Jim Just to add to my last you might want to look at Analog's ADXL202 or ADXL05/50 Mike ----- Original Message ----- From: "Jim" To: Sent: Wednesday, July 10, 2002 4:00 PM Subject: Re: [PIC]:how to use acceleration sensor for motion control? > Hello > I'm building a small robot and was planning to build a tilt sensor that > should measure acceleration to. > I only have the idea I haven't done any testing yet. The idea is to make a > small pendulum with a ferrite > bead as the weight. Near this will be a coil that is part of a tank circuit > of an oscillator as the ferrite bead > swings near or farther from the coil the frequency will change and I will > keep track of it with one of the timer > inputs on a PIC. The pendulum may need to be dampend. I once saw a small > scale that had it's beam > dampend by having a small copper plate attached to the beam swing near 2 > small magnets this would > cause eddy currents in the copper and dampen the beam movment. > > Regards > Jim > > > -----Original Message----- > From: Pang accelerationacceleration > To: PICLIST@MITVMA.MIT.EDU > Date: Wednesday, July 10, 2002 12:47 AM > Subject: Re: [PIC]:how to use acceleration sensor for motion control? > > > >Hi, > > > >I have posted some questions on the area of acceleration sensor some months > >ago and gain a lot of knowledge from other piclisters. For searching > >purpose, the subject of the thread is [EE]:Tilt Sensor. A two axis > >accelerometer are basically used to detect both dynamic acceleration > >(vibration) and static acceleration (gravity). As such, a dual axis > >acceleration can be use to detect vibration, tilting, and acceleration. > > > >I have given up on searching for a tilt sensor solution because > accelerators > >are very expensive. ADXL202 is expensive and fragile. You can check also > the > >accelerators from Memsic, but they are also very expensive (USD14.50). > > > >As for the rotational sensor, piclisters has suggested on using a optical > >encoder or ball bearing potentionmeter or electrolytic tilt sensor. Have > yet > >to get some samples on that. Perhaps you can consider these for rotational > >sensor. > > > >There could be others which I do not know. > > > >Rgds, > >Pang > > > > > > > >Subject: [PIC]:how to use acceleration sensor for motion control? > > > > > >need to control two dimension movement, speed and distance. or may be even > >rotation movement. > > > >how good sensor is needed? 0.01 mg , from analog device, enough? > > > >acceleration sensor should works, theorically. any example? site? > > > >BR, > > > >-- > >http://www.piclist.com#nomail Going offline? Don't AutoReply us! > >email listserv@mitvma.mit.edu with SET PICList DIGEST in the body > > > >-- > >http://www.piclist.com hint: To leave the PICList > >mailto:piclist-unsubscribe-request@mitvma.mit.edu > > > > > > > > -- > http://www.piclist.com hint: To leave the PICList > mailto:piclist-unsubscribe-request@mitvma.mit.edu > > -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads