playerstage-users

 [Playerstage-users] Problem reading linear and angular speed (P3-DX) From: Marcelo Salazar - 2007-12-05 13:16:08 Attachments: text/plain image.png
 Re: [Playerstage-users] Problem reading linear and angular speed (P3-DX) From: Geoffrey Biggs - 2007-12-05 15:11:09 ```Neither hardware nor the real world are perfect. Don't expect a real robot to be capable of perfectly achieving what you ask, particularly with low values. Geoff Marcelo Salazar wrote: > Hello: > > > > I need to make a controller for the “P3-DX robot” but I don't understand > the behavior of the robot. > > > > I'm sending different goals of linear and angular speed, but the robot > give me a different data of speed. > > When I try the controller with Stage, it's works well. > > > > For example: V=[linear speed] ; O=[angular speed] > > > > I send I receive Obs. > > ----------------------------------------------------------------- > > V=0.1 V=0.1 That's right, no problem > > O=0.0 O=0.0 That's right, no problem > > ------------------------------------------------------------------ > > V=0.1 V=0.09 (aprox) This speed fall 10% aprox. > What's happen here? > > O=0.1 O=0.055 (aprox) This speed fall 50% aprox. > What's happen here? > > ------------------------------------------------------------------ > > V=0.0 V=0.0 (aprox) That's right, no problem > > O=0.1 O=0.0 (aprox) What's happen here? > > ------------------------------------------------------------------ > > > > I attach an image to explain the problem. > > Red: linear speed goal, > > Blue: linear speed read, > > Green: angular speed goal, > > Black: angular speed read. > > > > I don't understand what is the problem. > > Somebody know any problem with P3-DX and position2d? > > > > a greeting, > > Marcelo Salazar ```
 Re: [Playerstage-users] Problem reading linear and angular speed (P3-DX) From: Marcelo Salazar - 2007-12-05 15:21:15 Attachments: Message as HTML ``` Hello again: I'd like to add that I'm using Simulink and Real Time Workshop to generate the executable. I'm reading "inputs" and writing "outputs" each 100mS: static void mdlOutputs(SimStruct *S, int_T tid) { real_T vlineal,vangular; InputRealPtrsType uPtrs0 = ssGetInputPortRealSignalPtrs(S,0); InputRealPtrsType uPtrs1 = ssGetInputPortRealSignalPtrs(S,1); real_T *y0 = ssGetOutputPortRealSignal(S,0); real_T *y1 = ssGetOutputPortRealSignal(S,1); /* Write data to the server */ vlineal= double(*uPtrs0[0]); vangular= double(*uPtrs1[0]); playerc_position2d_set_cmd_vel(position2d, vlineal, 0, vangular, 1); /* Read data from the server */ playerc_client_read(client); *y0 =(position2d->vx);/* linear speed*/ *y1 =(position2d->va);/* angular speed */ } Perhaps somebody can understand where is the problem: I send goals of linear and angular speed; and the robot moves different" Thanks in advance. Marcelo Salazar Hello: I need to make a controller for the "P3-DX robot" but I don't understand the behavior of the robot. I'm sending different goals of linear and angular speed, but the robot give me a different data of speed. When I try the controller with Stage, it's works well. For example: V=[linear speed] ; O=[angular speed] I send I receive Obs. ----------------------------------------------------------------- V=0.1 V=0.1 That's right, no problem O=0.0 O=0.0 That's right, no problem ------------------------------------------------------------------ V=0.1 V=0.09 (aprox) This speed fall 10% aprox. What's happen here? O=0.1 O=0.055 (aprox) This speed fall 50% aprox. What's happen here? ------------------------------------------------------------------ V=0.0 V=0.0 (aprox) That's right, no problem O=0.1 O=0.0 (aprox) What's happen here? ------------------------------------------------------------------ I attach an image to explain the problem. Red: linear speed goal, Blue: linear speed read, Green: angular speed goal, Black: angular speed read. I don't understand what is the problem. Somebody know any problem with P3-DX and position2d? a greeting, Marcelo Salazar ```
