good going. We need to have a briefing for NAV and CENTRAL

for how their stuff needs to interact. [global variables, timers, etc.].

4. POWER - Boards look good at this point. Have we fired [maybe wrong

choice of words] them up?

5. SUPV/CCTRL/NAV - From what I have gathered, message formats are in

place. Given that the OS is stable, could we begin integration this week?

WIRED/WIRELESS can you support them?

6. GUM - As indicated above, I will stuff 3 more COMM boards and then

go back to focusing on the physical platform. I will also begin hanging

out with OS/SUPV/CCTRL/NAV this week.

7. DOC - We should begin the document for the end of the semester. Let's

take about half of the Wednesday session to lay out the final document

and determine what shape our current project binders are in.

8. PARTS - We need to get a handle on our parts. I am insisting that we

take time on MONDAY to organize our parts in the drawers. We also need

to determine what parts are defective and trash them.



Motor control along with central control determined the scheme for implementing the bump sensor(s).  Currently there are 8 positions on the robot for bump sensor switches.  We determined that we only need six [6], three [3] forward and three [3] aft in order to sufficiently implement a safety shutdown of the motors.  The switches shall be combined into one [1] signal and fed to a latch.  In the event the bump sensor is activated an alarm signal shall be asserted and latched until which time someone must manually reset the the alarm on the robot.  This alarm shall disable the power to the motors and issue an alarm to central control and ultimately to the supervisory station. When the alarm is reset at the robot the alarm shall be cleared throughout the system.  This was done because in the event the robot was in mid turn and it encountered an obstruction it was possible for the robot to loose its tracking capability on the tape leaving the robot stranded.  Therefore, the only way out of this situation is human intervention.
Motor Control got the H-Bridge working and was able to characterize the noise that the motor caused on the 12V bus
new parts ordering process
Encountered a mix up with a FET part number that cost us 1 lab period

Lafayette College complies with all applicable federal and state legislation and does not discriminate in any way on the basis of gender, age, race, color, religion, creed, national origin, ancestry, physical ability, or sexual orientation.
Copyright 2001-03, Lafayette College, Easton, PA
For problems or questions regarding this web contact [ProjectEmail].
Last updated: May 02, 2004.