First Week of July
We have been having a few problems with the software. How unusual! While working on the mechanics of Arnold at the weekends, during the evenings in the week we have been developing the software for the interface between the standard hobby radio gear and the speed controllers. We can measure the duration of the Pulse Width Modulation(PWM) coming out the receiver okay, but we get inconsistent results, especially when decoding more than one PWM signal at the same time. Work continues on trying to resolve this.
Second week of July
We have made some progress on the software. I have always assumed that the individual PWM signals coming out the receiver would be following each other in time. Yes this is the case unless you are using the Pulse Coded Modulation(PCM), digital. With PCM, the receivers PWM channel one and two start at the same time. Dooh no wonder I have been having trouble decoding them. The code is now re-written to cope with this and the results are far better and so "Arnold, Arnold Terminegger" has been moving about under his own power.
The upper polycarbonate armour, has been constructed and fitted. We also did some work to the self righting system and fitted small side arms to to get him able to self right from his sides. We added some bars at the back of the lifter to enable him to self right from his rear.
We also fitted the lamps for the eyes and promptly blew the lamps up. What's wrong here, ahh.. the lamps are only 12 volt, not good on a 24 volt system. A bit of rewiring, new lamps and the eyes are now working reliably.
Monday 17th Smoke signals indicated the demise of the H-Bridge for powering the Lifter/Self righter's Linear actuator.
Tuesday 18th Too tired to do anything.
Wednesday 19th Rebuilt the lifter drive circuits and promptly burnt out the linear actuators motor!
Thursday 20th Fitted Front Armour, polycarbonate, and ordered a new motor for the lifter.
Friday 21st Collected New Motor on way to work and fitted it in the evening on to the actuator. Very nice the motor is at least twice as powerful as compared to the previous motor.
Saturday 22nd Finished fitting the armour on to Arnold and did some robust testing of the self righter. Blew up the electronics again and broke the fitting which connects the linear actuator onto the lifting arm. A simple bolt repairs the arms connection, and yet another replacement FET and relay in the drive circuit.
Sunday 23rd Fitted winch and lifter onto Miss Struts, looking good. We also took Arnold to a local car park to do some testing. Had some fun for a couple of minutes and then lost drive on one wheel. We return home to find the pinion is turning on the spindle of the motor. A bit of locktite and tightening of the grub screws and now seems okay.
Monday 24th Robot Mayhem (The Trials) start at Park Street Studios, not for us until next weekend..... luckily.
Thursday 27th Started making up electronics for driving the winch on Miss Struts.
Friday 28th Completed the drive electronics, and with a bit of reprogramming Miss Struts control software, the winch is working. Hey now that is nice, will lift me easily, no strain on the winch. Umm but we did have to reinforce some of Miss Struts chassis to stop it being crushed!
Saturday 29th We fitted some more polycarbonate armour to the top of Miss Struts, to improve the protection around the backward and forward rams' sensors. We also took Arnold to the car park again, umm... he is not easy to drive, and again, after about five minutes of fun we lost drive to a wheel. Turned out to be exactly the same problem as before but on the other wheel. The rest of the day was then spent loading up the robots in to the trailer for tomorrows trials.