 Re: [Playerstage-users] Problem reading linear and angular speed (P3-DX) From: Reed Hedges - 2007-12-05 16:18:48 ```Do you know if anyone has ever modified the firmware parameters? There are some "calibration" parameters, typically they don't need to be changed but you could try it if you want. Save a copy of the parameters before modifying the live ones. These parameters match an amount of encoder ticks to actual distance or rotation, see the Pioneer robot manual chapter 8. You can also just try the player examples or playerv or ARIA's demo to double check that it isn't something in software. But it can not match perfectly, as Geoffrey said -- especially in rotation. Actually, has anyone on this list ever done the Pioneer encoder calibration procedure described in the manual (chapter 8)? If it's something that people do more often than we think, we might make a tool that makes it easier to do. Reed Marcelo Salazar wrote: > Hello again: > > > > I’d like to add that I’m using Simulink and Real Time > Workshop to generate the executable. > > > > I’m reading "inputs" and writing "outputs" each 100mS: > > > > static void mdlOutputs(SimStruct *S, int_T tid) > > { > > real_T vlineal,vangular; > > > > InputRealPtrsType uPtrs0 = ssGetInputPortRealSignalPtrs(S,0); > > InputRealPtrsType uPtrs1 = ssGetInputPortRealSignalPtrs(S,1); > > > > real_T *y0 = ssGetOutputPortRealSignal(S,0); > > real_T *y1 = ssGetOutputPortRealSignal(S,1); > > > > /* Write data to the server */ > > vlineal= double(*uPtrs0[0]); > > vangular= double(*uPtrs1[0]); > > playerc_position2d_set_cmd_vel(position2d, vlineal, 0, > vangular, 1); > > > > /* Read data from the server */ > > playerc_client_read(client); > > *y0 =(position2d->vx);/* linear speed*/ > > *y1 =(position2d->va);/* angular speed */ > > } > > > > Perhaps somebody can understand where is the problem: > > I send goals of linear and angular speed; and the robot moves different” > > > > Thanks in advance. > > Marcelo Salazar > > > > > > > > > > > > Hello: > > > > I need to make a controller for the “P3-DX robot” but I don't understand > the behavior of the robot. > > > > I'm sending different goals of linear and angular speed, but the robot > give me a different data of speed. > > When I try the controller with Stage, it's works well. > > > > For example: V=[linear speed] ; O=[angular speed] > > > > I send I receive Obs. > > ----------------------------------------------------------------- > > V=0.1 V=0.1 That's right, no problem > > O=0.0 O=0.0 That's right, no problem > > ------------------------------------------------------------------ > > V=0.1 V=0.09 (aprox) This speed fall 10% aprox. > What's happen here? > > O=0.1 O=0.055 (aprox) This speed fall 50% aprox. > What's happen here? > > ------------------------------------------------------------------ > > V=0.0 V=0.0 (aprox) That's right, no problem > > O=0.1 O=0.0 (aprox) What's happen here? > > ------------------------------------------------------------------ > > > > I attach an image to explain the problem. > > Red: linear speed goal, > > Blue: linear speed read, > > Green: angular speed goal, > > Black: angular speed read. > > > > I don't understand what is the problem. > > Somebody know any problem with P3-DX and position2d? > > > > a greeting, > > Marcelo Salazar > > > > > ------------------------------------------------------------------------ > > ------------------------------------------------------------------------- > SF.Net email is sponsored by: The Future of Linux Business White Paper > from Novell. From the desktop to the data center, Linux is going > mainstream. Let it simplify your IT future. > http://altfarm.mediaplex.com/ad/ck/8857-50307-18918-4 > > > ------------------------------------------------------------------------ > > _______________________________________________ > Playerstage-users mailing list > Playerstage-users@... > https://lists.sourceforge.net/lists/listinfo/playerstage-users ```